Key Laboratory of Mariculture, Ministry of Education, Ocean University of China, Qingdao, 266003, China.
Laboratory for Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
Mar Biotechnol (NY). 2018 Apr;20(2):206-219. doi: 10.1007/s10126-018-9798-4. Epub 2018 Mar 8.
The Pacific oyster Crassostrea gigas is a commercially important bivalve in aquaculture worldwide. C. gigas has a fascinating sexual reproduction system consisting of dioecism, sex change, and occasional hermaphroditism, while knowledge of the molecular mechanisms of sex determination and differentiation is still limited. In this study, the transcriptomes of male and female gonads at different gametogenesis stages were characterized by RNA-seq. Hierarchical clustering based on genes differentially expressed revealed that 1269 genes were expressed specifically in female gonads and 817 genes were expressed increasingly over the course of spermatogenesis. Besides, we identified two and one gene modules related to female and male gonad development, respectively, using weighted gene correlation network analysis (WGCNA). Interestingly, GO and KEGG enrichment analysis showed that neurotransmitter-related terms were significantly enriched in genes related to ovary development, suggesting that the neurotransmitters were likely to regulate female sex differentiation. In addition, two hub genes related to testis development, lncRNA LOC105321313 and Cg-Sh3kbp1, and one hub gene related to ovary development, Cg-Malrd1-like, were firstly investigated. This study points out the role of neurotransmitter and non-coding RNA regulation during gonad development and produces lists of novel relevant candidate genes for further studies. All of these provided valuable information to understand the molecular mechanisms of C. gigas sex determination and differentiation.
太平洋牡蛎（Crassostrea gigas）是全球水产养殖中一种重要的商业双壳贝类。C. gigas 具有迷人的性繁殖系统，包括雌雄异体、性别转换和偶尔的雌雄同体，而对性别决定和分化的分子机制的了解仍然有限。在这项研究中，通过 RNA-seq 对不同配子发生阶段的雌雄性腺转录组进行了表征。基于差异表达基因的层次聚类表明，有 1269 个基因特异性表达于雌性性腺，817 个基因在精子发生过程中呈递增表达。此外，我们使用加权基因共相关网络分析（WGCNA）分别鉴定出了与雌性和雄性性腺发育相关的两个和一个基因模块。有趣的是，GO 和 KEGG 富集分析表明，与卵巢发育相关的基因中显著富集了神经递质相关术语，表明神经递质可能调节雌性性别分化。此外，首次研究了两个与睾丸发育相关的枢纽基因，lncRNA LOC105321313 和 Cg-Sh3kbp1，以及一个与卵巢发育相关的枢纽基因 Cg-Malrd1-like。本研究指出了神经递质和非编码 RNA 在性腺发育过程中的调节作用，并产生了一系列新的相关候选基因，以供进一步研究。所有这些都为理解 C. gigas 性别决定和分化的分子机制提供了有价值的信息。
