Identification of global alternative splicing and sex-specific splicing via comparative transcriptome analysis of gonads of Chinese tongue sole (<i>Cynoglossus semilaevis</i>)
Yifang Lu, 宁波大学海洋学院, 浙江 宁波 315211, 中国, Qian Liu, Kaiqiang Liu, Hongyan Wang, Chenghua Li, Qian Wang, Changwei Shao, 中国水产科学院黄海水产研究所, 农业部海洋渔业可持续发展重点实验室, 山东 青岛 266071, 中国, 青岛海洋科学与技术试点国家实验室, 海洋渔业科学与食物产出过程功能实验室, 山东 青岛 266000, 中国, 上海海洋大学水产与生命学院, 上海 201306, 中国
Abstract
Chinese tongue sole (<i>Cynoglossus semilaevis</i>) is an economically important marine fish species with a ZZ/ZW sex determination mechanism, which can be influenced by temperature. Alternative splicing (AS) is an important mechanism regulating the expression of genes related to sex determination and gonadal differentiation, but has rarely been reported in fish. In this study, to explore the molecular regulatory mechanisms of sex determination and gonadal differentiation, we combined isoform and RNA sequencing (Iso-Seq and RNA-Seq) to perform transcriptome profiling of male and female gonads in <i>C. semilaevis</i>. In total, 81 883 and 32 341 full-length transcripts were obtained in males and females, respectively. A total of 8 279 AS genes were identified, including 2 639 genes showing differential AS (DAS) between males and females. Many intersecting DAS genes and differentially expressed genes (DEGs) were enriched in the meiotic cell cycle pathway, and genes related to gonadal differentiation, such as <i>esrrb</i> and <i>wt1a</i>, were found to have sex-specific isoforms. Thus, this study revealed AS events in the gonadal transcriptomes of male and female <i>C. semilaevis</i>, described the characteristics of active transcription in the testes, and identified candidate genes for studying the regulatory mechanisms of AS during gonadal differentiation.