Expression pattern and developmental behaviour of cellular nucleic acid-binding protein (CNBP) during folliculogenesis and oogenesis in fish.
In vertebrates, folliculogeneis establishes an intricate system for somatic cell-oocyte interaction, and ultimately leads to the acquisition of their respective competences. Although the formation process and corresponding interactions are strikingly similar in diverse organisms, knowledge of genes and signaling pathways involved in follicle formation is very incomplete and the underlying molecular mechanisms remain enigmatic. CNBP has been identified for more than ten years, and the highest level of CNBP transcripts has been observed in adult zebrafish ovary, but little is known about its functional significance during folliculogeneis and oogenesis. In this study, we clone CNBP cDNA from gibel carp (Carassius auratus gibelio), and demonstrate its predominant expression in gibel carp ovary and testis not only by RT-PCR but also by Western blot. Its full-length cDNA is 1402 bp, and has an ORF of 489 nt for encoding a peptide of 163 aa. And its complete amino acid sequence shared 68.5%-96.8% identity with CNBPs from other vertebrates. Based on the expression characterization, we further analyze its expression pattern and developmental behaviour during folliculogeneis and oogenesis. Following these studies, we reveal an unexpected discovery that the CagCNBP is associated with follicular cells and oocytes, and significant distribution changes have occurred in degenerating and regenerating follicles. More interestingly, the CagCNBP is more highly expressed in some clusters of interconnected cells within ovarian cysts, no matter whether the cell clusters are formed from the original primordial germ cells or from the newly formed cells from follicular cells that invaded into the atretic oocytes. It is the first time to reveal CNBP relevance to folliculogeneis and oogenesis. Moreover, a similar stage-specific and cell-specific expression pattern has also been observed in the gibel carp testis. Therefore, further studies on CNBP expression pattern and developmental behaviour will be of significance for understanding functional roles of CNBP during gametogenesis.
Liu
Jing-Xia
JX
State Key Laboratory of Freshwater Ecology and Biotechnology, Wuhan Center for Developmental Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Wuhan 430072, China.
Gui
Jian-Fang
JF
D000595:Amino Acid Sequence; D000818:Animals; D015153:Blotting, Western; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000737:chemistry / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004848:Epithelium / Q000378:metabolism; D005260:Female; D029941:Fish Proteins / Q000235:genetics* / Q000378:metabolism; D016650:Fluorescein-5-isothiocyanate / Q000737:chemistry; D005455:Fluorescent Antibody Technique / Q000379:methods; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D006054:Goldfish / Q000196:embryology / Q000235:genetics*; D008297:Male; D018613:Microscopy, Confocal; D008969:Molecular Sequence Data; D009866:Oogenesis / Q000235:genetics*; D006080:Ovarian Follicle / Q000254:growth & development / Q000378:metabolism*; D010053:Ovary / Q000166:cytology / Q000254:growth & development / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D013997:Time Factors
D018076:DNA, Complementary; D004268:DNA-Binding Proteins; D029941:Fish Proteins; D016601:RNA-Binding Proteins; D016650:Fluorescein-5-isothiocyanate