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Gigantochloa glabrata N. H. Xia & Y. Zeng ex D. Z. Li & Z. C. Xu, sp. nov., a new species of paleotropical woody bamboo has been described and illustrated from Yunnan, China. The new species is morphologically similar to G. albociliata and G. levis, but differs from them by having erect culm sheath blades; culm sheath ligules 4-6 mm high, truncate, denticulate; and with a ring of white tomentum on the intranode and below the node. The new species was mistakenly identified as Gigantochloa albociliata in the Flora of China and was recognised with description of the vegetative characters in 2014, but it was not effectively published. Here, we designate a complete specimen with inflorescence as the type and describe it in accordance with the Code. [ABSTRACT FROM AUTHOR]

Eaf factors play a crucial role in tumor suppression and embryogenesis. To investigate the potential mechanism of Eaf activity, we performed loss- and gain-of-function assays in zebrafish using morpholino and mRNA injections, respectively. We found that eaf1 and eaf2 inhibit Wnt/β-catenin signaling, thereby modulating mesodermal and neural patterning in the embryo. Moreover, ectopic expression of eaf1 and eaf2 in embryos and cultured cells blocked β catenin reporter activity. By immunoprecipitation, we also observed that Eaf1 and Eaf2 bound to the Armadillo repeat region and C-terminus of β-catenin, as well as to other β-catenin transcription complex proteins, such as c-Jun, Tcf and Axin, suggesting the formation of a novel complex. In addition, the N-terminus of Eaf1 and Eaf2 bound to β catenin and exhibited dominant-negative activity, whereas the C-terminus appeared to either harbor a suppression domain or to recruit a repressor. Both the N- and C-terminus must be intact for Eaf1 and Eaf2 suppressive activity. Lastly, we demonstrate a conservation of biological activities for Eaf family proteins across species. In summary, our evidence points to a novel role for Eaf1 and Eaf2 in inhibiting canonical Wnt/β-catenin signaling, which might form the mechanistic basis for Eaf1 and Eaf2 tumor suppressor activity. [ABSTRACT FROM AUTHOR]

FOXO genes are involved in many aspects of development and vascular homeostasis by regulating cell apoptosis, proliferation, and the control of oxidative stress. In addition, FOXO genes have been showed to inhibit Wnt/β-catenin signaling by competing with T cell factor to bind to b-catenin. However, how important of this inhibition in vivo, particularly in embryogenesis is still unknown. To demonstrate the roles of FOXO genes in embryogenesis will help us to further understand their relevant physiological functions. Zebrafish foxo3b gene, an orthologue of mammalian FOXO3, was expressed maternally and distributed ubiquitously during early embryogenesis and later restricted to brain. After morpholino-mediated knockdown of foxo3b, the zebrafish embryos exhibited defects in axis and neuroectoderm formation, suggesting its critical role in early embryogenesis. The embryo-developmental marker gene staining at different stages, phenotype analysis and rescue assays revealed that foxo3b acted its role through negatively regulating both maternal and zygotic Wnt/β-catenin signaling. Moreover, we found that foxo3b could interact with zebrafish β-catenin1 and β-catenin2 to suppress their transactivation in vitro and in vivo, further confirming its role relevant to the inhibition of Wnt/β-catenin signaling. Taken together, we revealed that foxo3b played a very important role in embryogenesis and negatively regulated maternal and zygotic Wnt/β-catenin signaling by directly interacting with both b-catenin1 and b-catenin2. Our studies provide an in vivo model for illustrating function of FOXO transcription factors in embryogenesis. [ABSTRACT FROM AUTHOR]

Studies have attributed several functions to the Eaf family, including tumor suppression and eye development. Given the potential association between cancer and development, we set forth to explore Eafi and Eaf2/u19 activity in vertebrate embryogenesis, using zebrafIsh. In situ hybridization revealed similar eafi and eaf2/u19 expression patterns. Morpholino-mediated knockdown of either eafi or eaf2/u19 expression produced similar morphological changes that could be reversed by ectopic expression of target or reciprocal-target mRNA. However, combination of Eafi and Eaf2/u19 (Eafs)-morpholinos increased the severity of defects, suggesting that Eafi and Eaf2/u19 only share some functional redundancy. The Eafs knockdown phenotype resembled that of embryos with defects in convergence and extension movements. Indeed, knockdown caused expression pattern changes for convergence and extension movement markers, whereas cell tracing experiments using kaeda mRNA showed a correlation between Eafs knockdown and cell migration defects. Cardiac and pancreatic differentiation markers revealed that Eafs knockdown also disrupted midline convergence of heart and pancreatic organ precursors. Noncanonical Wnt signaling plays a key role in both convergence and extension movements and midline convergence of organ precursors. We found that Eafi and Eaf2/u19 maintained expression levels of wnt11 and wn15. Moreover, wntll or wnt5 mRNA partially rescued the convergence and extension movement defects occurring in eafs morphants. Wntll and Wnt5 converge on rhoA, so not surprisingly, rhoA mRNA more effectively rescued defects than either wntll or wnt5 mRNA alone. However, the ectopic expression of wnt11 and wn15 did not affect eaf1 and eaf2/u19 expression. These data indicate that eaf1 and eaf2/u19 act upstream of noncanonical Wnt signaling to mediate convergence and extension movements. [ABSTRACT FROM AUTHOR]

This comparative study of myonuclear domain (MND) size in mammalian species representing a 100 000-fold difference in body mass, ranging from 25 g to 2500 kg, was undertaken to improve our understanding of myonuclear organization in skeletal muscle fibres. Myonuclear domain size was calculated from three-dimensional reconstructions in a total of 235 single muscle fibre segments at a fixed sarcomere length. Irrespective of species, the largest MND size was observed in muscle fibres expressing fast myosin heavy chain (MyHC) isoforms, but in the two smallest mammalian species studied (mouse and rat), MND size was not larger in the fast-twitch fibres expressing the IIA MyHC isofom than in the slow-twitch type I fibres. In the larger mammals, the type I fibres always had the smallest average MND size, but contrary to mouse and rat muscles, type IIA fibres had lower mitochondrial enzyme activities than type I fibres. Myonuclear domain size was highly dependent on body mass in the two muscle fibre types expressed in all species, i.e. types I and IIA. Myonuclear domain size increased in muscle fibres expressing both the β/slow (type I; r= 0.84, P < 0.001) and the fast IIA MyHC isoform ( r= 0.90; P < 0.001). Thus, MND size scales with body size and is highly dependent on muscle fibre type, independent of species. However, myosin isoform expression is not the sole protein determining MND size, and other protein systems, such as mitochondrial proteins, may be equally or more important determinants of MND size. [ABSTRACT FROM AUTHOR]

Abstract   Fetuin-B has recently been cloned and identified from rats, mice, and humans; their expression patterns, however, have not been elucidated yet. In this study, Cagfetuin-B has been cloned in gibel carp. RT-PCR and Western blot detection revealed that Cagfetuin-B is first transcribed from the blastula stage and at a relatively stable level afterward during embryogenesis and the larval stage. Cagfetuin-B transcripts are predominantly distributed over the yolk syncytial layer in the early embryos and later restricted to the cells of liver and brain in newly hatched larvae. Moreover, a dynamic distribution of Cagfetuin-B protein was observed in brain, kidney, liver, and skin during morphogenesis. In adult fish, Cagfetuin-B transcripts are restricted in liver and ovary. Our work, for the first time, revealed the extra-hepatic transcription and a dynamic distribution of fetuin-B during embryogenesis and in adults, which indicates the potential roles of fetuin-B in fish organogenesis. [ABSTRACT FROM AUTHOR]

The sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) is a membrane protein that plays a crucial role in muscle relaxation by transporting cytosolic Ca2+ into the lumen of the sarco/endoplasmic reticulum. In this study, the presence of SERCA1 and SERCA2 was investigated in human intrafusal fibers by immunocytochemistry. Nuclear bag1 fibers contained both SERCA1 and SERCA2 isoforms, with predominant staining seen with SERCA2 in the A and B regions. Most nuclear bag2 fibers also contained SERCA1 and SERCA2 isoforms and their coexistence frequently occurred in the A region. SERCA1 was present whereas SERCA2 was generally absent in the nuclear chain fibers. The staining intensity seen with the SERCA1 monoclonal antibody varied in the order of chain>bag1>bag2. The expression of SERCA1 isoform was found to correlate with the presence of fast myosin heavy chain (MyHC) isoform in nuclear chain fibers, whereas for nuclear bag fibers there was no such apparent correlation between patterns of expression of SERCA and MyHC isoforms. The phenotype revealed for the human bag fibers was very sophisticated and adapted to attain a very wide range of contraction and relaxation velocities. [ABSTRACT FROM AUTHOR]

Generation of hematopoietic stemand progenitor cells (HSPCs) ex vivo and in vivo, especially the generation of safe therapeutic HSPCs, still remains inefficient. In this study, we have identified compound BF170 hydrochloride as a previously unreported pro-hematopoiesis molecule, using the differentiation assays of primary zebrafish blastomere cell culture and mouse embryoid bodies (EBs), and we demonstrate that BF170 hydrochloride promoted definitive hematopoiesis in vivo. During zebrafish definitive hematopoiesis, BF170 hydrochloride increases blood flow, expands hemogenic endothelium (HE) cells and promotes HSPC emergence. Mechanistically, the primary cilia-Ca2+-Notch/NO signaling pathway, which is downstream of the blood flow, mediated the effects of BF170 hydrochloride on HSPC induction in vivo. Our findings, for the first time, reveal that BF170 hydrochloride is a compound that enhances HSPC induction and may be applied to the ex vivo expansion of HSPCs. [ABSTRACT FROM AUTHOR]

Generation of hematopoietic stemand progenitor cells (HSPCs) ex vivo and in vivo, especially the generation of safe therapeutic HSPCs, still remains inefficient. In this study, we have identified compound BF170 hydrochloride as a previously unreported pro-hematopoiesis molecule, using the differentiation assays of primary zebrafish blastomere cell culture and mouse embryoid bodies (EBs), and we demonstrate that BF170 hydrochloride promoted definitive hematopoiesis in vivo. During zebrafish definitive hematopoiesis, BF170 hydrochloride increases blood flow, expands hemogenic endothelium (HE) cells and promotes HSPC emergence. Mechanistically, the primary cilia-Ca2+-Notch/NO signaling pathway, which is downstream of the blood flow, mediated the effects of BF170 hydrochloride on HSPC induction in vivo. Our findings, for the first time, reveal that BF170 hydrochloride is a compound that enhances HSPC induction and may be applied to the ex vivo expansion of HSPCs. [ABSTRACT FROM AUTHOR]

As a copper (Cu) transport ATPase, ATP7A plays an important role in maintaining Cu homeostasis in the body, but the developmental and physiological roles of atp7a in zebrafish embryogenesis are rarely studied. In this study, normal morphological phenotypes of atp7a-/- homozygous zebrafish were observed at both embryonic and adult stages, however, atp7a-/- larvae exhibited delayed touch response and obvious transcriptome changes. Compared with the WT (wild type), differentially expressed genes (DEGs) in atp7a-/- larvae showed the enrichment in gene ontology (GO) terms related to several processes including ATPase activity, oxidoreductase activity, active transmembrane transporter activity, ion binding, and the citrate cycle. Furthermore, decreases in both ATP content and Naþ/Kþ-ATPase activity in atp7a-/- embryos and larvae were unveiled. 57 overlapping DEGs were found both in WT stressed with Cu and in WT mutated with atp7a, and GO term analysis indicated the enrichment in the genes related to neurexin family protein binding and neuronal cell-cell adhesion. Moreover, 42 overlapping DEGs in Cu stressed WT and Cu stressed atp7a-/- were identified. GO term analysis showed an enrichment in the genes related to heme binding, implying that Cu was independent of the integral function of atp7a to affect heme binding. In addition, genes involved in the negative regulation of angiogenesis were down-regulated in atp7a-/- mutants with and without Cu stress, which failed to occur in WT, implying that the integral function of atp7a is required for maintaining the normal expression of angiogenesis genes. The integrative data in this study demonstrated that atp7a is required for ion transport and angiogenesis, and for Cu-induced neurexin family protein binding defects, rather than for Cu-induced heme binding defects, during zebrafish embryogenesis. These findings provide possible clues for human diseases with ATP7A dysfunction and imbalanced Cu homeostasis. [ABSTRACT FROM AUTHOR]

Unbalanced copper (Cu2+) homeostasis is associated with the developmental defects of vertebrate myogenesis, but the underlying molecular mechanisms remain elusive. In this study, it was found that Cu2+ stressed zebrafish embryos and larvae showed reduced locomotor speed as well as loose and decreased myofibrils in skeletal muscle, coupled with the downregulated expression of muscle fiber markers mylpfa and smyhc1l and the irregular arrangement of myofibril and sarcomere. Meanwhile, the Cu2+ stressed zebrafish embryos and larvae also showed significant reduction in the expression of H3K4 methyltransferase smyd1b transcripts and H3K4me3 protein as well as in the binding enrichment of H3K4me3 on gene mylpfa promoter in skeletal muscle cells, suggesting that smyd1b--H3K4me3 axis mediates the Cu2+-induced myofibrils specification defects. Additionally, whole genome DNA methylation sequencing unveiled that the gene smyd5 exhibited significant promoter hyper-methylation and increased expression in Cu2+ stressed embryos, and the ectopic expression of smyd5 in zebrafish embryos also induced the myofibrils specification defects as those observed in Cu2+ stressed embryos. Moreover, Cu2+ was shown to suppress myofibrils specification and smyd1b promoter transcriptional activity directly independent of the integral function of copper transporter cox17 and atp7b. All these data may shed light on the linkage of unbalanced copper homeostasis with specific gene promoter methylation and epigenetic histone protein modification as well as the resultant signaling transduction and the myofibrillogenesis defects. [ABSTRACT FROM AUTHOR]

The developmental process of epithelial-mesenchymal transition (EMT) occurs when epithelial cells acquire invasive mesenchymal cell characteristics, and the activation of this process has been indicated to be involved in tumor progression. EMT could be induced by growth factors, cytokines and matrix metalloproteinases (MMPs). sphingosine-1-phosphate (S1P) is a biologically-active lipid that plays an important role in cancer metastasis. S1P also contributes to the activation of EMT. However, the mechanism underlying S1P-induced EMT is unclear. Increased evidence has demonstrated that the cell surface glycocalyx is closed associated with S1P and plays an important role in tumor progression, suggesting that S1P-induced EMT could be Snail-MMP signaling-dependent. Thus, we hypothesize that an S1P-glycocalyx-Snail-MMP signaling axis mediates S1P-induced EMT. This is an essential step towards improved understanding of the underlying mechanism involved in S1P-regulted EMT, and the development of novel diagnostic and anticancer therapeutic strategies. [ABSTRACT FROM AUTHOR]

Copper-induced delayed hatching and dysfunctional movement had been reported previously, and unbalanced free copper was found in the body of humans with Alzheimer's disease and other neural diseases, but details of the underlying mechanisms are still unknown. In this study, zebrafish (Danio rerio) embryos exposed to over 3.9 lM of copper-exhibited delayed hatching and significantly dysfunctional movement. Using high-throughput in situ hybridization screening and by conducting an in-depth analysis of gene characterization in embryos exposed to copper, we found that copper caused neural crest defects from the initiation stage of neurogenesis, and embryos younger than the 70% epiboly stage were sensitive to copper toxicity. The myelination of Schwann cells, other than melanophores, cartilage, and neurons, was inhibited by copper during neurogenesis. In addition, axon guidance was blocked by copper. Downregulated cdx4-hox might have contributed to the neurogenesis-related defects. Moreover, copper inhibited the differentiation of muscle fibers and myotomes but not the specification of muscle progenitors. In summary, our data reveal a novel molecular mechanism for copper-inhibited locomotor behavior in embryos, in which copper blocks functional muscle fiber specification during myogenesis and inhibits the specification of axons and Schwann cell myelination during neurogenesis. A combination of these processes results in dysfunctional locomotor behavior in zebrafish embryos exposed to copper. [ABSTRACT FROM AUTHOR]

Previous studies indicated that EAF (ELL-associated factor) family members, EAF1 and EAF2/U19, play a role in cancer and embryogenesis. For example, EAF2/U19 may serve as a tumor suppressor in prostate cancer. At the same time, EAF2/U19 is a downstream factor in the non-canonical Wnt 4 signaling pathway required for eye development in Xenopus laevis, and along with EAF1, contributes to convergence and extension movements in zebrafish embryos through Wnt maintenance. Here, we used zebrafish embryos and mammalian cells to show that both EAF1 and EAF2/U19 were up-regulated by Wnt4 (Wnt4a). Furthermore, we found that EAF1 and EAF2/U19 suppressed Wnt4 expression by directly binding to the Wnt4 promoter as seen in chromatin immunoprecipitation assays. These findings indicate that an auto-regulatory negative feedback loop occurs between Wnt4 and the EAF family, which is conserved between zebrafish and mammalian. The rescue experiments in zebrafish embryos showed that early embryonic development required the maintenance of the appropriate levels of Wnt4a through the feedback loop. Others have demonstrated that the tumor suppressors p63, p73 and WT1 positively regulate Wnt4 expression while p21 has the opposite effect, suggesting that maintenance of appropriate Wnt4 expression may also be critical for adult tissue homeostasis and prevention against tumor initiation. Thus, the autoregulatory negative feedback loop that controls expression of Wnt4 and EAF proteins may play an important role in both embryonic development and tumor suppression. Our findings provide the first convincing line of evidence that EAF and Wnt4 form an auto-regulatory negative feedback loop in vivo. [ABSTRACT FROM AUTHOR]