鱼类的性早熟是在人工养殖过程中出现并影响其生长速度的重要因素之一，生长和性腺发育表现出相互促进-相互抑制的作用。申请人前期青年和面上基金分别探讨了团头鲂HPG轴相关基因和let-7 miRNAs对其生长和性腺发育的调控作用。此课题拟利用团头鲂性早熟和非性早熟家系，运用转录组和代谢组系统研究手段，揭示性早熟过程中生长和性腺发育相关组织基因表达和代谢物含量的变化，构建性早熟过程中生长和性腺发育互作的关键基因-代谢物调控网络，确定候选关键基因和代谢物；基于已获得的团头鲂全基因组，对3-5个关键基因的功能进行活体和细胞水平的基因抑制/敲除/过表达分析；对关键代谢物在性早熟和非性早熟家系不同阶段个体进行定量分析，筛选可鉴别1龄性早熟、1龄非性成熟和2龄正常性成熟个体的活体生物标志物。研究结果将从转录组、代谢组及关键基因/代谢物三个水平系统解析团头鲂性早熟的分子机制及其与生长发育之间互作的调控机制。

Early puberty is one of the major problems in many farmed fish species due to negative effects on growth performance. As a main aquaculture species in the Chinese freshwater polyculture system with high economic value, the Megalobrama amblycephala is gradually exhibiting early sexual maturity under a long cultured period. Through the previous founding projects from National Natural Science Foundation, the applicants have investigated the molecular regulation mechanism of HPG related genes and let-7 miRNAs on the early puberty of M. amblycephala as well the relationship between growth and gonadal development. The present proposed project will further use the transcriptomics and metabonomics technologies to systematically analyze the variations of genes expression and contents of metabolites during the growth and gonadal development stages. The putative key genes and metabolites will be identified. Secondly, based on the whole genome sequencing data which have been finished by our research group, the present study will try to identify the functions of 3-5 keys genes related to early puberty of M. amblycephala. Thirdly, the putative key metabolites will be quantified in a large population to screen the biomarkers to identify the one-year-old early mature, one-year-old immature and two-year-old normal mature females. The results from this project would explain the genetic mechanism and regulation network for the mutual promotion and inhibition relationship of growth and gonadal development from the transcriptome, metabolome and key genes/ metabolites levels, which could offer the reference data for exploring the relationship between growth and gonadal development during individual’s development.