半滑舌鳎性逆转跨代遗传的表观调控机制

项目名称： 半滑舌鳎性逆转跨代遗传的表观调控机制

项目编号： No.31472269

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 农业科学

项目作者： 邵长伟

作者单位： 中国水产科学研究院黄海水产研究所

项目金额： 88万元

中文摘要： 表观遗传介导基因和环境互作，被喻为生命天书的第二种编码形式。鱼类性别决定和分化是理解基因和环境相互博弈的绝佳案例。本项目组前期研究发现半滑舌鳎存在环境介导的性逆转跨代遗传现象，导致实际生产中雌雄比例严重失调，从而影响半滑舌鳎产业的规模化发展。因此，本项目拟以半滑舌鳎性逆转跨代遗传为出发点，采用高通量测序技术开展半滑舌鳎伪雄鱼（ZW♂）和正常雄鱼（ZZ♂）后代早期发育的全基因组甲基化测序和转录组测序，绘制早期发育的基因动态表达图谱和甲基化图谱。筛选表征伪雄鱼后代早期发育各阶段的特异基因，揭示伪雄鱼W精子失活后Z染色体基因的剂量平衡机制。同时鉴定伪雄鱼（ZW♂）和正常雄鱼（ZZ♂）后代早期发育各阶段的差异甲基化基因，筛选参与跨代遗传的印记基因。利用RNAi技术特异性沉默关键印记基因，阐明印记基因在伪雄鱼后代基因组重编程中逃逸的分子机制，从而解析半滑舌鳎Z染色体介导的性逆转跨代显性遗传机制。

中文关键词： 半滑舌鳎；性逆转；跨代遗传；DNA甲基化；转录组

英文摘要： Epigenetics, involving the interaction between genomic and environmental information, is considered the second coding for life forms. Fish sex determination and differentiation are processes where to investigate the influence of epigenetics versus classical genetics. In a previous study, we found the existence of transgenerational inheritance of sex reversal in tongue sole, leading to a non-adaptive sex ratio that is skewed towards predominantly male offspring, thus affecting the development of large-scale tongue sole industry. In this study, taking such an intriguing phenomenon as a starting point, we plan to carry out the whole-genome methylation sequencing and transcriptome sequencing for the early development stages of tongue sole pseudo-male (ZW♂) and normal male (ZZ♂) offspring, respectively. First, we will create dynamic maps of methylation patterns and gene expression profiles related to different aspects of sex determination. Further, we will screen the specific genes that are expressed in each developmental stage and those genes that experience a shift of expression between different stages, revealing the dosage expression mechanism of Z-linked genes after the inactivation of W sperm in pseudo-male (ZW♂). Meanwhile, we will identify the differentially methylated genes (DMGs) between pseudo-male (ZW♂) and normal male (ZZ♂) on the corresponding stages of early development of the offspring. Consequently, we can isolate the imprinted genes involved in the transgenerational inheritance of sex reversal in tongue sole. We will then silence the imprinted genes by RNAi to elucidate the molecular mechanism of imprinted genes that escape genomic reprogramming in the development of pseudo-male offspring, thereby revealing the transgenerational epigenetic inheritance of sex reversal in half-smooth tongue sole mediated by monoallelic expression of Z chromosomal genes.

英文关键词： Half-smooth tongue sole;Sex reversal;Transgenerational inheritance;DNA methylation;Transcriptome