Dong Zhongdian, Li Xueyou, Yao Zebin, Wang Chun, Guo Yusong, Wang Qian, Shao Changwei, Wang Zhongduo
Guangdong South China Sea Key Laboratory of Aquaculture for Aquatic Economic Animals, Fisheries College, Guangdong Ocean University, Zhanjiang 524025, China.
Guangdong Provincial Engineering Laboratory for Mariculture Organism Breeding, Fisheries College, Guangdong Ocean University, Zhanjiang 524025, China.
Animals (Basel). 2021 May 6;11(5):1327. doi: 10.3390/ani11051327.
Hainan medaka () is distributed in the coastal waters of the South China Sea and is able to adapt to a wide range of salinities. In this study, we characterized in Sanya River (SY-medaka), which lacks (a male sex-determining gene in and ). In a comparison of SY-medaka and Gaoqiao medaka (GQ-medaka), the morphological difference between the two populations does not reach the subspecies level and they can be considered two geographic populations of . A mitochondrial cytochrome oxidase subunit I (CoI) sequence alignment showed that the sequence identities between SY-medaka and other geographic populations of are as high as 95%. A phylogenetic analysis of the mitochondrial genome also indicated that SY-medaka belongs to . Molecular marker-based genetic sex assays and whole genome re-sequencing showed that SY-medaka does not contain . Further, in RNA-Seq analyses of the testis and ovaries of sexually mature SY-medaka, expression was not detected. We speculate that high temperatures resulted in the loss of in SY-medaka during evolution, or the lineage has another sex-determining gene. This study provides a valuable dataset for elucidating the mechanism underlying sex determination in genus and advances research on functional genomics or reproduction biology in .
海南青鳉分布于中国南海沿岸水域，能够适应广泛的盐度范围。在本研究中，我们对三亚河青鳉（SY-青鳉）进行了特征描述，该种群缺乏DMY（青鳉和弓背青鳉中的一个雄性性别决定基因）。在SY-青鳉和高桥青鳉（GQ-青鳉）的比较中，两个种群之间的形态差异未达到亚种水平，它们可被视为青鳉的两个地理种群。线粒体细胞色素氧化酶亚基I（CoI）序列比对显示，SY-青鳉与青鳉其他地理种群之间的序列同一性高达95%。线粒体基因组的系统发育分析也表明SY-青鳉属于青鳉。基于分子标记的遗传性别鉴定和全基因组重测序表明，SY-青鳉不含DMY。此外，在性成熟SY-青鳉的睾丸和卵巢的RNA测序分析中，未检测到DMY表达。我们推测，高温导致SY-青鳉在进化过程中失去了DMY，或者该谱系有另一个性别决定基因。本研究为阐明青鳉属性别决定的潜在机制提供了有价值的数据集，并推动了青鳉功能基因组学或生殖生物学的研究。
