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Vascular endothelial growth factor (VEGF) signaling plays a central role in vascular development and maintenance of vascular homeostasis. In endothelial cells (ECs), VEGF activates the gene expression of angiogenic transcription factors (TFs), followed by induction of downstream angiogenic responsive genes. Recent findings support that histone modification dynamics contribute to the transcriptional control of genes that are important for EC functions. Lysine demethylase 2B (KDM2B) demethylates histone H3K4me3 and H3K36me2/3 and mediates the monoubiquitination of histone H2AK119. KDM2B functions as a transcriptional repressor in somatic cell reprogramming and tumor development. However, the role of KDM2B in VEGF signaling remains to be elucidated. Here, we show that KDM2B knockdown enhances VEGF-induced angiogenesis in cultured human ECs via increased migration and proliferation. In contrast, ectopic expression of KDM2B inhibits angiogenesis. The function of KDM2B may depend on its catalytic Jumonji C domain. Genome-wide analysis further reveals that KDM2B selectively controls the transcription of VEGF-induced angiogenic TFs that are associated with increased H3K4me3/H3K36me3 and decreased H2AK119ub. These findings suggest an essential role of KDM2B in VEGF signaling in ECs. As dysregulation of VEGF signaling in ECs is involved in various diseases, including cancer, KDM2B may be a potential therapeutic target in VEGF-mediated vasculopathic diseases. ∙ KDM2B has inhibitory effects on VEGF-induced angiogenesis in endothelial cells. ∙The anti-angiogenic functions of KDM2B is mediated via JmjC domain. ∙KDM2B selectively controls transcription of VEGF-responsive angiogenic TFs. ∙Histone modifications linked to KDM2B are dynamically changed during VEGF-signaling. [ABSTRACT FROM AUTHOR]

Over the last decade, the development and progress of next-generation sequencers incorporated with classical biochemical analyses have drastically produced novel insights into transcription factors, including Sry-like high-mobility group box (SOX) factors. In addition to their primary functions in binding to and activating specific downstream genes, transcription factors also participate in the dedifferentiation or direct reprogramming of somatic cells to undifferentiated cells or specific lineage cells. Since the discovery of SOX factors, members of the SOXF (SOX7, SOX17, and SOX18) family have been identified to play broad roles, especially with regard to cardiovascular development. More recently, SOXF factors have been recognized as crucial players in determining the cell fate and in the regulation of cancer cells. Here, we provide an overview of research on the mechanism by which SOXF factors regulate development and cancer, and discuss their potential as new targets for cancer drugs while offering insight into novel mechanistic transcriptional regulation during cell lineage commitment. [ABSTRACT FROM AUTHOR]

We construct the non-compact Calabi–Yau manifolds interpreted as the complex line bundles over the Hermitian symmetric spaces. These manifolds are the various generalizations of the complex line bundle over CPN−1. Imposing an F-term constraint on the line bundle over CPN−1, we obtain the line bundle over the complex quadric surface QN−2. On the other hand, when we promote the U(1) gauge symmetry in CPN−1 to the non-abelian gauge group U(M), the line bundle over the Grassmann manifold is obtained. We construct the non-compact Calabi–Yau manifolds with isometries of exceptional groups, which we have not discussed in the previous papers. Each of these manifolds contains the resolution parameter which controls the size of the base manifold, and the conical singularity appears when the parameter vanishes. [Copyright &y& Elsevier]

Newborn neurons migrate extensively in the radial and tangential directions to organize the developing vertebrate nervous system. We show here that mutations in zebrafish trilobite (tri) that affect gastrulation-associated cell movements also eliminate tangential migration of motor neurons in the hindbrain. In the wild-type hindbrain, facial (nVII) and glossopharyngeal (nIX) motor neurons are induced in rhombomeres 4 and 6, respectively, and migrate tangentially into r6 and r7 (nVII) and r7 (nIX). In all three tri alleles examined, although normal numbers of motor neurons are induced, nVII motor neurons are found exclusively in r4, and nIX-like motor neurons are found exclusively in r6. The migration of other neuronal and nonneuronal cell types is unaffected in tri mutants. Rhombomere formation and the development of other hindbrain neurons are also unaffected in tri mutants. Furthermore, tangential neuronal migration occurs normally in the gastrulation mutant knypek, indicating that the trilobite neuron phenotype does not arise nonspecifically from aberrant gastrulation-associated movements. We conclude that trilobite function is specifically required for two types of cell migration that occur at different stages of zebrafish development. [Copyright &y& Elsevier]

Abstract: Trm1 catalyzes a two-step reaction, leading to mono- and dimethylation of guanosine at position 26 in most eukaryotic and archaeal tRNAs. We report the crystal structures of Trm1 from Pyrococcus horikoshii liganded with S-adenosyl-l-methionine or S-adenosyl-l-homocysteine. The protein comprises N-terminal and C-terminal domains with class I methyltransferase and novel folds, respectively. The methyl moiety of S-adenosyl-l-methionine points toward the invariant Phe27 and Phe140 within a narrow pocket, where the target G26 might flip in. Mutagenesis of Phe27 or Phe140 to alanine abolished the enzyme activity, indicating their role in methylating G26. Structural analyses revealed that the movements of Phe140 and the loop preceding Phe27 may be involved in dissociation of the monomethylated tRNA•Trm1 complex prior to the second methylation. Moreover, the catalytic residues Asp138, Pro139, and Phe140 are in a different motif from that in DNA 6-methyladenosine methyltransferases, suggesting a different methyl transfer mechanism in the Trm1 family. [Copyright &y& Elsevier]

Intestinal ischemia and enterocyte injury are significant causes of death after cardiac surgery. Hemodialysis is a well-known risk factor for intestinal ischemia. However, the relationship between enterocyte injury and mortality is unclear. This exploratory study assessed the association between intestinal fatty acid–binding protein (I-FABP), a specific marker of enterocyte injury, at intensive care unit (ICU) admission and in-hospital mortality in patients on hemodialysis who underwent cardiac surgery with cardiopulmonary bypass. Forty-seven consecutive patients on long-term hemodialysis who underwent elective cardiac surgery (median age, 70 y; men, 27 [57%]) were prospectively enrolled. The association between serum I-FABP levels at ICU admission and in-hospital mortality was compared with the associations between serum I-FABP levels and prognostic severity scores, vasoactive-inotropic scores, and lactate levels. Only I-FABP levels at ICU admission were significantly related to in-hospital mortality (odds ratio, 5.54; 95% confidence interval [CI], 1.08-28.43) in the simple logistic regression analysis. Univariate and multiple linear regression analyses indicated prolonged cardiopulmonary bypass (ρ, 0.49; 95% CI, 0.15-0.83), higher mean norepinephrine dose (ρ, 0.07; 95% CI, 0.02-0.12), lower mean dopamine dose (ρ, −0.51; 95% CI, −0.94 to −0.08), and intra-aortic balloon pump use (ρ, 3.63; 95% CI, 1.68-5.59) were significant risk factors for high I-FABP levels. Enterocyte injury at ICU admission was associated with in-hospital mortality after cardiac surgery for patients on hemodialysis. Intraoperative hidden hypoperfusion of the intestine may impact prognoses. Enterocyte injury prevention, early diagnosis, and intervention for intestinal ischemia might be required to improve outcomes. [ABSTRACT FROM AUTHOR]

In vertebrates, the periodic formation of somites from the presomitic mesoderm (PSM) is driven by the molecular oscillator known as the segmentation clock. The hairy -related gene, hes6/her13.2, functions as a hub by dimerizing with other oscillators of the segmentation clock in zebrafish embryos. Although hes6 exhibits a posterior–anterior expression gradient in the posterior PSM with a peak at the tailbud, the detailed mechanisms underlying this unique expression pattern have not yet been clarified. By establishing several transgenic lines, we found that the transcriptional regulatory region downstream of hes6 in combination with the hes6 3′UTR recapitulates the endogenous gradient of hes6 mRNA expression. This downstream region, which we termed the PT enhancer, possessed several putative binding sites for the T-box and Ets transcription factors that were required for the regulatory activity. Indeed, the T-box transcription factor (Tbx16) and Ets transcription factor (Pea3) bound specifically to the putative binding sites and regulated the enhancer activity in zebrafish embryos. In addition, the 3′UTR of hes6 is required for recapitulation of the endogenous mRNA expression. Furthermore, the PT enhancer with the 3′UTR of hes6 responded to the inhibition of retinoic acid synthesis and fibroblast growth factor signaling in a manner similar to endogenous hes6 . The results showed that transcriptional regulation by the T-box and Ets transcription factors, combined with the mRNA stability given by the 3′UTR, is responsible for the unique expression gradient of hes6 mRNA in the posterior PSM of zebrafish embryos. [ABSTRACT FROM AUTHOR]

Abstract: The broad diversity of neurons is vital to neuronal functions. During vertebrate development, the spinal cord is a site of sensory and motor tasks coordinated by interneurons and the ongoing neurogenesis. In the spinal cord, V2-interneuron (V2-IN) progenitors (p2) develop into excitatory V2a-INs and inhibitory V2b-INs. The balance of these two types of interneurons requires precise control in the number and timing of their production. Here, using zebrafish embryos with altered Notch signaling, we show that different combinations of Notch ligands and receptors regulate two functions: the maintenance of p2 progenitor cells and the V2a/V2b cell fate decision in V2-IN development. Two ligands, DeltaA and DeltaD, and three receptors, Notch1a, Notch1b, and Notch3 redundantly contribute to p2 progenitor maintenance. On the other hand, DeltaA, DeltaC, and Notch1a mainly contribute to the V2a/V2b cell fate determination. A ubiquitin ligase Mib, which activates Notch ligands, acts in both functions through its activation of DeltaA, DeltaC, and DeltaD. Moreover, p2 progenitor maintenance and V2a/V2b fate determination are not distinct temporal processes, but occur within the same time frame during development. In conclusion, V2-IN cell progenitor proliferation and V2a/V2b cell fate determination involve signaling through different sets of Notch ligand–receptor combinations that occur concurrently during development in zebrafish. [Copyright &y& Elsevier]

Abstract: Objective: This study aimed to identify a set of endometrioid endometrial carcinoma EEC-associated microRNAs (miRNAs) in tissue and plasma, and evaluate their clinical significance. Methods: A set of EEC-associated miRNAs in tissue and plasma was identified by next-generation sequencing (NGS), which could enable in-depth characterization of the global repertoire of miRNAs. Results: NGS identified 11 candidate EEC-associated miRNAs. Quantitative reverse-transcriptase PCR identified 8 EEC-associated miRNAs in tissue (upregulated: miR-499, miR-135b, miR-205, downregulated: miR-10b, miR-195, miR-30a-5p, miR-30a-3p and miR-21). Expression of hsa-miR-499 in International Federation of Gynecology and Obstetrics (FIGO) Stage IA and Grade 1 tissues was significantly lower than in others (FIGO Stage IB or more advanced, and Grade 2 or 3). By receiver operating characteristic (ROC) curve analysis, compared with single EEC-associated miRNA, two miRNA signatures (miR135b/miR195 and miR135b/miR30a-3p) could distinguish between EEC and normal endometrial tissue samples yielding a high area under the curve (AUC) of 0.9835 [95% confidence interval (CI): 0.9677–1.0], and 0.9898 (95% CI: 0.9677–1.0), respectively. As possible non-invasive markers for EEC, four EEC-associated miRNAs (increased level: miR-135b and miR-205, decreased-level: miR-30a-3p and miR-21) in plasma were identified. Circulating levels of three EEC-associated miRNAs (miR-135b, miR-205 and miR-30a-3p) in plasma were significantly decreased after hysterectomy. ROC curves analysis revealed that miR-135b and miR-205 levels in plasma yielded AUCs of 0.9722 (95% CI: 0.913–1.0) and 1.0 (95% CI: 1.0–1.0), respectively. Conclusion: Measurement of tissue and plasma EEC-associated miRNAs may be useful for early detection, diagnostic, and follow-up tests for EEC. [Copyright &y& Elsevier]

Abstract: In mammals, cerebellar neurons are categorized as glutamatergic or GABAergic, and are derived from progenitors that express the proneural genes atoh1 or ptf1a, respectively. In zebrafish, three atoh1 genes, atoh1a, atoh1b, and atoh1c, are expressed in overlapping but distinct expression domains in the upper rhombic lip (URL): ptf1a is expressed exclusively in the ventricular zone (VZ). Using transgenic lines expressing fluorescent proteins under the control of the regulatory elements of atoh1a and ptf1a, we traced the lineages of the cerebellar neurons. The atoh1 + progenitors gave rise not only to granule cells but also to neurons of the anteroventral rhombencephalon. The ptf1a + progenitors generated Purkinje cells. The olig2 + eurydendroid cells, which are glutamatergic, were derived mostly from ptf1a + progenitors in the VZ but some originated from the atoh1 + progenitors in the URL. In the adult cerebellum, atoh1a, atoh1b, and atoh1c are expressed in the molecular layer of the valvula cerebelli and of the medial corpus cerebelli, and ptf1a was detected in the VZ. The proneural gene expression patterns coincided with the sites of proliferating neuronal progenitors in the adult cerebellum. Our data indicate that proneural gene-linked neurogenesis is evolutionarily conserved in the cerebellum among vertebrates, and that the continuously generated neurons help remodel neural circuits in the adult zebrafish cerebellum. [Copyright &y& Elsevier]

Abstract: The lateral line system displays highly divergent patterns in adult teleost fish. The mechanisms underlying this variability are poorly understood. Here, we demonstrate that the lateral line mechanoreceptor, the neuromast, gives rise to a series of accessory neuromasts by a serial budding process during postembryonic development in zebrafish. We also show that accessory neuromast formation is highly correlated to the development of underlying dermal structures such as bones and scales. Abnormalities in opercular bone morphogenesis, in endothelin 1-knockdown embryos, are accompanied by stereotypic errors in neuromast budding and positioning, further demonstrating the tight correlation between the patterning of neuromasts and of the underlying dermal bones. In medaka, where scales form between peridermis and opercular bones, the lateral line displays a scale-specific pattern which is never observed in zebrafish. These results strongly suggest a control of postembryonic neuromast patterns by underlying dermal structures. This dermal control may explain some aspects of the evolution of lateral line patterns. [Copyright &y& Elsevier]

Abstract: The cerebellum is important for the integration of sensory perception and motor control, but its structure has mostly been studied in mammals. Here, we describe the cell types and neural tracts of the adult zebrafish cerebellum using molecular markers and transgenic lines. Cerebellar neurons are categorized to two major groups: GABAergic and glutamatergic neurons. The Purkinje cells, which are GABAergic neurons, express parvalbumin7, carbonic anhydrase 8, and aldolase C like (zebrin II). The glutamatergic neurons are vglut1 + granule cells and vglut2 high cells, which receive Purkinje cell inputs; some vglut2 high cells are eurydendroid cells, which are equivalent to the mammalian deep cerebellar nuclei. We found olig2 + neurons in the adult cerebellum and ascertained that at least some of them are eurydendroid cells. We identified markers for climbing and mossy afferent fibers, efferent fibers, and parallel fibers from granule cells. Furthermore, we found that the cerebellum-like structures in the optic tectum and antero-dorsal hindbrain show similar Parvalbumin7 and Vglut1 expression profiles as the cerebellum. The differentiation of GABAergic and glutamatergic neurons begins 3 days post-fertilization (dpf), and layers are first detectable 5 dpf. Using anti-Parvalbumin7 and Vglut1 antibodies to label Purkinje cells and granule cell axons, respectively, we screened for mutations affecting cerebellar neuronal development and the formation of neural tracts. Our data provide a platform for future studies of zebrafish cerebellar development. [Copyright &y& Elsevier]

Abstract: Islet-1 (Isl1) is a member of the Isl1 family of LIM-homeodomain transcription factors (LIM-HD) that is expressed in a defined subset of motor and sensory neurons during vertebrate embryogenesis. To investigate how this specific expression of isl1 is regulated, we searched for enhancers of the isl1 gene that are conserved in vertebrate evolution. Initially, two enhancer elements, CREST1 and CREST2, were identified downstream of the isl1 locus in the genomes of fugu, chick, mouse, and human by BLAST searching for highly similar elements to those originally identified as motor and sensory neuron-specific enhancers in the zebrafish genome. The combined action of these elements is sufficient for completely recapitulating the subtype-specific expression of the isl1 gene in motor neurons of the mouse spinal cord. Furthermore, by direct comparison of the upstream flanking regions of the zebrafish and human isl1 genes, we identified another highly conserved noncoding element, CREST3, and subsequently C3R, a similar element to CREST3 with two CDP CR1 recognition motifs, in the upstream regions of all other isl1 family members. In mouse and human, CRESTs are located as far as more than 300 kb away from the isl1 locus, while they are much closer to the isl1 locus in zebrafish. Although all of zebrafish CREST2, CREST3, and C3R activate gene expression in the sensory neurons of zebrafish, CREST2 of mouse and human does not have the sequence necessary for sensory neuron-specific expression. Our results revealed both a remarkable conservation of the regulatory elements regulating subtype-specific gene expression in motor and sensory neurons and the dynamic process of reorganization of these elements whereby each element increases the level of cell-type specificity by losing redundant functions with the other elements during vertebrate evolution. [Copyright &y& Elsevier]

In vertebrate embryos, spinal motor neurons project through segmentally reiterated nerves into the somites. Here, we report that zebrafish secondary motor neurons, which are similar to motor neurons in birds and mammals, depend on myotomal cues to navigate into the periphery. We show that the absence of myotomal adaxial cells in you-too/gli2 embryos severely impairs secondary motor axonal pathfinding, including their ability to project into the somites. Moreover, in diwanka mutant embryos, in which adaxial cells are present but fail to produce cues essential for primary motor growth cones to pioneer into the somites, secondary motor axons display similar pathfinding defects. The similarities between the axonal defects in you-too/gli2 and diwanka mutant embryos strongly suggest that pathfinding of secondary motor axons depends on myotome-derived cues, and that the diwanka gene is a likely candidate to produce or encode such a cue. Our experiments also demonstrate that diwanka plays a central role in the migration of primary and secondary motor neurons, suggesting that both neural populations share mechanisms underlying axonal pathfinding. In summary, we provide compelling evidence that myotomal cells produce multiple signals to initiate and control the migration of spinal nerve axons into the somites. [Copyright &y& Elsevier]