18 results on '"Sheng, X. Rebecca"'
Search Results
2. Evaluation of low volume sampling devices for a pharmacodynamic biomarker analysis: Challenges and solutions
- Author
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Yang, Xiaoyun, Logis, Evelin, Williams, Kathi, Sheng, X. Rebecca, and Fischer, Saloumeh K.
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- 2024
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3. Utilizing PK and PD Biomarkers to Guide the First-in-Human Starting Dose Selection of MTBT1466A: A Novel Humanized Monoclonal Anti-TGFβ3 Antibody for the Treatment of Fibrotic Diseases
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Yadav, Rajbharan, Sukumaran, Siddharth, Lutman, Jeff, Mitra, Mayur S., Halpern, Wendy, Sun, Tianhe, Setiadi, A. Francesca, Neighbors, Margaret, Sheng, X. Rebecca, Yip, Victor, Shen, Ben-Quan, Liu, Chang, Han, Lyrialle, Ovacik, Ayse Meric, Wu, Yan, Glickstein, Sara, Kunder, Rebecca, Arron, Joseph R., Pan, Lin, Kamath, Amrita V., and Stefanich, Eric G.
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- 2023
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4. Biomarkers of fibrosis, inflammation, and extracellular matrix in the phase 3 trial of tocilizumab in systemic sclerosis
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Sheng, X. Rebecca, Gao, Xia, Schiffman, Courtney, Jiang, Jenny, Ramalingam, Thirumalai R., Lin, Celia J.F., Khanna, Dinesh, and Neighbors, Margaret
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- 2023
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5. Association study of human leukocyte antigen (HLA) variants and idiopathic pulmonary fibrosis
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Guillen-Guio, Beatriz, primary, Paynton, Megan L., additional, Allen, Richard J., additional, Chin, Daniel P.W., additional, Donoghue, Lauren J., additional, Stockwell, Amy, additional, Leavy, Olivia C., additional, Hernandez-Beeftink, Tamara, additional, Reynolds, Carl, additional, Cullinan, Paul, additional, Martinez, Fernando, additional, Booth, Helen L., additional, Fahy, William A., additional, Hall, Ian P., additional, Hart, Simon P., additional, Hill, Mike R., additional, Hirani, Nik, additional, Hubbard, Richard B., additional, McAnulty, Robin J., additional, Millar, Ann B., additional, Navaratnam, Vidya, additional, Oballa, Eunice, additional, Parfrey, Helen, additional, Saini, Gauri, additional, Sayers, Ian, additional, Tobin, Martin D., additional, Whyte, Moira K. B., additional, Adegunsoye, Ayodeji, additional, Kaminski, Naftali, additional, Ma, Shwu-Fan, additional, Strek, Mary E., additional, Zhang, Yingze, additional, Fingerlin, Tasha E., additional, Molina-Molina, Maria, additional, Neighbors, Margaret, additional, Sheng, X. Rebecca, additional, Oldham, Justin M., additional, Maher, Toby M., additional, Molyneaux, Philip L., additional, Flores, Carlos, additional, Noth, Imre, additional, Schwartz, David A., additional, Yaspan, Brian L., additional, Jenkins, R. Gisli, additional, Wain, Louise V., additional, and Hollox, Edward J., additional
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- 2023
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6. Prognostic and predictive biomarkers for patients with idiopathic pulmonary fibrosis treated with pirfenidone: post-hoc assessment of the CAPACITY and ASCEND trials
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Neighbors, Margaret, Cabanski, Christopher R, Ramalingam, Thirumalai R, Sheng, X Rebecca, Tew, Gaik W, Gu, Chunyan, Jia, Guiquan, Peng, Kun, Ray, Jill M, Ley, Brett, Wolters, Paul J, Collard, Harold R, and Arron, Joseph R
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- 2018
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7. Jak-STAT regulation of male germline stem cell establishment during Drosophila embryogenesis
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Sheng, X. Rebecca, Posenau, Trevor, Gumulak-Smith, Juliann J., Matunis, Erika, Van Doren, Mark, and Wawersik, Matthew
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Stem cells ,Drosophila ,Biological sciences - Abstract
To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2009.07.031 Byline: X. Rebecca Sheng (a), Trevor Posenau (b), Juliann J. Gumulak-Smith (b), Erika Matunis (a), Mark Van Doren (c), Matthew Wawersik (b)(c) Keywords: Primordial germ cell; Germline; Spermatogonia; Niche; Jak-STAT; Gonad; Stem cell Abstract: Germline stem cells (GSCs) in Drosophila are descendants of primordial germ cells (PGCs) specified during embryogenesis. The precise timing of GSC establishment in the testis has not been determined, nor is it known whether mechanisms that control GSC maintenance in the adult are involved in GSC establishment. Here, we determine that PGCs in the developing male gonad first become GSCs at the embryo to larval transition. This coincides with formation of the embryonic hub; the critical signaling center that regulates adult GSC behavior within the stem cell microenvironment (niche). We find that the Jak-STAT signaling pathway is activated in a subset of PGCs that associate with the newly-formed embryonic hub. These PGCs express GSC markers and function like GSCs, while PGCs that do not associate with the hub begin to differentiate. In the absence of Jak-STAT activation, PGCs adjacent to the hub fail to exhibit the characteristics of GSCs, while ectopic activation of the Jak-STAT pathway prevents differentiation. These findings show that stem cell formation is closely linked to development of the stem cell niche, and suggest that Jak-STAT signaling is required for initial establishment of the GSC population in developing testes. Author Affiliation: (a) Department of Cell Biology, 725 N. Wolfe Street, The Johns Hopkins University, School of Medicine, Baltimore, MD 21205, USA (b) Department of Biology, Integrated Science Center, Rm 2139, The College of William and Mary, Williamsburg, VA 23185, USA (c) Department of Biology, Mudd Hall 305, The Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218, USA Article History: Received 6 May 2009; Revised 9 July 2009; Accepted 10 July 2009
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- 2009
8. Live imaging of the Drosophila spermatogonial stem cell niche reveals novel mechanisms regulating germline stem cell output
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Sheng, X. Rebecca, primary and Matunis, Erika, additional
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- 2011
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9. Dedifferentiating Spermatogonia Outcompete Somatic Stem Cells for Niche Occupancy in the Drosophila Testis
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Sheng, X. Rebecca, primary, Brawley, Crista M., additional, and Matunis, Erika L., additional
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- 2009
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10. Identification of five mouse μ-opioid receptor (MOR) gene (Oprm1) splice variants containing a newly identified alternatively spliced exon
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Doyle, Glenn A., primary, Sheng, X. Rebecca, additional, Lin, Sharon S.J., additional, Press, Danielle M., additional, Grice, Dorothy E., additional, Buono, Russell J., additional, Ferraro, Thomas N., additional, and Berrettini, Wade H., additional
- Published
- 2007
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11. Identification and functional significance of polymorphisms in the μ-opioid receptor gene (Oprm) promoter of C57BL/6 and DBA/2 mice
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Doyle, Glenn A., primary, Sheng, X. Rebecca, additional, Schwebel, Candice L., additional, Ferraro, Thomas N., additional, Berrettini, Wade H., additional, and Buono, Russell J., additional
- Published
- 2006
- Full Text
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12. Association study of human leukocyte antigen variants and idiopathic pulmonary fibrosis.
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Guillen-Guio B, Paynton ML, Allen RJ, Chin DPW, Donoghue LJ, Stockwell A, Leavy OC, Hernandez-Beeftink T, Reynolds C, Cullinan P, Martinez F, Booth HL, Fahy WA, Hall IP, Hart SP, Hill MR, Hirani N, Hubbard RB, McAnulty RJ, Millar AB, Navaratnam V, Oballa E, Parfrey H, Saini G, Sayers I, Tobin MD, Whyte MKB, Adegunsoye A, Kaminski N, Ma SF, Strek ME, Zhang Y, Fingerlin TE, Molina-Molina M, Neighbors M, Sheng XR, Oldham JM, Maher TM, Molyneaux PL, Flores C, Noth I, Schwartz DA, Yaspan BL, Jenkins RG, Wain LV, and Hollox EJ
- Abstract
Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF, and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Owing to the important role that the human leukocyte antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk., Methods: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising 5159 cases and 27 459 controls, including a prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold of p<4.5×10
-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report., Results: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies., Conclusion: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF., Competing Interests: Conflict of interest: L.J. Donoghue, A. Stockwell, M. Neighbours, X.R. Sheng and B.L. Yaspan are full-time employees of Genentech; A. Stockwell, M. Neighbours, X.R. Sheng and B.L. Yaspan hold stock options in Roche. J.M. Oldham reports personal fees from Boehringer Ingelheim, Genentech, United Therapeutics, AmMax Bio and Lupin Pharmaceuticals outside the submitted work. D.A. Schwartz is the founder and chief scientific officer of Eleven P15, a company focused on the early detection and treatment of pulmonary fibrosis. R.G. Jenkins reports honoraria from Chiesi, Roche, PatientMPower, AstraZeneca, GlaxoSmithKline and Boehringer Ingelheim, and consulting fees from Bristol Myers Squibb, Daewoong, Veracyte, Resolution Therapeutics, RedX, Pliant and Chiesi. L.V. Wain reports research funding from GlaxoSmithKline, Roche and Orion Pharma, and consultancy for GlaxoSmithKline and Galapagos, outside of the submitted work. S.P. Hart and P.L. Molyneaux are associate editors of this journal. The other authors declare no competing interests., (Copyright ©The authors 2024.)- Published
- 2024
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13. Genome-wide SNP-sex interaction analysis of susceptibility to idiopathic pulmonary fibrosis.
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Leavy OC, Goemans AF, Stockwell AD, Allen RJ, Guillen-Guio B, Hernandez-Beeftink T, Adegunsoye A, Booth HL, Cullinan P, Fahy WA, Fingerlin TE, Virk HS, Hall IP, Hart SP, Hill MR, Hirani N, Hubbard RB, Kaminski N, Ma SF, McAnulty RJ, Sheng XR, Millar AB, Molina-Molina M, Navaratnam V, Neighbors M, Parfrey H, Saini G, Sayers I, Strek ME, Tobin MD, Whyte MK, Zhang Y, Maher TM, Molyneaux PL, Oldham JM, Yaspan BL, Flores C, Martinez F, Reynolds CJ, Schwartz DA, Noth I, Jenkins RG, and Wain LV
- Abstract
Background: Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition that is more prevalent in males than females. The reasons for this are not fully understood, with differing environmental exposures due to historically sex-biased occupations, or diagnostic bias, being possible explanations. To date, over 20 independent genetic variants have been identified to be associated with IPF susceptibility, but these have been discovered when combining males and females. Our aim was to test for the presence of sex-specific associations with IPF susceptibility and assess whether there is a need to consider sex-specific effects when evaluating genetic risk in clinical prediction models for IPF., Methods: We performed genome-wide single nucleotide polymorphism (SNP)-by-sex interaction studies of IPF risk in six independent IPF case-control studies and combined them using inverse-variance weighted fixed effect meta-analysis. In total, 4,561 cases (1,280 females and 2,281 males) and 23,500 controls (8,360 females and 14,528 males) of European genetic ancestry were analysed. We used polygenic risk scores (PRS) to assess differences in genetic risk prediction between males and females., Findings: Three independent genetic association signals were identified. All showed a consistent direction of effect across all individual IPF studies and an opposite direction of effect in IPF susceptibility between females and males. None had been previously identified in IPF susceptibility genome-wide association studies (GWAS). The predictive accuracy of the PRSs were similar between males and females, regardless of whether using combined or sex-specific GWAS results., Interpretation: We prioritised three genetic variants whose effect on IPF risk may be modified by sex, however these require further study. We found no evidence that the predictive accuracy of common SNP-based PRSs varies significantly between males and females., Competing Interests: AA declares funding from NIH (K23HL146942); consulting fees from Genentech, Inogen, Medscape, Abbvie, PatientMpower and Boehringer Ingelheim; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Boehringer Ingelheim. ADS is a full-time employee of Genentech/Roche with stock and stock options in Roche. AFG was a full-time employee of PPD, Part of Thermo Fisher Scientific until June 2023. BGG declares fellowship funding from Wellcome Trust (221680/Z/20/Z). BLY is a full-time employee of Genentech/Roche with stock and stock options in Roche. CF declares funding Ministerio de Ciencia e Innovación, Instituto de Salud Carlos III and Instituto Tecnológico y de Energías Renovables; honoraria in educational events from Fundación Instituto Roche. DAS declares being the founder and chief scientific officer of Eleven P15, Inc., a company dedicated to the early diagnosis and treatment of pulmonary fibrosis. HP declares grant payment to institution from Boehringer Ingelheim Ltd; consulting fees from Boehringer Ingelheim Ltd, Roche Limited, Trevi Therapeutics, Pilant Therapeutics; speaker fees from Boehringer Ingelheim Ltd; member of TIPAL trial management group, trustee for Action for Pulmonary Fibrosis, member of scientific advisory board for European Pulmonary Fibrosis Federation. IN declares funding from National Institutes of Health (UG3HL145266) to institution; grant funding to institution from Veracyte; consulting fees from Boerhinger Ingelheim and Sanofi. IPH declares funding from Wellcome Trust and NIHR; vice chair Trustees for Asthma + Lung UK. JMO declares funding from National Institutes of Health (R01HL169166 & K23HL138190); consulting fees from Boehringer Ingelheim, Lupin pharmaceuticals, AmMax Bio, Roche and Veracyte; patent for TOLLIP TT genotype for NAC use in IPF; participation on a Data Safety Monitoring Board or Advisory Board for Endeavor Biomedicines, Novartis and Genentech; Associate editor for CHEST, on Program Committee for American Thoracic Society and Editorial board for AJRCCM. LVW declares funding from UK Research and Innovation (MR/V00235X/1) and GSK/Asthma + Lung UK (Professorship (C17-1)) to complete this work; funding from Orion Pharma, GSK, Genentech, AstraZeneca, Nordic Bioscience, Sysmex (OGT); Consulting fees Galapagos, Boehringer Ingelheim, GSK; support for attending meetings and/or travel Genentech; participation on Advisory Board for Galapagos; leadership or fiduciary roles as Associate Editor for European Respiratory Journal and Medical Research Council Board member and Deputy Chair. MKBW declares funding from National Institutes of Health (K23HL146942); consulting fees from Genentech, Inogen, Medscape, Abbvie, PatientMpower and Boehringer Ingelheim; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Boehringer Ingelheim. MN is a full-time employee of Genentech/Roche with stock and stock options in Roche. NK declares grant funding from National Institutes of Health; grant funding to institution from BMS, Boehringer Ingelheim and Three Lakes Foundation; consultancy fees from Biogen Idec, Boehringer Ingelheim, Third Rock, Pliant, Samumed, NuMedii, Theravance, Three Lake Partners, Astra Zeneca, RohBar, Veracyte, Augmanity, CSL Behring, Thyron, Gilead, Galapagos, Chiesi, Arrowhead, Sofinnova, GSK and Merk; patent for new therapies for IPF (Biotech), new therapies for ARDS (Biotech) and new Biomarkers in IPF (Biotech); equity in Pilant and Thyron; reports serving as the scientific founder of Thyron. PLM declares grant funding to institution from AstraZeneca; consultancy fees from Hoffman-La Roche, Boehringer Ingelheim, AstraZeneca, Trevi and Qureight; speaker fees from Boehringer Ingelheim and Hoffman-La Roche. RGJ declares funding from UK Research and Innovation (MR/V00235X/1); that their institute received funding from Astra Zeneca, Biogen, Galecto, GlaxoSmithKline, Nordic Biosciences, RedX and Pliant; consulting fees from AstraZeneca, Brainomix, Bristol Myers Squibb, Chiesi, Cohbar, Daewoong, GlaxoSmithKline, Veracyte, Resolution Therapeutics and Pliant; payment for lectures and presentations received from Boehringer Ingelheim, Chiesi, Roche, PatientMPower, AstraZeneca; payment for expert testimony from Pinsent Masons LLP; participation on a Data Safety Monitoring Board or Advisory Board for Boehringer Ingelheim, Galapagos, Vicore; leadership or fiduciary role for NuMedii and president for Action for Pulmonary Fibrosis. SPH declares grant funding to institution from Boehringer Ingelheim; consulting fees from Trevi therapeutics; payment or honoraria for lectures, presentations, speakers bureaus, manuscript writing or educational events from Chiesi and Trevi therapeutics; support for attending meetings and/or travel from Chiesi; Participation on a Data Safety Monitoring Board or Advisory Board for Trevi therapeutics; Chair for BTS Standards of Care Committee (till November 2022) and Trustee for Action for Pulmonary Fibrosis. TMM declares consulting fees from Boehringer Ingelheim, Roche/Genentech, Astra Zeneca, Bayer, Blade Therapeutics, Bristol-Myers Squibb, CSL Behring, Galapagos, Galecto, GlaxoSmithKline, IQVIA, Pfizer, Pliant, Respivant, Sanofi, Theravance, Trevi, Veracyte and Vicore; participation on a Data Safety Monitoring Board or Advisory Board for Fibrogen, Blade Therapeutics and Nerre. XRS is a full-time employee of Genentech/Roche with stock and stock options in Roche.
- Published
- 2024
- Full Text
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14. Association study of human leukocyte antigen (HLA) variants and idiopathic pulmonary fibrosis.
- Author
-
Guillen-Guio B, Paynton ML, Allen RJ, Chin DPW, Donoghue LJ, Stockwell A, Leavy OC, Hernandez-Beeftink T, Reynolds C, Cullinan P, Martinez F, Booth HL, Fahy WA, Hall IP, Hart SP, Hill MR, Hirani N, Hubbard RB, McAnulty RJ, Millar AB, Navaratnam V, Oballa E, Parfrey H, Saini G, Sayers I, Tobin MD, Whyte MKB, Adegunsoye A, Kaminski N, Shwu-Fan M, Strek ME, Zhang Y, Fingerlin TE, Molina-Molina M, Neighbors M, Sheng XR, Oldham JM, Maher TM, Molyneaux PL, Flores C, Noth I, Schwartz DA, Yaspan BL, Jenkins RG, Wain LV, and Hollox EJ
- Abstract
Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF and a prior association of the HLA-DQB1 gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Due to the important role that the Human Leukocyte Antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk., Methods: We performed a meta-analysis of associations of the HLA region with IPF risk in individuals of European ancestry from seven independent case-control studies of IPF (comprising a total of 5,159 cases and 27,459 controls, including the prior study of fibrotic interstitial pneumonia). Single nucleotide polymorphisms, classical HLA alleles and amino acids were analysed and signals meeting a region-wide association threshold p <4.5×10
-4 and a posterior probability of replication >90% were considered significant. We sought to replicate the previously reported HLA-DQB1 association in the subset of studies independent of the original report., Results: The meta-analysis of all seven studies identified four significant independent single nucleotide polymorphisms associated with IPF risk. However, none met the posterior probability for replication criterion. The HLA-DQB1 association was not replicated in the independent IPF studies., Conclusion: Variation in the HLA region was not consistently associated with risk in studies of IPF. However, this does not preclude the possibility that other genomic regions linked to the immune response may be involved in the aetiology of IPF., Competing Interests: COMPETING INTERESTS LJD, AS, MN, XRS and BLY are full-time employees of Genentech; AS, MN, XRS, and BLY and hold stock options in Roche. JMO reports personal fees from Boehringer Ingelheim, Genentech, United Therapeutics, AmMax Bio and Lupin Pharmaceuticals outside of the submitted work. DAS is the founder and chief scientific officer of Eleven P15, a company focused on the early detection and treatment of pulmonary fibrosis. RGJ reports honoraria from Chiesi, Roche, PatientMPower, AstraZeneca, GSK, Boehringer Ingelheim, and consulting fees from Bristol Myers Squibb, Daewoong, Veracyte, Resolution Therapeutics, RedX, Pliant, Chiesi. LVW reports research funding from GlaxoSmithKline, Roche and Orion Pharma, and consultancy for GlaxoSmithKline and Galapagos, outside of the submitted work. The other authors declare no competing interests.- Published
- 2023
- Full Text
- View/download PDF
15. Live imaging of the Drosophila spermatogonial stem cell niche reveals novel mechanisms regulating germline stem cell output.
- Author
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Sheng XR and Matunis E
- Subjects
- Animals, Cell Differentiation, Cell Lineage, Cell Survival, Male, Testis cytology, Drosophila melanogaster cytology, Microscopy, Confocal methods, Spermatogonia cytology, Stem Cell Niche cytology, Stem Cells cytology
- Abstract
Adult stem cells modulate their output by varying between symmetric and asymmetric divisions, but have rarely been observed in living intact tissues. Germline stem cells (GSCs) in the Drosophila testis are anchored to somatic hub cells and were thought to exclusively undergo oriented asymmetric divisions, producing one stem cell that remains hub-anchored and one daughter cell displaced out of the stem cell-maintaining micro-environment (niche). We developed extended live imaging of the Drosophila testis niche, allowing us to track individual germline cells. Surprisingly, new wild-type GSCs are generated in the niche during steady-state tissue maintenance by a previously undetected event we term 'symmetric renewal', where interconnected GSC-daughter cell pairs swivel such that both cells contact the hub. We also captured GSCs undergoing direct differentiation by detaching from the hub. Following starvation-induced GSC loss, GSC numbers are restored by symmetric renewals. Furthermore, upon more severe (genetically induced) GSC loss, both symmetric renewal and de-differentiation (where interconnected spermatogonia fragment into pairs while moving towards then establishing contact with the hub) occur simultaneously to replenish the GSC pool. Thus, stereotypically oriented stem cell divisions are not always correlated with an asymmetric outcome in cell fate, and changes in stem cell output are governed by altered signals in response to tissue requirements.
- Published
- 2011
- Full Text
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16. Make room for dedifferentiation.
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Sheng XR and Matunis EL
- Subjects
- Animals, Drosophila Proteins metabolism, Male, Spermatogonia cytology, Cell Dedifferentiation physiology, Cell Movement physiology, Drosophila physiology, Models, Biological, STAT Transcription Factors metabolism, Signal Transduction physiology, Stem Cells cytology
- Abstract
The reversal of cellular differentiation, or dedifferentiation, has fascinated biologists for many decades. While cells can be re-programmed extensively in culture, examples of in vivo dedifferentiation have recently emerged in both vertebrate and invertebrate systems, allowing for analysis of this intriguing process under more physiologically relevant conditions. Studies suggest that dedifferentiation occurs not only during large-scale cellular regeneration, but also at low levels to replenish stem cells lost due to normal turnover. Our recent paper demonstrates a novel method to induce the dedifferentiation of lineage-committed stem cell daughters back into germline stem cells (GSCs) in the Drosophila testis. We also show a requirement for activation of Janus kinase-signal transducer and activator of transcription (Jak-STAT) signaling in this process, and suggest that normally non-motile germline cells gain mobility and out-compete resident somatic cells for occupancy in the stem cell-maintaining microenvironment (niche). Here, we discuss what our findings reveal about stem cell competition and the capacity of various cell types to dedifferentiate.
- Published
- 2009
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17. Identification of five mouse mu-opioid receptor (MOR) gene (Oprm1) splice variants containing a newly identified alternatively spliced exon.
- Author
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Doyle GA, Sheng XR, Lin SS, Press DM, Grice DE, Buono RJ, Ferraro TN, and Berrettini WH
- Subjects
- 3' Untranslated Regions, Amino Acid Sequence, Animals, Base Sequence, Brain metabolism, Cloning, Molecular, DNA Primers genetics, DNA, Complementary genetics, Exons, Genetic Variation, Introns, Male, Mice, Mice, Inbred C57BL, Mice, Inbred DBA, Molecular Sequence Data, Protein Biosynthesis, RNA, Messenger genetics, RNA, Messenger metabolism, Sequence Homology, Amino Acid, Sequence Homology, Nucleic Acid, Alternative Splicing, Receptors, Opioid, mu genetics
- Abstract
The mouse mu-opioid receptor gene, Oprm1, currently contains 18 recognized alternatively spliced exons [Doyle, G.A., Sheng, X.R., Lin, S.S.J., Press, D.M., Grice, D.E., Buono, R.J., Ferraro, T.N., Berrettini, W.H., 2007. Identification of three mouse mu-opioid receptor (MOR) gene (Oprm1) splice variants containing a newly identified alternatively spliced exon. Gene 388 (1-2) 135-147, in press (doi:10.1016/j.gene.2006.10.017). Electronic publication 2006 November 1] that generate 27 splice variants encoding at least 11 morphine-binding isoforms of the receptor. Here, we identify five MOR variants that contain an as yet undescribed exon (exon 19) of the gene, and we provide evidence that these MOR splice variants are expressed in the C57BL/6 and DBA/2 mouse strains. Three splice variants, MOR-1Eii, MOR-1Eiii and MOR-1Eiv, encode the MOR-1E isoform and contain the newly identified exon 19 in their 3' untranslated regions. The fourth splice variant encodes a novel mu-opioid receptor isoform, MOR-1U, and contains exon 19 in its coding region. The cytoplasmic tail of the putative MOR-1U isoform contains a putative nuclear localization signal encoded by the sequence of exon 19. Exon 19 appears to be conserved in the rat, but not in humans. In mouse and rat Oprm1, exon 19 is located between described exons 7 and 8. We also report the cloning of the "full-length" MOR-1T splice variant [Kvam, T.-M., Baar, C., Rakvag, T.T., Kaasa, S., Krokan, H.E., Skorpen, F., 2004. Genetic analysis of the murine mu-opioid receptor: increased complexity of Oprm1 gene splicing, J. Mol. Med. 82 (4) 250-255] that encodes MOR-1 and contains the newly identified exon in its 3' UTR. RT-PCR analysis suggests that splice variants MOR-1Eii, MOR-1Eiii, MOR-1Eiv, MOR-1T and MOR-1U are expressed in all brain regions analyzed (cortex, cerebellum, hypothalamus, thalamus and striatum). These exon 19-containing splice variants add to the growing complexity of the mouse Oprm1 gene.
- Published
- 2007
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18. Identification and functional significance of polymorphisms in the mu-opioid receptor gene (Oprm) promoter of C57BL/6 and DBA/2 mice.
- Author
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Doyle GA, Sheng XR, Schwebel CL, Ferraro TN, Berrettini WH, and Buono RJ
- Subjects
- Animals, Brain drug effects, Brain metabolism, Brain physiopathology, Brain Chemistry drug effects, Brain Chemistry genetics, Cell Line, Tumor, Disease Models, Animal, Gene Expression Regulation drug effects, Gene Expression Regulation genetics, Mice, Mice, Inbred C57BL, Mice, Inbred DBA, Molecular Sequence Data, Morphine pharmacology, Morphine Dependence genetics, Morphine Dependence metabolism, Morphine Dependence physiopathology, Narcotics pharmacology, Neurons drug effects, Neurons metabolism, Sequence Homology, Nucleic Acid, Species Specificity, Genetic Predisposition to Disease genetics, Polymorphism, Single Nucleotide genetics, Promoter Regions, Genetic genetics, Receptors, Opioid, mu genetics
- Abstract
C57BL/6J and DBA/2J mice demonstrate differences in morphine preference when tested in a two-bottle choice paradigm. Quantitative trait loci (QTL) mapping suggested the proximal region of chromosome 10 was responsible for 41% of the observed genetic variance. The mu-opioid receptor (MOR) gene (Oprm) maps to this region and is a prime candidate for explaining the QTL. We hypothesized that variations in Oprm between these strains are responsible for differences in morphine preference. We identify five single nucleotide polymorphisms (SNPs) in the Oprm promoter; three within or near putative transcription factor binding sites. Promoter fragments were amplified from genomic DNA by polymerase chain reaction (PCR) and subcloned into luciferase reporter vectors. A significant difference in basal Oprm promoter activity was seen with C57BL/6 and DBA/2 approximately 1675 constructs in MOR-positive BE(2)-C cells, but not in MOR-negative Neuro-2a cells. In BE(2)-C cells, average DBA/2 approximately 1675 construct activity was 1.3-2.0x greater than average C57BL/6 activity suggesting that the SNPs might alter MOR expression in these two mouse strains. Significant differences in promoter activities between the two cell lines suggest that cell-type-specific transcription factors are involved. No significant differences in construct activity were found between untreated and morphine-treated BE(2)-C or Neuro-2a cells, suggesting that morphine does not regulate transcription of Oprm.
- Published
- 2006
- Full Text
- View/download PDF
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