title: Evolutionary Conservation of pou5f3 Genomic Organization and Its Dynamic Distribution during Embryogenesis and in Adult Gonads in Japanese Flounder Paralichthys olivaceus.
abstract: Octamer-binding transcription factor 4 (Oct4) is a member of POU (Pit-Oct-Unc) transcription factor family Class V that plays a crucial role in maintaining the pluripotency and self-renewal of stem cells. Though it has been deeply investigated in mammals, its lower vertebrate homologue, especially in the marine fish, is poorly studied. In this study, we isolated the full-length sequence ofParalichthys olivaceus pou5f3(Popou5f3), and we found that it is homologous to mammalianOct4. We identified two transcript variants with different lengths of 3'-untranslated regions (UTRs) generated by alternative polyadenylation (APA). Quantitative real-time RT-PCR (qRT-PCR), in situ hybridization (ISH) and immunohistochemistry (IHC) were implemented to characterize the spatial and temporal expression pattern ofPopou5f3during early development and in adult tissues. Our results show thatPopou5f3is maternally inherited, abundantly expressed at the blastula and early gastrula stages, then greatly diminishes at the end of gastrulation. It is hardly detectable from the heart-beating stage onward. We found thatPopou5f3expression is restricted to the adult gonads, and continuously expresses during oogenesis while its dynamics are downregulated during spermatogenesis. Additionally, numerouscis-regulatory elements (CRE) on both sides of the flanking regions show potential roles in regulating the expression ofPopou5f3. Taken together, these findings could further our understanding of the functions and evolution ofpou5f3in lower vertebrates, and also provides fundamental information for stem cell tracing and genetic manipulation inParalichthys olivaceus.
authors.affiliation: College of Marine Life Science, Ocean University of China, Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Qingdao 266003, China. gjn.1127@163.com.|Center for Developmental Cardiology, Institute for Translational Medicine, College of Medicine, Qingdao University, Qingdao 266021, China. gjn.1127@163.com.
authors.forename: Jinning
authors.initials: J
authors.lastname: Gao
authors.affiliation: College of Marine Life Science, Ocean University of China, Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Qingdao 266003, China. wangxubo@ouc.edu.cn.
authors.forename: Xubo
authors.initials: X
authors.lastname: Wang
authors.affiliation: College of Marine Life Science, Ocean University of China, Key Laboratory of Marine Genetics and Breeding, Ministry of Education, Qingdao 266003, China. qzhang@ouc.edu.cn.
authors.forename: Quanqi
authors.initials: Q
authors.lastname: Zhang
mesh_terms: D024506:5' Flanking Region / Q000235:genetics; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002875:Chromosomes / Q000235:genetics; D019295:Computational Biology; D017124:Conserved Sequence / Q000235:genetics*; D047108:Embryonic Development / Q000235:genetics*; D019143:Evolution, Molecular; D005432:Flounder / Q000196:embryology* / Q000235:genetics*; D020869:Gene Expression Profiling; D018507:Gene Expression Regulation, Developmental; D023281:Genomics; D006066:Gonads / Q000196:embryology* / Q000378:metabolism; D007150:Immunohistochemistry; D050814:Octamer Transcription Factor-3 / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D020539:Sequence Analysis, Protein; D012689:Sequence Homology, Nucleic Acid; D026801:Synteny / Q000235:genetics
chemical_list: D050814:Octamer Transcription Factor-3
keywords: Japanese flounder (Paralichthys olivaceus); expression pattern; pou5f3; promoter analysis