Wang Na, Wang Ruoqing, Hu Qiaomu, Xu Wenteng, Zhu Ying, Yan Fang, Chen Songlin
Key Laboratory for Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Qingdao, 266071, China.
Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China.
Fish Physiol Biochem. 2017 Oct;43(5):1289-1298. doi: 10.1007/s10695-017-0372-1. Epub 2017 Jul 24.
As an important economic marine species cultured in China, Chinese tongue sole (Cynoglossus semilaevis) has interested us due to its sexual dimorphism and ZW/ZZ sex determination system. In a previous study, dmrt1 was identified as a dosage-dependent male-determining gene. In the present study, a female-specific expressed gene, cse0440, initially annotated as lrp1b-like, was identified from chromosome W of C. semilaevis. In view of the differences between cse0440 and lrp1b in terms of expression pattern, a phylogenetic analysis containing 85 LRP proteins was constructed and provided an evidence to re-annotate cse0440 as cseLRP13. In addition, two orthologues of cseLRP13 were separately identified from W and Z chromosomes: cseLRP13-W and cseLRP13-Z. The subsequent multiple sequence alignment and syntenic arrangements of LRP13 in C. semilaevis, Japanese medaka (Oryzias latipes), large yellow croaker (Larimichthys crocea), striped bass (Morone saxatilis), white perch (Morone americana) and Fugu rubripes (Takifugu rubripes) further supported this re-annotation. RT-PCR and in situ hybridization revealed that cselrp13 was exclusively expressed in the oocytes and follicles of ovaries. These results suggested that lrp13 may play important roles in female reproduction. In future, with the advancement of micromanipulation in flatfish, the detailed function of two lrp13 orthologues in C. semilaevis will be elucidated.
半滑舌鳎作为中国重要的海水养殖经济鱼类，因其雌雄异型和ZW/ZZ性别决定系统而备受关注。在之前的研究中，dmrt1被鉴定为剂量依赖性雄性决定基因。在本研究中，从半滑舌鳎W染色体上鉴定出一个雌性特异性表达基因cse0440，最初注释为类lrp1b。鉴于cse0440与lrp1b在表达模式上的差异，构建了包含85个LRP蛋白的系统发育分析，为将cse0440重新注释为cseLRP13提供了证据。此外，分别从W和Z染色体上鉴定出cseLRP13的两个直系同源基因：cseLRP13-W和cseLRP13-Z。随后对半滑舌鳎、日本青鳉、大黄鱼、条纹鲈、白鲈和红鳍东方鲀中LRP13的多序列比对和共线性排列进一步支持了这一重新注释。RT-PCR和原位杂交显示，cselrp13仅在卵巢的卵母细胞和卵泡中表达。这些结果表明，lrp13可能在雌性生殖中发挥重要作用。未来，随着鲆鲽类显微操作技术的进步，半滑舌鳎中两个lrp13直系同源基因的详细功能将得到阐明。
