Gene Expression Patterns最新文献

The mammalian organ of Corti is a highly specialized sensory organ of the cochlea with a fine-grained pattern that is essential for auditory function. The sensory epithelium, the organ of Corti consists of a single row of inner hair cells and three rows of outer hair cells that are intercalated by support cells in a mosaic pattern. Previous studies show that the Wnt pathway regulates proliferation, promotes medial compartment formation in the cochlea, differentiation of the mechanosensory hair cells and axon guidance of Type II afferent neurons. WNT ligand expressions are highly dynamic throughout development but are insufficient to explain the roles of the Wnt pathway. We address a potential way for how WNTs specify the medial compartment by characterizing the expression of Porcupine (PORCN), an O-acyltransferase that is required for WNT secretion. We show PORCN expression across embryonic ages (E)12.5 - E14.5, E16.5, and postnatal day (P)1. Our results showed enriched PORCN in the medial domains during early stages of development, indicating that WNTs have a stronger influence on patterning of the medial compartment. PORCN was rapidly downregulated after E14.5, following the onset of sensory cell differentiation; residual expression remained in some hair cells and supporting cells. On E14.5 and E16.5, we also examined the spatial expression of Gsk3β, an inhibitor of canonical Wnt signaling to determine its potential role in radial patterning of the cochlea. Gsk3β was broadly expressed across the radial axis of the epithelium; therefore, unlikely to control WNT-mediated medial specification. In conclusion, the spatial expression of PORCN enriches WNT secretion from the medial domains of the cochlea to influence the specification of cell fates in the medial sensory domain.

Despite comprising much of the genome, transposons were once thought of as junk. However, transposons play many roles in the eukaryotic genome, such as providing new proteins as domesticated genes, expressing during germline-soma differentiation, function in DNA rearrangement in the offspring, and so on. We sought to describe the distribution and structural organization of the two autonomous transposons (ZB and PS) in the zebrafish genome and examine their expression patterns in embryos and adult tissues. The intact copy of ZB and PS was queried by BLAST on NCBI and ENSEMBL using default parameters. Of the copies with coverage and identity, more than 90 % were downloaded to do structural analysis. Spatial and temporal expression patterns were detected by qRT-PCR and Whole-mount in situ hybridization (WISH). There are 19 intact copies of ZB, encoding 341 amino acid residues with DD34E catalytic domain and flanked by 201bp TIRs, and seven intact PS copies, containing 425 amino acid residues with DD35D catalytic domain flanked by 28bp TIRs, were detected in the genome of zebrafish respectively. Analysis of genomic insertions indicated that both ZB and PS transposons are prone to be retained in the intron and intergenic regions of the zebrafish genome. The sense and antisense transcripts of ZB and PS were detected during embryonic development stages and exhibited similar expression patterns. The difference is that the sense strand transcript of ZB was explicitly expressed in midbrain-hindbrain boundary (MHB) and otic vesicle (OV), and pharyngeal arches and pharyngeal pouches (PA&PP) at 48 hpf. In adult zebrafish, the expressions of ZB and PS in muscle and brain are much higher than in other tissues. Our study results indicate that ZB and PS transposons may be involved in the embryonic development and regulation of somatic cells of certain adult tissues, such as the brain and muscle.

Galloway-Mowat syndrome (GAMOS) is a rare developmental disease. Patients suffer from congenital brain anomalies combined with renal abnormalities often resulting in an early-onset steroid-resistant nephrotic syndrome.

The etiology of GAMOS has a heterogeneous genetic contribution. Mutations in more than 10 different genes have been reported in GAMOS patients. Among these are mutations in four genes encoding members of the human KEOPS (kinase, endopeptidase and other proteins of small size) complex, including OSGEP, TP53RK, TPRKB and LAGE3. Until now, these components have been functionally mainly investigated in bacteria, eukarya and archaea and in humans in the context of the discovery of its role in GAMOS, but the KEOPS complex members’ expression and function during embryogenesis in vertebrates is still unknown.

In this study, in silico analysis showed that both gene localization and the protein sequences of the three core KEOPS complex members Osgep, Tp53rk and Tprkb are highly conserved across different species including Xenopus laevis. In addition, we examined the spatio-temporal expression pattern of osgep, tp53rk and tprkb using RT-PCR and whole mount in situ hybridization approaches during early Xenopus development. We observed that all three genes were expressed during early embryogenesis and enriched in tissues and organs affected in GAMOS. More precisely, KEOPS complex genes are expressed in the pronephros, but also in neural tissue such as the developing brain, eye and cranial cartilage.

These findings suggest that the KEOPS complex plays an important role during vertebrate embryonic development.

Midbrain dopaminergic neurons (mDA) play an important role in controlling the voluntary motor movement, reward, and emotion-based behaviour. Differentiation of mDA neurons from progenitors depends on several secreted proteins, such as sonic hedgehog (SHH). The present study attempted to elucidate the possible role(s) of some SHH signaling components (Ptch1, Gli1, Gli2 and Gli3) in the spatiotemporal development of mDA neurons along the rostrocaudal axis of the midbrain and their possible roles in differentiation and survival of mDA neurons and the significance of using in vitro models for studying the development of mDA neurons. At E12 and E14, only Ptch1 and Gli1 were expressed in ventrolateral midbrain domains. All examined SHH signalling molecules were not detected in mDA area. Whereas, in MN9D cells, many SHH signalling molecules were expressed and co-localized with the dopaminergic marker; tyrosine hydroxylase (TH), and their expression were upregulated with SHH treatment of the MN9D cells. These results suggest that mDA neurons differentiation and survival might be independent of SHH in the late developmental stages (E12-18). Besides, MN9D cell line is not the ideal in vitro model for investigating the differentiation of mDA and hence, the ventral midbrain primary culture might be favored over MN9D line.

Eya1 and other Eya proteins are important regulators of progenitor proliferation, cell differentiation and morphogenesis in all three germ layers. At present, most of our knowledge of Eya1 distribution is based on in situ hybridization for Eya1 mRNA. However, to begin to dissect the mechanisms underlying Eya1 functions, we need a better understanding of the spatiotemporal distribution of Eya1 proteins during embryonic development, their subcellular localization and their levels of expression in various tissues. Here we report the localization of Eya1 protein throughout embryonic development from neural plate stages to tadpole stages of Xenopus laevis using a specific antibody for Xenopus Eya1. Our study confirms the expression of Eya1 protein in cranial placodes, placodally derived sensory primordia (olfactory epithelium, otic vesicle, lateral line primordia) and cranial ganglia, as well as in somites, secondary heart field and pharyngeal endoderm. In addition, we report here a novel expression of Eya1 proteins in scattered epidermal cells in Xenopus. Our findings also reveal that, while being predominantly expressed in nuclei in most expression domains, Eya1 protein is also localized to the cytoplasm, in particular in the early preplacodal ectoderm, some placode-derived ganglia and a subset of epidermal cells. While some cytoplasmic roles of Eya1 have been previously described in other contexts, the functions of cytoplasmic Eya1 in the preplacodal ectoderm, cranial ganglia and epidermal cells remain to be investigated.

The pancreas development depends on complex regulation of several signaling pathways, including the Hedgehog (Hh) signaling via a receptor complex component, Smoothened, which deficiency blocks the Hh signaling. Such a defect in birds and mammals results in an annular pancreas. We showed that in developing zebrafish, the mutation of Smoothened or inhibition of Hh signaling by its antagonist cyclopamine caused developmental defects of internal organs, liver, pancreas, and gut. In particular, the pancreatic primordium was duplicated. The two exocrine pancreatic primordia surround the gut. This phenomenon correlates with a significant reduction of the gut's diameter, causing the annular pancreas phenotype.

The present study was undertaken to study the expression of the developmental important gene transcripts in immature oocytes, mature oocytes, different stages of IVF produced embryos, embryonic stem (ES), cumulus (BCC), fetal fibroblast (BFF), newborn fibroblast (NBF) and adult fibroblast (BAF) cells of buffalo by semi-quantitative RT-PCR. The expression of GLUT1, HSP70.1, POL A Polymerase, GDF9, BMP15, and SURVIVIN transcripts was found in immature oocytes, mature oocytes, 2-cell, 4-cell, 8–16 cell, morula, and the blastocyst. Interestingly, the CX43 expression was found in oocytes, embryos, and other cell types, but it was not detected in the blastocyst. However, the IFNT expression was found in the blastocyst only, but not in other cells. The buffalo ES cells showed the expression of intracellular and cell surface markers (NANOG, OCT4, SOX2, FOXD3, SSEA-3, SSEA-4, TRA-1-60, and TRA-1-81) and alkaline phosphatase activity. Two ES cell lines (S-line and M-line-II) were continued to survive up to 98th passages (~630 days) and 97th passages (~624 days), respectively. It was interesting to note that GLUT1, CX43, HSP70.1, POL A Polymerase, GDF9, BMP15, and SURVIVIN transcripts (except the IFNT) were expressed in buffalo ES, BCC, BFF, NBF and BAF cells. This is the first preliminary report that the buffalo ES, BCC, BFF, NBF, and BAF cells expressed the several developmental important candidate genes. It is concluded that the expression of the major developmental important genes was not only expressed in the oocytes and embryos but also expressed in the ES, BCC, BFF, NBF, and BAF cells of buffalo.

Nanos proteins are essential for developing primordial germ cells (PGCs) in both invertebrates and vertebrates. In invertebrates, also contribute to the patterning of the anterior-posterior axis of the embryo and the neural development. In vertebrates, however, besides the role of Nanos proteins in PGC development, the biological functions of the proteins in normal development have not yet been identified. Here, we analyzed the expression and function of nanos1 during craniofacial development in zebrafish. nanos1 was expressed in the pharyngeal endoderm and endodermal pouches essential for the development of facial skeletons and endocrine glands in the vertebrate head. However, no craniofacial defects, such as abnormal pouches, hypoplasia of the thymus, malformed facial skeletons, have been found in nanos1 knockout animals. The normal craniofacial development of nanos1 knockout animals is unlikely a consequence of the genetic redundancy of Nanos1 with Nanos2 or Nanos3 or a result of the genetic compensation for the loss of Nanos1 by Nanos2 or Nanos3 because the expression of nanos2 and nanos3 was rarely seen in the pharyngeal endoderm and endodermal pouches in wild-type and nanos1 mutant animals during craniofacial development. Our findings suggest that nanos1 expression in the pharyngeal endoderm might be dispensable for craniofacial development in zebrafish.

The transcription factor SOX5 is present in two distinct isoforms in both human and mouse, L-SOX5 and S-SOX5 (long and short isoforms of SOX5). Here, we identified and characterized a novel transcript of Sox5 (S-Sox5 variant) in mouse testis. eCLIP-based amplification of cDNA ends were performed to identify the potential Sox5 mRNA variant. This novel transcript shares a high similarity with the previously reported S-Sox5 in nucleotide sequence, but with a unique stretch of 5′UTR and an additional exon 9. Semi-quantitative PCR analysis revealed both S-Sox5 variant and S-Sox5 express specifically in mouse testis. Both transcripts increase significantly in mouse testis at postnatal day 21, when round spermatids appear. We further made a series of truncated Sox5 constructs and tagged them with eGFP in HeLa cells. In vitro transfection assay identified the N-terminus and the DNA-binding HMG domain are required for the nuclear localization of SOX5. Our results provides a basis for the future study to investigate the biological function of SOX5 in spermatogenesis.

The family with sequence similarity 83 member (FAM83D) plays important role in the process of cell division as well as tumour progression. However, the role of FAM83D in tissue development was not well explored. Here, we assessed transcriptional levels of FAM83D and other possibly related genes in organs of mice at different ages and methylation level of FAM83D promoter. Our results indicate the trend of FAM83D expression in mouse testis, liver, lung and small intestine, and its relationship to CYCLINB1 and KI67. Finally, we found no effect of promoter methylation status on FAM83D expression during mice development.