基因组或亚基因组整入致鱼类生长性状改良的遗传机制

针对基因组或亚基因组整入可导致多倍体鱼类生长性状改良的前期发现，本项目试图从基因组解析、转录组表达特征和表观遗传变化追踪等研究，深入探讨基因组或亚基因组整入如何创制新种质导致养殖鱼类生长性状改良这一与水产动物遗传育种相关的关键科学问题。项目的研究思路是通过创制银鲫新多倍体，分析其父本基因组或染色体整入导致的亲本染色体丢失、重排等变化；解析新多倍体及其亲本生长发育不同阶段转录表达特征及动态变化，揭示不同来源基因组或亚基因组的偏向保留和兼容特征；揭示父母本基因组整合后产生的变化对新多倍体表型特别是生长性状的影响；分析转录动态变化与DNA甲基化、组蛋白修饰以及启动子区转座子变异之间的关联；揭示与生长性状关联的基因共表达模块和枢纽基因；鉴定嵌合或融合基因与新性状间的关联。通过本研究，试图从基因组结构、转录协调和新基因产生三个层面揭示不同来源基因组或亚基因组整合导致鱼类生长性状改良的遗传机制。

Focusing on previous findings that genome or sub-genome integration is able to lead to growth trait improvement in polyploid fish, this project will perform comprehensive analyses of genome, transcriptome and epigenetics, and attempt to explore the key scientific problem of genetic breeding that how genome or sub-genome integration create novel genetic resources and improve growth trait of aquaculture fish. The research framework and purpose include: to synthetize and screen gibel carp neo-polyploids with different growth performances, to analyze loss and/or rearrangement of parental chromosomes in the neo-polyploids, to analyze transcriptional landscape of neo-polyploids and their parents at different stages of development and growth, to reveal the biased retention and compatibility of genomes or sub-genomes, to exploit the changed effects of post-genome integration on phenotype and economic traits, especially growth trait, to analyze the association among dynamic expression changes, DNA methylation, histone modification and/or transposon variation in promoter region, and to identify the co-expressed gene networks, modules and hub genes which are highly associated with growth traits, as well as some chimeric or fusion genes that are related to the new traits. Through this study, we attempt to reveal genetic mechanisms on growth trait improvement in aquaculture fish caused by genome or sub-genome integration from three aspects, such as genome structure, transcriptional coordination and new gene creation.