404 results on '"Lodish HF"'
Search Results
2. Translation of vesicular stomatitis messenger RNA by extracts from mammalian and plant cells
- Author
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Stampfer, MR, Morrison, T, Baltimore, D, and Lodish, HF
- Published
- 1974
3. Both megakaryocytopoiesis and erythropoiesis are induced in mice infected with a retrovirus expressing an oncogenic erythropoietin receptor [see comments]
- Author
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Longmore, GD, primary, Pharr, P, additional, Neumann, D, additional, and Lodish, HF, additional
- Published
- 1993
- Full Text
- View/download PDF
4. Structure, function, and activation of the erythropoietin receptor
- Author
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Youssoufian, H, primary, Longmore, G, additional, Neumann, D, additional, Yoshimura, A, additional, and Lodish, HF, additional
- Published
- 1993
- Full Text
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5. Inhibition of receptor binding and neutralization of bioactivity by anti-erythropoietin monoclonal antibodies
- Author
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D'Andrea, AD, primary, Szklut, PJ, additional, Lodish, HF, additional, and Alderman, EM, additional
- Published
- 1990
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6. Differential binding of erythroid and myeloid progenitors to fibroblasts and fibronectin
- Author
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Tsai, S, Patel, V, Beaumont, E, Lodish, HF, Nathan, DG, and Sieff, CA
- Abstract
Using a novel coverslip-transfer culture technique, we recently demonstrated that primitive erythroid burst-forming units (BFU-E) can migrate, proliferate, and differentiate in intimate association with stromal fibroblastoid cells in the presence of serum proteins and erythropoietin. No other exogenous hemopoietic growth factors are required. Most of the colonies that develop in this system are very large erythroid bursts, and very few granulocyte-macrophage (GM) colonies are observed. In this report, we present data indicating that the predominance of erythroid burst colonies in this culture system is due to preferential binding of primitive erythroid progenitors to the stromal fibroblastoid cells and not to differential stimulation of these erythroid progenitors by these cells. We next show that the binding of BFU-E to stromal cells is blocked by anti-fibronectin antibodies. Finally, we demonstrate the preferential binding of BFU-E to fibronectin by using glass coverslips or Petri dishes coated with purified human plasma fibronectin. The binding is blocked by a monoclonal antibody specific for the cell-binding domain of fibronectin. We conclude that: primitive erythroid progenitors bind strongly whereas G and/or M progenitors (CFU-G/M) bind only weakly to fibronectin; primitive erythroid progenitors bind to the cell-binding domain on the fibronectin molecule; and erythroid progenitors and precursors remain bound to fibronectin throughout differentiation.
- Published
- 1987
- Full Text
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7. An adipose lncRAP2-Igf2bp2 complex enhances adipogenesis and energy expenditure by stabilizing target mRNAs.
- Author
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Alvarez-Dominguez JR, Winther S, Hansen JB, Lodish HF, and Knoll M
- Abstract
lncRAP2 is a conserved cytoplasmic lncRNA enriched in adipose tissue and required for adipogenesis. Using purification and in vivo interactome analyses, we show that lncRAP2 forms complexes with proteins that stabilize mRNAs and modulate translation, among them Igf2bp2. Surveying transcriptome-wide Igf2bp2 client mRNAs in white adipocytes reveals selective binding to mRNAs encoding adipogenic regulators and energy expenditure effectors, including adiponectin. These same target proteins are downregulated when either Igf2bp2 or lncRAP2 is downregulated, hindering adipocyte lipolysis. Proteomics and ribosome profiling show this occurs predominantly through mRNA accumulation, as lncRAP2-Igf2bp2 complex binding does not impact translation efficiency. Phenome-wide association studies reveal specific associations of genetic variants within both lncRAP2 and Igf2bp2 with body mass and type 2 diabetes, and both lncRAP2 and Igf2bp2 are suppressed in adipose depots of obese and diabetic individuals. Thus, the lncRAP2-Igf2bp2 complex potentiates adipose development and energy expenditure and is associated with susceptibility to obesity-linked diabetes., Competing Interests: The authors declare no competing interests., (© 2021 The Author(s).)
- Published
- 2021
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8. Engineered red blood cells carrying PCSK9 inhibitors persistently lower LDL and prevent obesity.
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Deshycka R, Sudaryo V, Huang NJ, Xie Y, Smeding LY, Choi MK, Ploegh HL, Lodish HF, and Pishesha N
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- Animals, Body Weight, Cells, Cultured, Diet, High-Fat adverse effects, Erythrocytes metabolism, Female, Genetic Engineering, Glycophorins chemistry, HEK293 Cells, Humans, Hyperlipidemias chemically induced, Hyperlipidemias metabolism, Mice, Pregnancy, Receptors, LDL chemistry, Recombinant Fusion Proteins genetics, Recombinant Fusion Proteins metabolism, Stem Cell Transplantation, Transduction, Genetic, Cholesterol, LDL blood, Down-Regulation, Glycophorins genetics, Hyperlipidemias prevention & control, Proprotein Convertase 9 blood, Receptors, LDL genetics
- Abstract
Low plasma levels of Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) are associated with decreased low-density lipoprotein (LDL) cholesterol and a reduced risk of cardiovascular disease. PCSK9 binds to the epidermal growth factor-like repeat A (EGFA) domain of LDL receptors (LDLR), very low-density lipoprotein receptors (VLDLR), apolipoprotein E receptor 2 (ApoER2), and lipoprotein receptor-related protein 1 (LRP1) and accelerates their degradation, thus acting as a key regulator of lipid metabolism. Antibody and RNAi-based PCSK9 inhibitor treatments lower cholesterol and prevent cardiovascular incidents in patients, but their high-cost hampers market penetration. We sought to develop a safe, long-term and one-time solution to treat hyperlipidemia. We created a cDNA encoding a chimeric protein in which the extracellular N- terminus of red blood cells (RBCs) specific glycophorin A was fused to the LDLR EGFA domain and introduced this gene into mouse bone marrow hematopoietic stem and progenitor cells (HSPCs). Following transplantation into irradiated mice, the animals produced RBCs with the EGFA domain (EGFA-GPA RBCs) displayed on their surface. These animals showed significantly reduced plasma PCSK9 (66.5% decrease) and reduced LDL levels (40% decrease) for as long as 12 months post-transplantation. Furthermore, the EGFA- GPA mice remained lean for life and maintained normal body weight under a high-fat diet. Hematopoietic stem cell gene therapy can generate red blood cells expressing an EGFA-glycophorin A chimeric protein as a practical and long-term strategy for treating chronic hyperlipidemia and obesity., Competing Interests: H.F.L. and H.L.P. served as scientific advisors and have/had equity in Rubius, a biotechnology company that seeks to exploit engineered red blood cells as therapeutics but does not provide financial support for the technology described in this paper. This does not alter our adherence to PLOS ONE policies on sharing data and materials.
- Published
- 2021
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9. Over 60 Years of Experimental Hematology (without a License).
- Author
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Lodish HF
- Subjects
- Cloning, Molecular, Erythrocytes metabolism, Erythrocytes pathology, Erythroid Precursor Cells cytology, Erythropoiesis genetics, Gene Expression, History, 20th Century, History, 21st Century, Humans, Receptors, Erythropoietin genetics, Receptors, Erythropoietin metabolism, Recombinant Proteins genetics, Recombinant Proteins metabolism, alpha-Globins genetics, alpha-Globins metabolism, beta-Globins genetics, beta-Globins metabolism, beta-Thalassemia metabolism, beta-Thalassemia pathology, Erythroid Precursor Cells metabolism, Hematology history, Molecular Biology history, Receptors, Erythropoietin history, beta-Thalassemia genetics
- Abstract
I am deeply honored to receive the International Society for Experimental Hematology (ISEH) 2020 Donald Metcalf Lecture Award. Although I am not a physician and have had no formal training in hematology, I have had the privilege of working with some of the top hematologists in the world, beginning in 1970 when Dr. David Nathan was a sabbatical visitor in my laboratory and introduced me to hematological diseases. And I take this award to be given not just to me but to an exceptional group of MD and PhD trainees and visitors in my laboratory who have cloned and characterized many proteins and RNAs important for red cell development and function. Many of these projects involved taking exceptionally large risks in developing and employing novel experimental technologies. Unsurprisingly, all of these trainees have gone on to become leaders in hematology and, more broadly, in molecular cell biology and molecular medicine. To illustrate some of the challenges we have faced and the technologies we had to develop, I have chosen several of our multiyear projects to describe in some detail: elucidating the regulation of translation of α- and β-globin mRNAs and the defect in beta thalassemia in the 1970s; cloning the Epo receptor and several red cell membrane proteins in the 1980s and 1990s; and more recently, determining the function of many microRNAs and long noncoding RNAs in red cell development. I summarize how we are currently utilizing single-cell transcriptomics (scRNAseq) to understand how dividing transit-amplifying burst-forming unit erythroid progenitors balance the need for more progenitor cells with the need for terminally differentiated erythroid cells, and to identify drugs potentially useful in treating Epo-resistant anemias such as Diamond Blackfan anemia. I hope that the lessons I learned in managing these diverse fellows and projects, initially without having grants to support them, will be helpful to others who would like to undertake ambitious and important lines of research in hematology., (Copyright © 2020 ISEH -- Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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10. Phosphocholine accumulation and PHOSPHO1 depletion promote adipose tissue thermogenesis.
- Author
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Jiang M, Chavarria TE, Yuan B, Lodish HF, and Huang NJ
- Subjects
- Adipocytes, Brown enzymology, Adipocytes, Brown metabolism, Adipose Tissue, Brown enzymology, Animals, Cold Temperature, Mice, Mice, Inbred C57BL, Mice, Knockout, Phosphoric Monoester Hydrolases deficiency, Adipose Tissue, Brown physiology, Phosphoric Monoester Hydrolases genetics, Phosphorylcholine metabolism, Thermogenesis
- Abstract
Phosphocholine phosphatase-1 (PHOSPHO1) is a phosphocholine phosphatase that catalyzes the hydrolysis of phosphocholine (PC) to choline. Here we demonstrate that the PHOSPHO1 transcript is highly enriched in mature brown adipose tissue (BAT) and is further induced by cold and isoproterenol treatments of BAT and primary brown adipocytes. In defining the functional relevance of PHOPSPHO1 in BAT thermogenesis and energy metabolism, we show that PHOSPHO1 knockout mice are cold-tolerant, with higher expression of thermogenic genes in BAT, and are protected from high-fat diet-induced obesity and development of insulin resistance. Treatment of mice with the PHOSPHO1 substrate phosphocholine is sufficient to induce cold tolerance, thermogenic gene expression, and allied metabolic benefits. Our results reveal a role of PHOSPHO1 as a negative regulator of BAT thermogenesis, and inhibition of PHOSPHO1 or enhancement of phosphocholine represent innovative approaches to manage the metabolic syndrome., Competing Interests: The authors declare no competing interest.
- Published
- 2020
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11. Rate of Progression through a Continuum of Transit-Amplifying Progenitor Cell States Regulates Blood Cell Production.
- Author
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Li H, Natarajan A, Ezike J, Barrasa MI, Le Y, Feder ZA, Yang H, Ma C, Markoulaki S, and Lodish HF
- Subjects
- Animals, Blood Cells cytology, Cell Differentiation genetics, Cell Division genetics, Cells, Cultured, Erythrocytes cytology, Erythrocytes metabolism, Erythroid Cells cytology, Erythroid Cells metabolism, Erythroid Precursor Cells cytology, Erythropoiesis genetics, Glucocorticoids genetics, High-Throughput Nucleotide Sequencing methods, Mice, Single-Cell Analysis methods, Transcriptome genetics, Blood Cells metabolism, Cell Proliferation genetics, Erythroid Precursor Cells metabolism, Hematopoiesis genetics
- Abstract
The nature of cell-state transitions during the transit-amplifying phases of many developmental processes-hematopoiesis in particular-is unclear. Here, we use single-cell RNA sequencing to demonstrate a continuum of transcriptomic states in committed transit-amplifying erythropoietic progenitors, which correlates with a continuum of proliferative potentials in these cells. We show that glucocorticoids enhance erythrocyte production by slowing the rate of progression through this developmental continuum of transit-amplifying progenitors, permitting more cell divisions prior to terminal erythroid differentiation. Mechanistically, glucocorticoids prolong expression of genes that antagonize and slow induction of genes that drive terminal erythroid differentiation. Erythroid progenitor daughter cell pairs have similar transcriptomes with or without glucocorticoid stimulation, indicating largely symmetric cell division. Thus, the rate of progression along a developmental continuum dictates the absolute number of erythroid cells generated from each transit-amplifying progenitor, suggesting a paradigm for regulating the total output of differentiated cells in numerous other developmental processes., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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12. FAM210B is an erythropoietin target and regulates erythroid heme synthesis by controlling mitochondrial iron import and ferrochelatase activity.
- Author
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Yien YY, Shi J, Chen C, Cheung JTM, Grillo AS, Shrestha R, Li L, Zhang X, Kafina MD, Kingsley PD, King MJ, Ablain J, Li H, Zon LI, Palis J, Burke MD, Bauer DE, Orkin SH, Koehler CM, Phillips JD, Kaplan J, Ward DM, Lodish HF, and Paw BH
- Subjects
- Animals, Erythroid Cells cytology, Erythropoiesis, HEK293 Cells, Humans, Membrane Proteins chemistry, Mice, Mitochondrial Membranes metabolism, Mitochondrial Proteins chemistry, Protein Transport, Erythroid Cells metabolism, Erythropoietin metabolism, Ferrochelatase metabolism, Heme biosynthesis, Iron metabolism, Membrane Proteins metabolism, Mitochondria metabolism, Mitochondrial Proteins metabolism
- Abstract
Erythropoietin (EPO) signaling is critical to many processes essential to terminal erythropoiesis. Despite the centrality of iron metabolism to erythropoiesis, the mechanisms by which EPO regulates iron status are not well-understood. To this end, here we profiled gene expression in EPO-treated 32D pro-B cells and developing fetal liver erythroid cells to identify additional iron regulatory genes. We determined that FAM210B, a mitochondrial inner-membrane protein, is essential for hemoglobinization, proliferation, and enucleation during terminal erythroid maturation. Fam210b deficiency led to defects in mitochondrial iron uptake, heme synthesis, and iron-sulfur cluster formation. These defects were corrected with a lipid-soluble, small-molecule iron transporter, hinokitiol, in Fam210b -deficient murine erythroid cells and zebrafish morphants. Genetic complementation experiments revealed that FAM210B is not a mitochondrial iron transporter but is required for adequate mitochondrial iron import to sustain heme synthesis and iron-sulfur cluster formation during erythroid differentiation. FAM210B was also required for maximal ferrochelatase activity in differentiating erythroid cells. We propose that FAM210B functions as an adaptor protein that facilitates the formation of an oligomeric mitochondrial iron transport complex, required for the increase in iron acquisition for heme synthesis during terminal erythropoiesis. Collectively, our results reveal a critical mechanism by which EPO signaling regulates terminal erythropoiesis and iron metabolism., (© 2018 Yien et al.)
- Published
- 2018
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13. SYK kinase mediates brown fat differentiation and activation.
- Author
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Knoll M, Winther S, Natarajan A, Yang H, Jiang M, Thiru P, Shahsafaei A, Chavarria TE, Lamming DW, Sun L, Hansen JB, and Lodish HF
- Subjects
- Adipocytes, Brown cytology, Animals, Cell Proliferation, Cells, Cultured, Humans, Male, Mice, Inbred C57BL, Mice, Knockout, Syk Kinase genetics, Uncoupling Protein 1 genetics, Uncoupling Protein 1 metabolism, Adipocytes, Brown enzymology, Adipose Tissue, Brown metabolism, Cell Differentiation, Syk Kinase metabolism
- Abstract
Brown adipose tissue (BAT) metabolism influences glucose homeostasis and metabolic health in mice and humans. Sympathetic stimulation of β-adrenergic receptors in response to cold induces proliferation, differentiation, and UCP1 expression in pre-adipocytes and mature brown adipocytes. Here we show that spleen tyrosine kinase (SYK) is upregulated during brown adipocyte differentiation and activated by β-adrenergic stimulation. Deletion or inhibition of SYK, a kinase known for its essential roles in the immune system, blocks brown and white pre-adipocyte proliferation and differentiation in vitro, and results in diminished expression of Ucp1 and other genes regulating brown adipocyte function in response to β-adrenergic stimulation. Adipocyte-specific SYK deletion in mice reduces BAT mass and BAT that developed consisted of SYK-expressing brown adipocytes that had escaped homozygous Syk deletion. SYK inhibition in vivo represses β-agonist-induced thermogenesis and oxygen consumption. These results establish SYK as an essential mediator of brown fat formation and function.
- Published
- 2017
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14. Emerging mechanisms of long noncoding RNA function during normal and malignant hematopoiesis.
- Author
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Alvarez-Dominguez JR and Lodish HF
- Subjects
- Animals, Embryonic Development genetics, Humans, Models, Biological, Proteins metabolism, RNA, Long Noncoding metabolism, Hematologic Neoplasms genetics, Hematopoiesis genetics, RNA, Long Noncoding genetics
- Abstract
Long noncoding RNAs (lncRNAs) are increasingly recognized as vital components of gene programs controlling cell differentiation and function. Central to their functions is an ability to act as scaffolds or as decoys that recruit or sequester effector proteins from their DNA, RNA, or protein targets. lncRNA-modulated effectors include regulators of transcription, chromatin organization, RNA processing, and translation, such that lncRNAs can influence gene expression at multiple levels. Here we review the current understanding of how lncRNAs help coordinate gene expression to modulate cell fate in the hematopoietic system. We focus on a growing number of mechanistic studies to synthesize emerging principles of lncRNA function, emphasizing how they facilitate diversification of gene programming during development. We also survey how disrupted lncRNA function can contribute to malignant transformation, highlighting opportunities for therapeutic intervention in specific myeloid and lymphoid cancers. Finally, we discuss challenges and prospects for further elucidation of lncRNA mechanisms., (© 2017 by The American Society of Hematology.)
- Published
- 2017
- Full Text
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15. Fifty years of mentoring and advising.
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Lodish HF
- Subjects
- Humans, Laboratories, Mentors, Research Personnel, Mentoring trends, Personnel Selection methods
- Abstract
Advancement of science depends on thoughtfully mentoring a rare group of scientists that are highly educated, creative, and motivated-and that come from every country in the world. On the basis of my own experiences, I suggest ways to recruit top young scientists of both genders, support their development into leading researchers, and advise them about careers inside and outside of academia. Creating a family-friendly environment within the laboratory and the institution is crucial to these efforts., (© 2017 Lodish. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).)
- Published
- 2017
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16. Thyroid hormone receptor beta and NCOA4 regulate terminal erythrocyte differentiation.
- Author
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Gao X, Lee HY, Li W, Platt RJ, Barrasa MI, Ma Q, Elmes RR, Rosenfeld MG, and Lodish HF
- Subjects
- Animals, Chromatin genetics, Chromatin metabolism, Genome-Wide Association Study, Humans, Mice, Mice, Knockout, Nuclear Receptor Coactivators genetics, Thyroid Hormone Receptors beta genetics, Thyroid Hormones genetics, Cell Differentiation, Nuclear Receptor Coactivators metabolism, Reticulocytes metabolism, Thyroid Hormone Receptors beta metabolism, Thyroid Hormones metabolism
- Abstract
An effect of thyroid hormone (TH) on erythropoiesis has been known for more than a century but the molecular mechanism(s) by which TH affects red cell formation is still elusive. Here we demonstrate an essential role of TH during terminal human erythroid cell differentiation; specific depletion of TH from the culture medium completely blocked terminal erythroid differentiation and enucleation. Treatment with TRβ agonists stimulated premature erythroblast differentiation in vivo and alleviated anemic symptoms in a chronic anemia mouse model by regulating erythroid gene expression. To identify factors that cooperate with TRβ during human erythroid terminal differentiation, we conducted RNA-seq in human reticulocytes and identified nuclear receptor coactivator 4 (NCOA4) as a critical regulator of terminal differentiation. Furthermore, Ncoa4
-/- mice are anemic in perinatal periods and fail to respond to TH by enhanced erythropoiesis. Genome-wide analysis suggests that TH promotes NCOA4 recruitment to chromatin regions that are in proximity to Pol II and are highly associated with transcripts abundant during terminal differentiation. Collectively, our results reveal the molecular mechanism by which TH functions during red blood cell formation, results that are potentially useful to treat certain anemias., Competing Interests: The authors declare no conflict of interest.- Published
- 2017
- Full Text
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17. Genetically engineered red cells expressing single domain camelid antibodies confer long-term protection against botulinum neurotoxin.
- Author
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Huang NJ, Pishesha N, Mukherjee J, Zhang S, Deshycka R, Sudaryo V, Dong M, Shoemaker CB, and Lodish HF
- Subjects
- Animals, Antibodies, Neutralizing administration & dosage, Antibodies, Neutralizing genetics, Antibodies, Neutralizing metabolism, Botulinum Toxins, Type A metabolism, Botulism etiology, Botulism therapy, Erythrocyte Transfusion, Erythrocytes virology, Erythroid Precursor Cells metabolism, Erythroid Precursor Cells transplantation, Erythroid Precursor Cells virology, Genetic Vectors genetics, Genetic Vectors metabolism, Glycophorins genetics, Glycophorins metabolism, Humans, Membrane Glycoproteins genetics, Membrane Glycoproteins metabolism, Metalloendopeptidases genetics, Metalloendopeptidases metabolism, Mice, Mice, Inbred C57BL, Retroviridae genetics, Retroviridae metabolism, Single-Domain Antibodies administration & dosage, Single-Domain Antibodies metabolism, Botulinum Toxins, Type A toxicity, Erythrocytes metabolism, Genetic Engineering, Single-Domain Antibodies genetics
- Abstract
A short half-life in the circulation limits the application of therapeutics such as single-domain antibodies (VHHs). We utilize red blood cells to prolong the circulatory half-life of VHHs. Here we present VHHs against botulinum neurotoxin A (BoNT/A) on the surface of red blood cells by expressing chimeric proteins of VHHs with Glycophorin A or Kell. Mice whose red blood cells carry the chimeric proteins exhibit resistance to 10,000 times the lethal dose (LD
50 ) of BoNT/A, and transfusion of these red blood cells into naive mice affords protection for up to 28 days. We further utilize an improved CD34+ culture system to engineer human red blood cells that express these chimeric proteins. Mice transfused with these red blood cells are resistant to highly lethal doses of BoNT/A. We demonstrate that engineered red blood cells expressing VHHs can provide prolonged prophylactic protection against bacterial toxins without inducing inhibitory immune responses and illustrates the potentially broad translatability of our strategy for therapeutic applications.The therapeutic use of single-chain antibodies (VHHs) is limited by their short half-life in the circulation. Here the authors engineer mouse and human red blood cells to express VHHs against botulinum neurotoxin A (BoNT/A) on their surface and show that an infusion of these cells into mice confers long lasting protection against a high dose of BoNT/A.- Published
- 2017
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18. The Super-Enhancer-Derived alncRNA-EC7/Bloodlinc Potentiates Red Blood Cell Development in trans.
- Author
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Alvarez-Dominguez JR, Knoll M, Gromatzky AA, and Lodish HF
- Subjects
- Animals, Cells, Cultured, Enhancer Elements, Genetic, Erythroid Cells metabolism, Gene Expression Regulation, Humans, Mice, Transcription, Genetic, Erythrocytes physiology, Erythropoiesis, RNA, Long Noncoding physiology
- Abstract
Enhancer-derived RNAs are thought to act locally by contributing to their parent enhancer function. Whether large domains of clustered enhancers (super-enhancers) also produce cis-acting RNAs, however, remains unclear. Unlike typical enhancers, super-enhancers form large spans of robustly transcribed chromatin, amassing capped and polyadenylated RNAs that are sufficiently abundant to sustain trans functions. Here, we show that one such RNA, alncRNA-EC7/Bloodlinc, is transcribed from a super-enhancer of the erythroid membrane transporter SLC4A1/BAND3 but diffuses beyond this site. Bloodlinc localizes to trans-chromosomal loci encoding critical regulators and effectors of terminal erythropoiesis and directly binds chromatin-organizing and transcription factors, including the chromatin attachment factor HNRNPU. Inhibiting Bloodlinc or Hnrnpu compromises the terminal erythropoiesis gene program, blocking red cell production, whereas expressing Bloodlinc ectopically stimulates this program and can promote erythroblast proliferation and enucleation in the absence of differentiation stimuli. Thus, Bloodlinc is a trans-acting super-enhancer RNA that potentiates red blood cell development., (Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
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19. Erythropoietin signaling regulates heme biosynthesis.
- Author
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Chung J, Wittig JG, Ghamari A, Maeda M, Dailey TA, Bergonia H, Kafina MD, Coughlin EE, Minogue CE, Hebert AS, Li L, Kaplan J, Lodish HF, Bauer DE, Orkin SH, Cantor AB, Maeda T, Phillips JD, Coon JJ, Pagliarini DJ, Dailey HA, and Paw BH
- Subjects
- Animals, Cyclic AMP-Dependent Protein Kinases metabolism, Humans, Mice, Mitochondrial Membranes metabolism, Zebrafish, A Kinase Anchor Proteins metabolism, Erythropoietin metabolism, GATA1 Transcription Factor metabolism, Heme biosynthesis, Signal Transduction
- Abstract
Heme is required for survival of all cells, and in most eukaryotes, is produced through a series of eight enzymatic reactions. Although heme production is critical for many cellular processes, how it is coupled to cellular differentiation is unknown. Here, using zebrafish, murine, and human models, we show that erythropoietin (EPO) signaling, together with the GATA1 transcriptional target, AKAP10 , regulates heme biosynthesis during erythropoiesis at the outer mitochondrial membrane. This integrated pathway culminates with the direct phosphorylation of the crucial heme biosynthetic enzyme, ferrochelatase (FECH) by protein kinase A (PKA). Biochemical, pharmacological, and genetic inhibition of this signaling pathway result in a block in hemoglobin production and concomitant intracellular accumulation of protoporphyrin intermediates. Broadly, our results implicate aberrant PKA signaling in the pathogenesis of hematologic diseases. We propose a unifying model in which the erythroid transcriptional program works in concert with post-translational mechanisms to regulate heme metabolism during normal development.
- Published
- 2017
- Full Text
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20. Engineered erythrocytes covalently linked to antigenic peptides can protect against autoimmune disease.
- Author
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Pishesha N, Bilate AM, Wibowo MC, Huang NJ, Li Z, Deshycka R, Bousbaine D, Li H, Patterson HC, Dougan SK, Maruyama T, Lodish HF, and Ploegh HL
- Abstract
Current therapies for autoimmune diseases rely on traditional immunosuppressive medications that expose patients to an increased risk of opportunistic infections and other complications. Immunoregulatory interventions that act prophylactically or therapeutically to induce antigen-specific tolerance might overcome these obstacles. Here we use the transpeptidase sortase to covalently attach disease-associated autoantigens to genetically engineered and to unmodified red blood cells as a means of inducing antigen-specific tolerance. This approach blunts the contribution to immunity of major subsets of immune effector cells (B cells, CD4
+ and CD8+ T cells) in an antigen-specific manner. Transfusion of red blood cells expressing self-antigen epitopes can alleviate and even prevent signs of disease in experimental autoimmune encephalomyelitis, as well as maintain normoglycemia in a mouse model of type 1 diabetes.- Published
- 2017
- Full Text
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21. US immigration order strikes against biotech.
- Author
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Levin JM, Holtzman SH, Maraganore J, Hastings PJ, Cohen R, Dahiyat B, Adams J, Adams C, Ahrens B, Albers J, Aspinall MG, Audia JE, Babler M, Barrett P, Barry Z, Bermingham N, Bloch S, Blum RI, Bolno PB, Bonney MW, Booth B, Bradbury DM, Brauer SK, Byers B, Cagnoni PJ, Cali BM, Ciechanover I, Clark C, Clayman MD, Cleland JL, Cobb P, Cooper R, Currie MG, Diekman J, Dobmeier EL, Doerfler D, Donley EL, Dunsire D, During M, Eckstein JW, Elenko E, Exter NA, Fleming JJ, Flesher GJ, Formela JF, Forrester R, Francois C, Franklin H, Freeman MW, Furst H, Gage LP, Galakatos N, Gallagher BM, Geraghty JA, Gill S, Goeddel DV, Goldsmith MA, Gowen M, Goyal V, Graney T, Grayzel D, Greene B, Grint P, Gutierrez-Ramos JC, Haney B, Ha-Ngoc T, Harris T, Hasnain F, Hata YS, Hecht P, Henshaw L, Heyman R, Hoppenot H, Horvitz HR, Hughes TE, Hutton WS, Isaacs ST, Jenkins A, Jonker J, Kaplan J, Karsen P, Keiper J, Kim J, Kindler J, King R, King V, Kjellson N, Koenig S, Koenig G, Kolchinsky P, Laikind P, Langer RB, Lee JJ, Leff JS, Leicher BA, Leschly N, Levin A, Levin M, Levine AJ, Levy A, Liu DR, Lodish HF, Lopatin U, Love TW, Macdonald G, Maderis GJ, Mahadevia A, Mahanthappa NK, Martin JF, Martin A, Martucci WE, McArthur JG, McCann CM, McCarthy SA, McDonough CG, Mendlein J, Miller L, Miralles D, Moch KI, More B, Myers AG, Narachi MA, Nashat A, Nelson W, Newell WJ, Olle B, Osborn JE, Owens JC, Pande A, Papadopoulos S, Parker HS, Parmar KM, Patterson MR, Paul SM, Perez R, Perry M, Pfeffer CG, Powell M, Pruzanski M, Purcell DJ, Rakhit A, Ramamoorthi K, Rastetter W, Rawcliffe AA, Reid LE, Renaud RC, Rhodes JP, Rieflin WJ, Robins C, Rocklage SM, Rosenblatt M, Rosin JG, Rutter WJ, Saha S, Samuels C, Sato VL, Scangos G, Scarlett JA, Schenkein D, Schreiber SL, Schwab A, Sekhri P, Shah R, Shenk T, Siegall CB, Simon NJ, Simonian N, Stein J, Su M, Szela MT, Taglietti M, Tandon N, Termeer H, Thornberry NA, Tolar M, Ulevitch R, Vaishnaw AK, VanLent A, Varsavsky M, Vlasuk GP, Vounatsos M, Waksal SG, Warma N, Watts RJ, Werber Y, Westphal C, Wierenga W, Williams DE, Williams LR, Xanthopoulos KG, Zohar D, and Zweifach SS
- Subjects
- Humans, Population Dynamics, Biotechnology legislation & jurisprudence, Emigration and Immigration legislation & jurisprudence, Public Policy legislation & jurisprudence
- Published
- 2017
- Full Text
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22. TGF-β inhibitors stimulate red blood cell production by enhancing self-renewal of BFU-E erythroid progenitors.
- Author
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Gao X, Lee HY, da Rocha EL, Zhang C, Lu YF, Li D, Feng Y, Ezike J, Elmes RR, Barrasa MI, Cahan P, Li H, Daley GQ, and Lodish HF
- Subjects
- Anemia metabolism, Anemia therapy, Animals, Erythrocytes cytology, Erythroid Precursor Cells cytology, Erythropoietin metabolism, Humans, Mice, Antigens, Differentiation metabolism, Erythrocytes metabolism, Erythroid Precursor Cells metabolism, Proteoglycans metabolism, Receptors, Transforming Growth Factor beta metabolism, Signal Transduction physiology, Transforming Growth Factor beta metabolism
- Abstract
Burst-forming unit erythroid progenitors (BFU-Es) are so named based on their ability to generate in methylcellulose culture large colonies of erythroid cells that consist of "bursts" of smaller erythroid colonies derived from the later colony-forming unit erythroid progenitor erythropoietin (Epo)-dependent progenitors. "Early" BFU-E cells forming large BFU-E colonies presumably have higher capacities for self-renewal than do "late" BFU-Es forming small colonies, but the mechanism underlying this heterogeneity remains unknown. We show that the type III transforming growth factor β (TGF-β) receptor (TβRIII) is a marker that distinguishes early and late BFU-Es. Transient elevation of TβRIII expression promotes TGF-β signaling during the early BFU-E to late BFU-E transition. Blocking TGF-β signaling using a receptor kinase inhibitor increases early BFU-E cell self-renewal and total erythroblast production, suggesting the usefulness of this type of drug in treating Epo-unresponsive anemias., (© 2016 by The American Society of Hematology.)
- Published
- 2016
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23. A Long Noncoding RNA lincRNA-EPS Acts as a Transcriptional Brake to Restrain Inflammation.
- Author
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Atianand MK, Hu W, Satpathy AT, Shen Y, Ricci EP, Alvarez-Dominguez JR, Bhatta A, Schattgen SA, McGowan JD, Blin J, Braun JE, Gandhi P, Moore MJ, Chang HY, Lodish HF, Caffrey DR, and Fitzgerald KA
- Subjects
- Animals, Chromatids metabolism, Gene Deletion, Humans, Listeria monocytogenes physiology, Listeriosis immunology, Macrophages metabolism, Macrophages microbiology, Macrophages virology, Mice, Mice, Inbred C57BL, RNA, Long Noncoding genetics, Respirovirus Infections immunology, Sendai virus physiology, Toll-Like Receptors metabolism, Transcriptome, Gene Expression Regulation, Inflammation genetics, Macrophages immunology, RNA, Long Noncoding metabolism
- Abstract
Long intergenic noncoding RNAs (lincRNAs) are important regulators of gene expression. Although lincRNAs are expressed in immune cells, their functions in immunity are largely unexplored. Here, we identify an immunoregulatory lincRNA, lincRNA-EPS, that is precisely regulated in macrophages to control the expression of immune response genes (IRGs). Transcriptome analysis of macrophages from lincRNA-EPS-deficient mice, combined with gain-of-function and rescue experiments, revealed a specific role for this lincRNA in restraining IRG expression. Consistently, lincRNA-EPS-deficient mice manifest enhanced inflammation and lethality following endotoxin challenge in vivo. lincRNA-EPS localizes at regulatory regions of IRGs to control nucleosome positioning and repress transcription. Further, lincRNA-EPS mediates these effects by interacting with heterogeneous nuclear ribonucleoprotein L via a CANACA motif located in its 3' end. Together, these findings identify lincRNA-EPS as a repressor of inflammatory responses, highlighting the importance of lincRNAs in the immune system., Competing Interests: CONFLICT OF INTERESTS The authors do not have any conflict of interests to declare., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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24. Efficient CRISPR-Cas9 mediated gene disruption in primary erythroid progenitor cells.
- Author
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Li H, Shi J, Huang NJ, Pishesha N, Natarajan A, Eng JC, and Lodish HF
- Subjects
- Erythroid Precursor Cells cytology, Humans, CRISPR-Cas Systems, Erythroid Precursor Cells metabolism, Gene Deletion
- Published
- 2016
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25. A respiratory chain controlled signal transduction cascade in the mitochondrial intermembrane space mediates hydrogen peroxide signaling.
- Author
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Patterson HC, Gerbeth C, Thiru P, Vögtle NF, Knoll M, Shahsafaei A, Samocha KE, Huang CX, Harden MM, Song R, Chen C, Kao J, Shi J, Salmon W, Shaul YD, Stokes MP, Silva JC, Bell GW, MacArthur DG, Ruland J, Meisinger C, and Lodish HF
- Subjects
- Animals, Cells, Cultured, Chickens, Enzyme Activation, Intracellular Signaling Peptides and Proteins metabolism, Mice, Phosphorylation, Protein-Tyrosine Kinases metabolism, Reactive Oxygen Species metabolism, Syk Kinase, Tyrosine metabolism, Electron Transport, Hydrogen Peroxide metabolism, Mitochondrial Membranes metabolism, Signal Transduction
- Abstract
Reactive oxygen species (ROS) such as hydrogen peroxide (H2O2) govern cellular homeostasis by inducing signaling. H2O2 modulates the activity of phosphatases and many other signaling molecules through oxidation of critical cysteine residues, which led to the notion that initiation of ROS signaling is broad and nonspecific, and thus fundamentally distinct from other signaling pathways. Here, we report that H2O2 signaling bears hallmarks of a regular signal transduction cascade. It is controlled by hierarchical signaling events resulting in a focused response as the results place the mitochondrial respiratory chain upstream of tyrosine-protein kinase Lyn, Lyn upstream of tyrosine-protein kinase SYK (Syk), and Syk upstream of numerous targets involved in signaling, transcription, translation, metabolism, and cell cycle regulation. The active mediators of H2O2 signaling colocalize as H2O2 induces mitochondria-associated Lyn and Syk phosphorylation, and a pool of Lyn and Syk reside in the mitochondrial intermembrane space. Finally, the same intermediaries control the signaling response in tissues and species responsive to H2O2 as the respiratory chain, Lyn, and Syk were similarly required for H2O2 signaling in mouse B cells, fibroblasts, and chicken DT40 B cells. Consistent with a broad role, the Syk pathway is coexpressed across tissues, is of early metazoan origin, and displays evidence of evolutionary constraint in the human. These results suggest that H2O2 signaling is under control of a signal transduction pathway that links the respiratory chain to the mitochondrial intermembrane space-localized, ubiquitous, and ancient Syk pathway in hematopoietic and nonhematopoietic cells.
- Published
- 2015
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26. PPAR-α and glucocorticoid receptor synergize to promote erythroid progenitor self-renewal.
- Author
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Lee HY, Gao X, Barrasa MI, Li H, Elmes RR, Peters LL, and Lodish HF
- Subjects
- Acute Disease, Anemia drug therapy, Anemia metabolism, Anemia pathology, Anemia, Hemolytic metabolism, Animals, Butyrates pharmacology, Butyrates therapeutic use, Cell Culture Techniques, Cells, Cultured, Chromatin genetics, Chromatin metabolism, Chronic Disease, Disease Models, Animal, Erythroid Precursor Cells drug effects, Erythroid Precursor Cells metabolism, Erythropoietin pharmacology, Female, Fenofibrate pharmacology, Glucocorticoids pharmacology, Humans, Liver cytology, Liver drug effects, Liver embryology, Mice, PPAR alpha agonists, PPAR alpha deficiency, Phenylhydrazines pharmacology, Phenylurea Compounds pharmacology, Phenylurea Compounds therapeutic use, Signal Transduction drug effects, Erythroid Precursor Cells cytology, Erythropoiesis drug effects, PPAR alpha metabolism, Receptors, Glucocorticoid metabolism
- Abstract
Many acute and chronic anaemias, including haemolysis, sepsis and genetic bone marrow failure diseases such as Diamond-Blackfan anaemia, are not treatable with erythropoietin (Epo), because the colony-forming unit erythroid progenitors (CFU-Es) that respond to Epo are either too few in number or are not sensitive enough to Epo to maintain sufficient red blood cell production. Treatment of these anaemias requires a drug that acts at an earlier stage of red cell formation and enhances the formation of Epo-sensitive CFU-E progenitors. Recently, we showed that glucocorticoids specifically stimulate self-renewal of an early erythroid progenitor, burst-forming unit erythroid (BFU-E), and increase the production of terminally differentiated erythroid cells. Here we show that activation of the peroxisome proliferator-activated receptor α (PPAR-α) by the PPAR-α agonists GW7647 and fenofibrate synergizes with the glucocorticoid receptor (GR) to promote BFU-E self-renewal. Over time these agonists greatly increase production of mature red blood cells in cultures of both mouse fetal liver BFU-Es and mobilized human adult CD34(+) peripheral blood progenitors, with a new and effective culture system being used for the human cells that generates normal enucleated reticulocytes. Although Ppara(-/-) mice show no haematological difference from wild-type mice in both normal and phenylhydrazine (PHZ)-induced stress erythropoiesis, PPAR-α agonists facilitate recovery of wild-type but not Ppara(-/-) mice from PHZ-induced acute haemolytic anaemia. We also show that PPAR-α alleviates anaemia in a mouse model of chronic anaemia. Finally, both in control and corticosteroid-treated BFU-E cells, PPAR-α co-occupies many chromatin sites with GR; when activated by PPAR-α agonists, additional PPAR-α is recruited to GR-adjacent sites and presumably facilitates GR-dependent BFU-E self-renewal. Our discovery of the role of PPAR-α agonists in stimulating self-renewal of early erythroid progenitor cells suggests that the clinically tested PPAR-α agonists we used may improve the efficacy of corticosteroids in treating Epo-resistant anaemias.
- Published
- 2015
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27. De Novo Reconstruction of Adipose Tissue Transcriptomes Reveals Long Non-coding RNA Regulators of Brown Adipocyte Development.
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Alvarez-Dominguez JR, Bai Z, Xu D, Yuan B, Lo KA, Yoon MJ, Lim YC, Knoll M, Slavov N, Chen S, Peng C, Lodish HF, and Sun L
- Subjects
- Adipocytes, Brown metabolism, Adipogenesis, Adipose Tissue, Brown cytology, Adipose Tissue, Brown metabolism, Adipose Tissue, White metabolism, Animals, Base Sequence, Cell Line, Cells, Cultured, Humans, Mice, Thermogenesis, Transcriptional Activation, Adipocytes, Brown cytology, RNA, Long Noncoding genetics, Transcriptome
- Abstract
Brown adipose tissue (BAT) protects against obesity by promoting energy expenditure via uncoupled respiration. To uncover BAT-specific long non-coding RNAs (lncRNAs), we used RNA-seq to reconstruct de novo transcriptomes of mouse brown, inguinal white, and epididymal white fat and identified ∼1,500 lncRNAs, including 127 BAT-restricted loci induced during differentiation and often targeted by key regulators PPARγ, C/EBPα, and C/EBPβ. One of them, lnc-BATE1, is required for establishment and maintenance of BAT identity and thermogenic capacity. lnc-BATE1 inhibition impairs concurrent activation of brown fat and repression of white fat genes and is partially rescued by exogenous lnc-BATE1 with mutated siRNA-targeting sites, demonstrating a function in trans. We show that lnc-BATE1 binds heterogeneous nuclear ribonucleoprotein U and that both are required for brown adipogenesis. Our work provides an annotated catalog for the study of fat depot-selective lncRNAs and establishes lnc-BATE1 as a regulator of BAT development and physiology., (Copyright © 2015 Elsevier Inc. All rights reserved.)
- Published
- 2015
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28. Genome-wide association study follow-up identifies cyclin A2 as a regulator of the transition through cytokinesis during terminal erythropoiesis.
- Author
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Ludwig LS, Cho H, Wakabayashi A, Eng JC, Ulirsch JC, Fleming MD, Lodish HF, and Sankaran VG
- Subjects
- Animals, Cell Differentiation, Cell Size, Cyclin A2 antagonists & inhibitors, Cyclin A2 metabolism, Erythroid Precursor Cells cytology, Follow-Up Studies, GATA1 Transcription Factor genetics, GATA1 Transcription Factor metabolism, Gene Expression Regulation, Developmental, Genetic Loci, Genome-Wide Association Study, Humans, Linkage Disequilibrium, Mice, Primary Cell Culture, RNA, Messenger antagonists & inhibitors, RNA, Messenger metabolism, RNA, Small Interfering genetics, RNA, Small Interfering metabolism, Signal Transduction, Cyclin A2 genetics, Cytokinesis genetics, Erythroid Precursor Cells metabolism, Erythropoiesis genetics, Genome, RNA, Messenger genetics
- Abstract
Genome-wide association studies (GWAS) hold tremendous promise to improve our understanding of human biology. Recent GWAS have revealed over 75 loci associated with erythroid traits, including the 4q27 locus that is associated with red blood cell size (mean corpuscular volume). The close linkage disequilibrium block at this locus harbors the CCNA2 gene that encodes cyclin A2. CCNA2 mRNA is highly expressed in human and murine erythroid progenitor cells and regulated by the essential erythroid transcription factor GATA1. To understand the role of cyclin A2 in erythropoiesis, we have reduced expression of this gene using short hairpin RNAs in a primary murine erythroid culture system. We demonstrate that cyclin A2 levels affect erythroid cell size by regulating the passage through cytokinesis during the final cell division of terminal erythropoiesis. Our study provides new insight into cell cycle regulation during terminal erythropoiesis and more generally illustrates the value of functional GWAS follow-up to gain mechanistic insight into hematopoiesis., (© 2015 Wiley Periodicals, Inc.)
- Published
- 2015
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29. TMEM14C is required for erythroid mitochondrial heme metabolism.
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Yien YY, Robledo RF, Schultz IJ, Takahashi-Makise N, Gwynn B, Bauer DE, Dass A, Yi G, Li L, Hildick-Smith GJ, Cooney JD, Pierce EL, Mohler K, Dailey TA, Miyata N, Kingsley PD, Garone C, Hattangadi SM, Huang H, Chen W, Keenan EM, Shah DI, Schlaeger TM, DiMauro S, Orkin SH, Cantor AB, Palis J, Koehler CM, Lodish HF, Kaplan J, Ward DM, Dailey HA, Phillips JD, Peters LL, and Paw BH
- Subjects
- Anemia metabolism, Animals, Cell Line, Erythroid Cells metabolism, Gene Expression Regulation, Hemoglobins metabolism, Liver embryology, Membrane Proteins genetics, Membrane Proteins metabolism, Mice, Mitochondrial Membrane Transport Proteins genetics, Mitochondrial Membranes metabolism, Porphyrins metabolism, Protoporphyrins metabolism, RNA, Small Interfering metabolism, Erythropoiesis genetics, Heme metabolism, Mitochondria metabolism, Mitochondrial Membrane Transport Proteins metabolism
- Abstract
The transport and intracellular trafficking of heme biosynthesis intermediates are crucial for hemoglobin production, which is a critical process in developing red cells. Here, we profiled gene expression in terminally differentiating murine fetal liver-derived erythroid cells to identify regulators of heme metabolism. We determined that TMEM14C, an inner mitochondrial membrane protein that is enriched in vertebrate hematopoietic tissues, is essential for erythropoiesis and heme synthesis in vivo and in cultured erythroid cells. In mice, TMEM14C deficiency resulted in porphyrin accumulation in the fetal liver, erythroid maturation arrest, and embryonic lethality due to profound anemia. Protoporphyrin IX synthesis in TMEM14C-deficient erythroid cells was blocked, leading to an accumulation of porphyrin precursors. The heme synthesis defect in TMEM14C-deficient cells was ameliorated with a protoporphyrin IX analog, indicating that TMEM14C primarily functions in the terminal steps of the heme synthesis pathway. Together, our data demonstrate that TMEM14C facilitates the import of protoporphyrinogen IX into the mitochondrial matrix for heme synthesis and subsequent hemoglobin production. Furthermore, the identification of TMEM14C as a protoporphyrinogen IX importer provides a genetic tool for further exploring erythropoiesis and congenital anemias.
- Published
- 2014
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30. Cpeb4-mediated translational regulatory circuitry controls terminal erythroid differentiation.
- Author
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Hu W, Yuan B, and Lodish HF
- Subjects
- Animals, Basic Helix-Loop-Helix Transcription Factors metabolism, DNA-Binding Proteins metabolism, Erythroblasts cytology, Feedback, Physiological, GATA1 Transcription Factor metabolism, Mice, Mice, Inbred C57BL, Protein Binding, Proto-Oncogene Proteins metabolism, RNA-Binding Proteins genetics, T-Cell Acute Lymphocytic Leukemia Protein 1, Transcription Factors metabolism, Transcriptional Activation, Erythroblasts metabolism, Erythropoiesis, Gene Expression Regulation, Developmental, RNA-Binding Proteins metabolism
- Abstract
While we have considerable understanding of the transcriptional networks controlling mammalian cell differentiation, our knowledge of posttranscriptional regulatory events is very limited. Using differentiation of primary erythroid cells as a model, we show that the sequence-specific mRNA-binding protein Cpeb4 is strongly induced by the erythroid-important transcription factors Gata1 and Tal1 and is essential for terminal erythropoiesis. By interacting with the translation initiation factor eIF3, Cpeb4 represses the translation of a large set of mRNAs, including its own mRNA. Thus, transcriptional induction and translational repression combine to form a negative feedback loop to control Cpeb4 protein levels within a specific range that is required for terminal erythropoiesis. Our study provides an example of how translational control is integrated with transcriptional regulation to precisely control gene expression during mammalian cell differentiation., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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31. Histones to the cytosol: exportin 7 is essential for normal terminal erythroid nuclear maturation.
- Author
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Hattangadi SM, Martinez-Morilla S, Patterson HC, Shi J, Burke K, Avila-Figueroa A, Venkatesan S, Wang J, Paulsen K, Görlich D, Murata-Hori M, and Lodish HF
- Subjects
- Animals, Cell Nucleus metabolism, Cytosol metabolism, Erythropoiesis genetics, Erythropoiesis physiology, Gene Knockdown Techniques, Karyopherins antagonists & inhibitors, Karyopherins genetics, Mice, Mice, Inbred C57BL, Nuclear Proteins blood, ran GTP-Binding Protein antagonists & inhibitors, ran GTP-Binding Protein genetics, Erythroblasts cytology, Erythroblasts metabolism, Histones blood, Karyopherins blood, ran GTP-Binding Protein blood
- Abstract
Global nuclear condensation, culminating in enucleation during terminal erythropoiesis, is poorly understood. Proteomic examination of extruded erythroid nuclei from fetal liver revealed a striking depletion of most nuclear proteins, suggesting that nuclear protein export had occurred. Expression of the nuclear export protein, Exportin 7 (Xpo7), is highly erythroid-specific, induced during erythropoiesis, and abundant in very late erythroblasts. Knockdown of Xpo7 in primary mouse fetal liver erythroblasts resulted in severe inhibition of chromatin condensation and enucleation but otherwise had little effect on erythroid differentiation, including hemoglobin accumulation. Nuclei in Xpo7-knockdown cells were larger and less dense than normal and accumulated most nuclear proteins as measured by mass spectrometry. Strikingly,many DNA binding proteins such as histones H2A and H3 were found to have migrated into the cytoplasm of normal late erythroblasts prior to and during enucleation, but not in Xpo7-knockdown cells. Thus, terminal erythroid maturation involves migration of histones into the cytoplasm via a process likely facilitated by Xpo7.
- Published
- 2014
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32. Muscleblind-like 1 (Mbnl1) regulates pre-mRNA alternative splicing during terminal erythropoiesis.
- Author
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Cheng AW, Shi J, Wong P, Luo KL, Trepman P, Wang ET, Choi H, Burge CB, and Lodish HF
- Subjects
- Animals, Blotting, Western, Carrier Proteins antagonists & inhibitors, Carrier Proteins metabolism, Cell Proliferation, DNA-Binding Proteins antagonists & inhibitors, DNA-Binding Proteins genetics, Exons genetics, HEK293 Cells, Humans, Immunoprecipitation, Mice, Protein Isoforms, RNA, Messenger genetics, RNA, Small Interfering genetics, RNA-Binding Proteins antagonists & inhibitors, RNA-Binding Proteins genetics, Real-Time Polymerase Chain Reaction, Reverse Transcriptase Polymerase Chain Reaction, Alternative Splicing, Carrier Proteins genetics, Cell Differentiation, DNA-Binding Proteins metabolism, Erythropoiesis physiology, Gene Expression Regulation, RNA Precursors genetics, RNA-Binding Proteins metabolism
- Abstract
The scope and roles of regulated isoform gene expression during erythroid terminal development are poorly understood. We identified hundreds of differentiation-associated isoform changes during terminal erythropoiesis. Sequences surrounding cassette exons of skipped exon events are enriched for motifs bound by the Muscleblind-like (MBNL) family of splicing factors. Knockdown of Mbnl1 in cultured murine fetal liver erythroid progenitors resulted in a strong block in erythroid differentiation and disrupted the developmentally regulated exon skipping of Ndel1 mRNA, which is bound by MBNL1 and critical for erythroid terminal proliferation. These findings reveal an unanticipated scope of the alternative splicing program and the importance of Mbnl1 during erythroid terminal differentiation., (© 2014 by The American Society of Hematology.)
- Published
- 2014
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33. Engineered red blood cells as carriers for systemic delivery of a wide array of functional probes.
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Shi J, Kundrat L, Pishesha N, Bilate A, Theile C, Maruyama T, Dougan SK, Ploegh HL, and Lodish HF
- Subjects
- Animals, Cells, Cultured, Erythrocyte Membrane genetics, Humans, Mice, Cell Differentiation, Cell Engineering, Erythroblasts metabolism, Erythrocyte Membrane metabolism, Reticulocytes metabolism
- Abstract
We developed modified RBCs to serve as carriers for systemic delivery of a wide array of payloads. These RBCs contain modified proteins on their plasma membrane, which can be labeled in a sortase-catalyzed reaction under native conditions without inflicting damage to the target membrane or cell. Sortase accommodates a wide range of natural and synthetic payloads that allow modification of RBCs with substituents that cannot be encoded genetically. As proof of principle, we demonstrate site-specific conjugation of biotin to in vitro-differentiated mouse erythroblasts as well as to mature mouse RBCs. Thus modified, RBCs remain in the bloodstream for up to 28 d. A single domain antibody attached enzymatically to RBCs enables them to bind specifically to target cells that express the antibody target. We extend these experiments to human RBCs and demonstrate efficient sortase-mediated labeling of in vitro-differentiated human reticulocytes.
- Published
- 2014
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34. Altered translation of GATA1 in Diamond-Blackfan anemia.
- Author
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Ludwig LS, Gazda HT, Eng JC, Eichhorn SW, Thiru P, Ghazvinian R, George TI, Gotlib JR, Beggs AH, Sieff CA, Lodish HF, Lander ES, and Sankaran VG
- Subjects
- Humans, Mutation, RNA, Messenger genetics, Ribosomal Proteins genetics, Anemia, Diamond-Blackfan genetics, GATA1 Transcription Factor genetics, Protein Biosynthesis
- Abstract
Ribosomal protein haploinsufficiency occurs in diverse human diseases including Diamond-Blackfan anemia (DBA), congenital asplenia and T cell leukemia. Yet, how mutations in genes encoding ubiquitously expressed proteins such as these result in cell-type- and tissue-specific defects remains unknown. Here, we identify mutations in GATA1, encoding the critical hematopoietic transcription factor GATA-binding protein-1, that reduce levels of full-length GATA1 protein and cause DBA in rare instances. We show that ribosomal protein haploinsufficiency, the more common cause of DBA, can lead to decreased GATA1 mRNA translation, possibly resulting from a higher threshold for initiation of translation of this mRNA in comparison with other mRNAs. In primary hematopoietic cells from patients with mutations in RPS19, encoding ribosomal protein S19, the amplitude of a transcriptional signature of GATA1 target genes was globally and specifically reduced, indicating that the activity, but not the mRNA level, of GATA1 is decreased in patients with DBA associated with mutations affecting ribosomal proteins. Moreover, the defective hematopoiesis observed in patients with DBA associated with ribosomal protein haploinsufficiency could be partially overcome by increasing GATA1 protein levels. Our results provide a paradigm by which selective defects in translation due to mutations affecting ubiquitous ribosomal proteins can result in human disease.
- Published
- 2014
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35. Global analysis of induced transcription factors and cofactors identifies Tfdp2 as an essential coregulator during terminal erythropoiesis.
- Author
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Chen C and Lodish HF
- Subjects
- Animals, Cell Cycle, Cell Proliferation, Cell Size, Cells, Cultured, Computational Biology, DNA-Binding Proteins genetics, Flow Cytometry, Gene Expression Profiling, Gene Knockdown Techniques, Mice, Models, Biological, DNA-Binding Proteins metabolism, Erythroid Cells cytology, Erythropoiesis drug effects, Transcription Factors genetics, Transcription Factors metabolism
- Abstract
Key transcriptional regulators of terminal erythropoiesis, such as GATA-binding factor 1 (GATA1) and T-cell acute lymphocytic leukemia protein 1 (TAL1), have been well characterized, but transcription factors and cofactors and their expression modulations have not yet been explored on a global scale. Here, we use global gene expression analysis to identify 28 transcription factors and 19 transcriptional cofactors induced during terminal erythroid differentiation whose promoters are enriched for binding by GATA1 and TAL1. Utilizing protein-protein interaction databases to identify cofactors for each transcription factor, we pinpoint several co-induced pairs, of which E2f2 and its cofactor transcription factor Dp-2 (Tfdp2) were the most highly induced. TFDP2 is a critical cofactor required for proper cell cycle control and gene expression. GATA1 and TAL1 are bound to the regulatory regions of Tfdp2 and upregulate its expression and knockdown of Tfdp2 results in significantly reduced rates of proliferation as well as reduced upregulation of many erythroid-important genes. Loss of Tfdp2 also globally inhibits the normal downregulation of many E2F2 target genes, including those that regulate the cell cycle, causing cells to accumulate in S phase and resulting in increased erythrocyte size. Our findings highlight the importance of TFDP2 in coupling the erythroid cell cycle with terminal differentiation and validate this study as a resource for future work on elucidating the role of diverse transcription factors and coregulators in erythropoiesis., (Copyright © 2014 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)
- Published
- 2014
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36. Transcriptional divergence and conservation of human and mouse erythropoiesis.
- Author
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Pishesha N, Thiru P, Shi J, Eng JC, Sankaran VG, and Lodish HF
- Subjects
- Animals, Blotting, Western, Erythropoiesis genetics, Flow Cytometry, Gene Expression Profiling, Humans, Mice, Microarray Analysis, Species Specificity, Erythroid Precursor Cells metabolism, Erythropoiesis physiology, Gene Expression Regulation, Developmental genetics, Transcriptome genetics
- Abstract
Mouse models have been used extensively for decades and have been instrumental in improving our understanding of mammalian erythropoiesis. Nonetheless, there are several examples of variation between human and mouse erythropoiesis. We performed a comparative global gene expression study using data from morphologically identical stage-matched sorted populations of human and mouse erythroid precursors from early to late erythroblasts. Induction and repression of major transcriptional regulators of erythropoiesis, as well as major erythroid-important proteins, are largely conserved between the species. In contrast, at a global level we identified a significant extent of divergence between the species, both at comparable stages and in the transitions between stages, especially for the 500 most highly expressed genes during development. This suggests that the response of multiple developmentally regulated genes to key erythroid transcriptional regulators represents an important modification that has occurred in the course of erythroid evolution. In developing a systematic framework to understand and study conservation and divergence between human and mouse erythropoiesis, we show how mouse models can fail to mimic specific human diseases and provide predictions for translating findings from mouse models to potential therapies for human disease.
- Published
- 2014
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37. Topological organization of multichromosomal regions by the long intergenic noncoding RNA Firre.
- Author
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Hacisuleyman E, Goff LA, Trapnell C, Williams A, Henao-Mejia J, Sun L, McClanahan P, Hendrickson DG, Sauvageau M, Kelley DR, Morse M, Engreitz J, Lander ES, Guttman M, Lodish HF, Flavell R, Raj A, and Rinn JL
- Subjects
- Animals, Base Sequence, Chromatin metabolism, Chromosomes ultrastructure, Embryonic Stem Cells, Female, Humans, Male, Mice, Molecular Sequence Data, RNA, Long Noncoding analysis, RNA, Long Noncoding chemistry, Sequence Analysis, RNA, X Chromosome Inactivation, Chromosomes metabolism, Models, Genetic, RNA, Long Noncoding physiology
- Abstract
RNA, including long noncoding RNA (lncRNA), is known to be an abundant and important structural component of the nuclear matrix. However, the molecular identities, functional roles and localization dynamics of lncRNAs that influence nuclear architecture remain poorly understood. Here, we describe one lncRNA, Firre, that interacts with the nuclear-matrix factor hnRNPU through a 156-bp repeating sequence and localizes across an ~5-Mb domain on the X chromosome. We further observed Firre localization across five distinct trans-chromosomal loci, which reside in spatial proximity to the Firre genomic locus on the X chromosome. Both genetic deletion of the Firre locus and knockdown of hnRNPU resulted in loss of colocalization of these trans-chromosomal interacting loci. Thus, our data suggest a model in which lncRNAs such as Firre can interface with and modulate nuclear architecture across chromosomes.
- Published
- 2014
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38. Global discovery of erythroid long noncoding RNAs reveals novel regulators of red cell maturation.
- Author
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Alvarez-Dominguez JR, Hu W, Yuan B, Shi J, Park SS, Gromatzky AA, van Oudenaarden A, and Lodish HF
- Subjects
- Animals, Cell Nucleus metabolism, Enhancer Elements, Genetic, Epigenesis, Genetic, Erythroid Cells cytology, Erythropoiesis genetics, Gene Expression Profiling, Genome, Humans, In Situ Hybridization, Fluorescence, K562 Cells, Liver metabolism, Mice, Mutation, Oligonucleotide Array Sequence Analysis, Retroviridae metabolism, T-Cell Acute Lymphocytic Leukemia Protein 1, Transcription Factors, Basic Helix-Loop-Helix Transcription Factors metabolism, Erythrocytes cytology, GATA1 Transcription Factor metabolism, Kruppel-Like Transcription Factors metabolism, Proto-Oncogene Proteins metabolism, RNA, Long Noncoding
- Abstract
Erythropoiesis is regulated at multiple levels to ensure the proper generation of mature red cells under multiple physiological conditions. To probe the contribution of long noncoding RNAs (lncRNAs) to this process, we examined >1 billion RNA-seq reads of polyadenylated and nonpolyadenylated RNA from differentiating mouse fetal liver red blood cells and identified 655 lncRNA genes including not only intergenic, antisense, and intronic but also pseudogene and enhancer loci. More than 100 of these genes are previously unrecognized and highly erythroid specific. By integrating genome-wide surveys of chromatin states, transcription factor occupancy, and tissue expression patterns, we identify multiple lncRNAs that are dynamically expressed during erythropoiesis, show epigenetic regulation, and are targeted by key erythroid transcription factors GATA1, TAL1, or KLF1. We focus on 12 such candidates and find that they are nuclear-localized and exhibit complex developmental expression patterns. Depleting them severely impaired erythrocyte maturation, inhibiting cell size reduction and subsequent enucleation. One of them, alncRNA-EC7, is transcribed from an enhancer and is specifically needed for activation of the neighboring gene encoding BAND 3. Our study provides an annotated catalog of erythroid lncRNAs, readily available through an online resource, and shows that diverse types of lncRNAs participate in the regulatory circuitry underlying erythropoiesis.
- Published
- 2014
- Full Text
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39. Analysis of in vitro insulin-resistance models and their physiological relevance to in vivo diet-induced adipose insulin resistance.
- Author
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Lo KA, Labadorf A, Kennedy NJ, Han MS, Yap YS, Matthews B, Xin X, Sun L, Davis RJ, Lodish HF, and Fraenkel E
- Subjects
- Animals, Disease Models, Animal, Humans, Mice, Adipose Tissue metabolism, Insulin Resistance physiology, Tumor Necrosis Factor-alpha physiology
- Abstract
Diet-induced obesity (DIO) predisposes individuals to insulin resistance, and adipose tissue has a major role in the disease. Insulin resistance can be induced in cultured adipocytes by a variety of treatments, but what aspects of the in vivo responses are captured by these models remains unknown. We use global RNA sequencing to investigate changes induced by TNF-α, hypoxia, dexamethasone, high insulin, and a combination of TNF-α and hypoxia, comparing the results to the changes in white adipose tissue from DIO mice. We found that different in vitro models capture distinct features of DIO adipose insulin resistance, and a combined treatment of TNF-α and hypoxia is most able to mimic the in vivo changes. Using genome-wide DNase I hypersensitivity followed by sequencing, we further examined the transcriptional regulation of TNF-α-induced insulin resistance, and we found that C/EPBβ is a potential key regulator of adipose insulin resistance., (Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
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40. MicroRNA-126-mediated control of cell fate in B-cell myeloid progenitors as a potential alternative to transcriptional factors.
- Author
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Okuyama K, Ikawa T, Gentner B, Hozumi K, Harnprasopwat R, Lu J, Yamashita R, Ha D, Toyoshima T, Chanda B, Kawamata T, Yokoyama K, Wang S, Ando K, Lodish HF, Tojo A, Kawamoto H, and Kotani A
- Subjects
- Analysis of Variance, B-Lymphocytes metabolism, Blotting, Western, Bone Marrow Transplantation, Cell Line, Tumor, Cell Lineage immunology, DNA Primers, Genetic Vectors genetics, Humans, Luciferases, Myeloid Progenitor Cells, Oligonucleotides genetics, Statistics, Nonparametric, Trans-Activators metabolism, Transcription Factor 3 metabolism, Cell Lineage genetics, Gene Expression Profiling, Leukemia, B-Cell metabolism, MicroRNAs metabolism
- Abstract
Lineage specification is thought to be largely regulated at the level of transcription, where lineage-specific transcription factors drive specific cell fates. MicroRNAs (miR), vital to many cell functions, act posttranscriptionally to decrease the expression of target mRNAs. MLL-AF4 acute lymphocytic leukemia exhibits both myeloid and B-cell surface markers, suggesting that the transformed cells are B-cell myeloid progenitor cells. Through gain- and loss-of-function experiments, we demonstrated that microRNA 126 (miR-126) drives B-cell myeloid biphenotypic leukemia differentiation toward B cells without changing expression of E2A immunoglobulin enhancer-binding factor E12/E47 (E2A), early B-cell factor 1 (EBF1), or paired box protein 5, which are critical transcription factors in B-lymphopoiesis. Similar induction of B-cell differentiation by miR-126 was observed in normal hematopoietic cells in vitro and in vivo in uncommitted murine c-Kit(+)Sca1(+)Lineage(-) cells, with insulin regulatory subunit-1 acting as a target of miR-126. Importantly, in EBF1-deficient hematopoietic progenitor cells, which fail to differentiate into B cells, miR-126 significantly up-regulated B220, and induced the expression of B-cell genes, including recombination activating genes-1/2 and CD79a/b. These data suggest that miR-126 can at least partly rescue B-cell development independently of EBF1. These experiments show that miR-126 regulates myeloid vs. B-cell fate through an alternative machinery, establishing the critical role of miRNAs in the lineage specification of multipotent mammalian cells.
- Published
- 2013
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41. ZFP36L2 is required for self-renewal of early burst-forming unit erythroid progenitors.
- Author
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Zhang L, Prak L, Rayon-Estrada V, Thiru P, Flygare J, Lim B, and Lodish HF
- Subjects
- Animals, Cell Count, Cell Lineage, Down-Regulation, Erythropoiesis genetics, Gene Knockdown Techniques, Glucocorticoids pharmacology, Mice, RNA, Messenger genetics, RNA, Messenger metabolism, RNA-Binding Proteins metabolism, Receptors, Glucocorticoid agonists, Receptors, Glucocorticoid metabolism, Stress, Physiological, Tristetraprolin deficiency, Tristetraprolin genetics, Cell Division drug effects, Erythroid Precursor Cells cytology, Erythroid Precursor Cells metabolism, Tristetraprolin metabolism
- Abstract
Stem cells and progenitors in many lineages undergo self-renewing divisions, but the extracellular and intracellular proteins that regulate this process are largely unknown. Glucocorticoids stimulate red blood cell formation by promoting self-renewal of early burst-forming unit-erythroid (BFU-E) progenitors. Here we show that the RNA-binding protein ZFP36L2 is a transcriptional target of the glucocorticoid receptor (GR) in BFU-Es and is required for BFU-E self-renewal. ZFP36L2 is normally downregulated during erythroid differentiation from the BFU-E stage, but its expression is maintained by all tested GR agonists that stimulate BFU-E self-renewal, and the GR binds to several potential enhancer regions of ZFP36L2. Knockdown of ZFP36L2 in cultured BFU-E cells did not affect the rate of cell division but disrupted glucocorticoid-induced BFU-E self-renewal, and knockdown of ZFP36L2 in transplanted erythroid progenitors prevented expansion of erythroid lineage progenitors normally seen following induction of anaemia by phenylhydrazine treatment. ZFP36L2 preferentially binds to messenger RNAs that are induced or maintained at high expression levels during terminal erythroid differentiation and negatively regulates their expression levels. ZFP36L2 therefore functions as part of a molecular switch promoting BFU-E self-renewal and a subsequent increase in the total numbers of colony-forming unit-erythroid (CFU-E) progenitors and erythroid cells that are generated.
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- 2013
- Full Text
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42. Regulated ADAM17-dependent EGF family ligand release by substrate-selecting signaling pathways.
- Author
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Dang M, Armbruster N, Miller MA, Cermeno E, Hartmann M, Bell GW, Root DE, Lauffenburger DA, Lodish HF, and Herrlich A
- Subjects
- ADAM Proteins genetics, ADAM17 Protein, Amphiregulin, Angiotensin II pharmacology, Blotting, Western, Cell Line, Tumor, EGF Family of Proteins, Enzyme Activation drug effects, Flow Cytometry, Glycoproteins genetics, Glycoproteins metabolism, HEK293 Cells, Humans, Intercellular Signaling Peptides and Proteins genetics, Intercellular Signaling Peptides and Proteins metabolism, Isoenzymes metabolism, Jurkat Cells, Ligands, Phosphorylation, Protein Kinase C metabolism, Proteins metabolism, Proteolysis drug effects, RNA Interference, Serine genetics, Serine metabolism, Substrate Specificity, Tetradecanoylphorbol Acetate pharmacology, Transforming Growth Factor alpha genetics, ADAM Proteins metabolism, Epidermal Growth Factor metabolism, Signal Transduction, Transforming Growth Factor alpha metabolism
- Abstract
Ectodomain cleavage of cell-surface proteins by A disintegrin and metalloproteinases (ADAMs) is highly regulated, and its dysregulation has been linked to many diseases. ADAM10 and ADAM17 cleave most disease-relevant substrates. Broad-spectrum metalloprotease inhibitors have failed clinically, and targeting the cleavage of a specific substrate has remained impossible. It is therefore necessary to identify signaling intermediates that determine substrate specificity of cleavage. We show here that phorbol ester or angiotensin II-induced proteolytic release of EGF family members may not require a significant increase in ADAM17 protease activity. Rather, inducers activate a signaling pathway using PKC-α and the PKC-regulated protein phosphatase 1 inhibitor 14D that is required for ADAM17 cleavage of TGF-α, heparin-binding EGF, and amphiregulin. A second pathway involving PKC-δ is required for neuregulin (NRG) cleavage, and, indeed, PKC-δ phosphorylation of serine 286 in the NRG cytosolic domain is essential for induced NRG cleavage. Thus, signaling-mediated substrate selection is clearly distinct from regulation of enzyme activity, an important mechanism that offers itself for application in disease.
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- 2013
- Full Text
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43. Fetal hepatic progenitors support long-term expansion of hematopoietic stem cells.
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Chou S, Flygare J, and Lodish HF
- Subjects
- Animals, Calcium-Binding Proteins, Cell Adhesion drug effects, Cells, Cultured, Coculture Techniques, Culture Media, Conditioned pharmacology, Culture Media, Serum-Free pharmacology, Cytokines pharmacology, Fetus, Flow Cytometry, Green Fluorescent Proteins genetics, Green Fluorescent Proteins metabolism, Hematopoietic Stem Cells metabolism, Immunohistochemistry, Intercellular Signaling Peptides and Proteins metabolism, Liver cytology, Liver embryology, Mice, Mice, Inbred C57BL, Mice, Transgenic, Stem Cells drug effects, Stem Cells metabolism, Time Factors, Cell Culture Techniques methods, Cell Proliferation, Hematopoietic Stem Cells cytology, Stem Cells cytology
- Abstract
We have developed a coculture system that establishes DLK(+) fetal hepatic progenitors as the authentic supportive cells for expansion of hematopoietic stem (HSCs) and progenitor cells. In 1-week cultures supplemented with serum and supportive cytokines, both cocultured DLK(+) fetal hepatic progenitors and their conditioned medium supported rapid expansion of hematopoietic progenitors and a small increase in HSC numbers. In 2- and 3-week cultures DLK(+) cells, but not their conditioned medium, continuously and significantly (>20-fold) expanded both hematopoietic stem and progenitor cells. Physical contact between HSCs and DLK(+) cells was crucial to maintaining this long-term expansion. Similar HSC expansion (approximately sevenfold) was achieved in cocultures using a serum-free, low cytokine- containing medium. In contrast, DLK(-) cells are incapable of expanding hematopoietic cells, demonstrating that hepatic progenitors are the principle supportive cells for HSC expansion in the fetal liver., (Copyright © 2013 ISEH - Society for Hematology and Stem Cells. Published by Elsevier Inc. All rights reserved.)
- Published
- 2013
- Full Text
- View/download PDF
44. Snx3 regulates recycling of the transferrin receptor and iron assimilation.
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Chen C, Garcia-Santos D, Ishikawa Y, Seguin A, Li L, Fegan KH, Hildick-Smith GJ, Shah DI, Cooney JD, Chen W, King MJ, Yien YY, Schultz IJ, Anderson H, Dalton AJ, Freedman ML, Kingsley PD, Palis J, Hattangadi SM, Lodish HF, Ward DM, Kaplan J, Maeda T, Ponka P, and Paw BH
- Subjects
- Analysis of Variance, Animals, Blotting, Western, Cells, Cultured, Fluorescein-5-isothiocyanate, Fluorescent Antibody Technique, Gene Silencing, Mice, Sorting Nexins genetics, Zebrafish, Anemia genetics, Iron metabolism, Receptors, Transferrin metabolism, Sorting Nexins metabolism
- Abstract
Sorting of endocytic ligands and receptors is critical for diverse cellular processes. The physiological significance of endosomal sorting proteins in vertebrates, however, remains largely unknown. Here we report that sorting nexin 3 (Snx3) facilitates the recycling of transferrin receptor (Tfrc) and thus is required for the proper delivery of iron to erythroid progenitors. Snx3 is highly expressed in vertebrate hematopoietic tissues. Silencing of Snx3 results in anemia and hemoglobin defects in vertebrates due to impaired transferrin (Tf)-mediated iron uptake and its accumulation in early endosomes. This impaired iron assimilation can be complemented with non-Tf iron chelates. We show that Snx3 and Vps35, a component of the retromer, interact with Tfrc to sort it to the recycling endosomes. Our findings uncover a role of Snx3 in regulating Tfrc recycling, iron homeostasis, and erythropoiesis. Thus, the identification of Snx3 provides a genetic tool for exploring erythropoiesis and disorders of iron metabolism., (Copyright © 2013 Elsevier Inc. All rights reserved.)
- Published
- 2013
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45. Long noncoding RNAs regulate adipogenesis.
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Sun L, Goff LA, Trapnell C, Alexander R, Lo KA, Hacisuleyman E, Sauvageau M, Tazon-Vega B, Kelley DR, Hendrickson DG, Yuan B, Kellis M, Lodish HF, and Rinn JL
- Subjects
- Animals, Gene Expression Profiling, Gene Expression Regulation, Gene Knockdown Techniques, Information Theory, Male, Mice, Oligonucleotide Array Sequence Analysis, Open Reading Frames genetics, Phenotype, RNA, Long Noncoding genetics, Reproducibility of Results, Transcriptome genetics, Adipogenesis genetics, RNA, Long Noncoding metabolism
- Abstract
The prevalence of obesity has led to a surge of interest in understanding the detailed mechanisms underlying adipocyte development. Many protein-coding genes, mRNAs, and microRNAs have been implicated in adipocyte development, but the global expression patterns and functional contributions of long noncoding RNA (lncRNA) during adipogenesis have not been explored. Here we profiled the transcriptome of primary brown and white adipocytes, preadipocytes, and cultured adipocytes and identified 175 lncRNAs that are specifically regulated during adipogenesis. Many lncRNAs are adipose-enriched, strongly induced during adipogenesis, and bound at their promoters by key transcription factors such as peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (CEBPα). RNAi-mediated loss of function screens identified functional lncRNAs with varying impact on adipogenesis. Collectively, we have identified numerous lncRNAs that are functionally required for proper adipogenesis.
- Published
- 2013
- Full Text
- View/download PDF
46. Regulation of mammalian cell differentiation by long non-coding RNAs.
- Author
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Hu W, Alvarez-Dominguez JR, and Lodish HF
- Subjects
- Animals, Embryonic Stem Cells cytology, Embryonic Stem Cells metabolism, Gene Expression Regulation, Developmental, Genes, Homeobox, Humans, Induced Pluripotent Stem Cells cytology, Induced Pluripotent Stem Cells metabolism, Mammals, RNA, Long Noncoding classification, RNA, Long Noncoding genetics, Cell Differentiation, RNA, Long Noncoding metabolism
- Abstract
Differentiation of specialized cell types from stem and progenitor cells is tightly regulated at several levels, both during development and during somatic tissue homeostasis. Many long non-coding RNAs have been recognized as an additional layer of regulation in the specification of cellular identities; these non-coding species can modulate gene-expression programmes in various biological contexts through diverse mechanisms at the transcriptional, translational or messenger RNA stability levels. Here, we summarize findings that implicate long non-coding RNAs in the control of mammalian cell differentiation. We focus on several representative differentiation systems and discuss how specific long non-coding RNAs contribute to the regulation of mammalian development.
- Published
- 2012
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47. MicroRNAs in erythroid and megakaryocytic differentiation and megakaryocyte-erythroid progenitor lineage commitment.
- Author
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Zhang L, Sankaran VG, and Lodish HF
- Subjects
- Cell Lineage, Humans, MicroRNAs genetics, Cell Differentiation physiology, Erythrocytes cytology, Megakaryocytes cytology, MicroRNAs physiology
- Abstract
MicroRNAs (miRNAs) are a class of small regulatory noncoding RNAs that modulate the expression of their target genes through either mRNA degradation or inhibition of protein translation. In recent years, miRNAs have been shown to be critical regulators of hematopoiesis and have important roles in the differentiation of specific lineages. Here, we summarize our current understanding of miRNAs involved in hematopoiesis with a focus on the role of miRNAs in regulating erythroid and megakaryocytic differentiation and megakaryocyte-erythroid progenitor lineage commitment.
- Published
- 2012
- Full Text
- View/download PDF
48. MicroRNA-125b transforms myeloid cell lines by repressing multiple mRNA.
- Author
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Bousquet M, Nguyen D, Chen C, Shields L, and Lodish HF
- Subjects
- Animals, Apoptosis genetics, Cell Differentiation genetics, Cell Transformation, Neoplastic genetics, Cell Transformation, Neoplastic pathology, HL-60 Cells, Humans, Leukemia, Promyelocytic, Acute genetics, Leukemia, Promyelocytic, Acute pathology, Mice, Mice, Nude, MicroRNAs genetics, Myelodysplastic Syndromes genetics, Myelodysplastic Syndromes metabolism, Myelodysplastic Syndromes pathology, Myeloid Cells pathology, Neoplasm Proteins genetics, Neoplasm Proteins metabolism, Neoplastic Stem Cells pathology, RNA, Neoplasm genetics, Stem Cell Transplantation, Transplantation, Heterologous, Cell Transformation, Neoplastic metabolism, Leukemia, Promyelocytic, Acute metabolism, MicroRNAs metabolism, Myeloid Cells metabolism, Neoplastic Stem Cells metabolism, RNA, Neoplasm metabolism
- Abstract
Background: We previously described a t(2;11)(p21;q23) chromosomal translocation found in patients with myelodysplasia or acute myeloid leukemia that leads to over-expression of the microRNA miR-125b, and we showed that transplantation of mice with murine stem/progenitor cells overexpressing miR-125b is able to induce leukemia. In this study, we investigated the mechanism of myeloid transformation by miR-125b., Design and Methods: To investigate the consequences of miR-125b over-expression on myeloid differentiation, apoptosis and proliferation, we used the NB4 and HL60 human promyelocytic cell lines and the 32Dclone3 murine promyelocytic cell line. To test whether miR-125b is able to transform myeloid cells, we used the non-tumorigenic and interleukin-3-dependent 32Dclone3 cell line over-expressing miR-125b, in xenograft experiments in nude mice and in conditions of interleukin-3 deprivation. To identify new miR-125b targets, we compared, by RNA-sequencing, the transcriptome of cell lines that do or do not over-express miR-125b., Results: We showed that miR-125b over-expression blocks apoptosis and myeloid differentiation and enhances proliferation in both species. More importantly, we demonstrated that miR-125b is able to transform the 32Dclone3 cell line by conferring growth independence from interleukin-3; xenograft experiments showed that these cells form tumors in nude mice. Using RNA-sequencing and quantitative real-time polymerase chain reaction experiments, we identified multiple miR-125b targets. We demonstrated that ABTB1, an anti-proliferative factor, is a new direct target of miR-125b and we confirmed that CBFB, a transcription factor involved in hematopoiesis, is also targeted by miR-125b. MiR-125b controls apoptosis by down-regulating genes involved in the p53 pathway including BAK1 and TP53INP1., Conclusions: This study demonstrates that in a myeloid context, miR-125b is an oncomiR able to transform cell lines. miR-125b blocks myeloid differentiation in part by targeting CBFB, blocks apoptosis through down-regulation of multiple genes involved in the p53 pathway, and confers a proliferative advantage to human and mouse myeloid cell lines in part by targeting ABTB1.
- Published
- 2012
- Full Text
- View/download PDF
49. Translational control of protein synthesis: the early years.
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Lodish HF
- Subjects
- Animals, Bacteriophages metabolism, Cell Membrane metabolism, Globins biosynthesis, History, 20th Century, Humans, Membrane Proteins biosynthesis, Molecular Biology methods, Protein Folding, RNA, Messenger metabolism, Molecular Biology history, Protein Biosynthesis physiology
- Abstract
For the past fifty-five years, much of my research has focused on the function and biogenesis of red blood cells, including the cloning and study of many membrane proteins such as glucose and anion transporters and the erythropoietin receptor. We have also elucidated the mechanisms of membrane insertion, folding, and maturation of many plasma membrane and secreted proteins. Despite all of this work and more, I remain extremely proud of our very early work on the regulation of mRNA translation: work on bacteriophage f2 RNA in the 1960s and on translation of α- and β-globin mRNAs in the early 1970s. Using techniques hopelessly antiquated by today's standards, we correctly elucidated many important aspects of translational control, and I thought readers would be interested in learning how we did these experiments.
- Published
- 2012
- Full Text
- View/download PDF
50. Cyclin D3 coordinates the cell cycle during differentiation to regulate erythrocyte size and number.
- Author
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Sankaran VG, Ludwig LS, Sicinska E, Xu J, Bauer DE, Eng JC, Patterson HC, Metcalf RA, Natkunam Y, Orkin SH, Sicinski P, Lander ES, and Lodish HF
- Subjects
- Animals, Cell Count, Cell Size, Cells, Cultured, Cyclin D3 genetics, Erythropoiesis physiology, Gene Expression Regulation, Gene Knockdown Techniques, Humans, K562 Cells, Mice, Mice, Knockout, Cell Cycle physiology, Cell Differentiation, Cyclin D3 metabolism, Erythrocytes cytology, Erythrocytes metabolism
- Abstract
Genome-wide association studies (GWASs) have identified a genetic variant of moderate effect size at 6p21.1 associated with erythrocyte traits in humans. We show that this variant affects an erythroid-specific enhancer of CCND3. A Ccnd3 knockout mouse phenocopies these erythroid phenotypes, with a dramatic increase in erythrocyte size and a concomitant decrease in erythrocyte number. By examining human and mouse primary erythroid cells, we demonstrate that the CCND3 gene product cyclin D3 regulates the number of cell divisions that erythroid precursors undergo during terminal differentiation, thereby controlling erythrocyte size and number. We illustrate how cell type-specific specialization can occur for general cell cycle components-a finding resulting from the biological follow-up of unbiased human genetic studies.
- Published
- 2012
- Full Text
- View/download PDF
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