摘要
【目的】通过多组学手段,系统解析文蛤丙氨酸含量的遗传基础与调控网络,为风味性状分子育种提供理论依据。【方法】以300只2龄文蛤为材料,测定足组织游离氨基酸含量,综合运用全基因组关联分析(GWAS)、表达全基因组关联分析(eGWAS)、全转录组关联分析(TWAS)及加权基因共表达网络分析(WGCNA),从遗传变异、基因表达及共表达网络层面解析文蛤鲜味氨基酸(丙氨酸)含量的遗传基础与多层次调控网络。【结果】GWAS鉴定到4个与丙氨酸含量显著相关的SNP位点,注释获得PRSS48和FUT11两个候选基因,提示蛋白质代谢与糖基化修饰可能影响丙氨酸积累。GWAS与eGWAS共定位发现chr17:23 364 804位点(PP.H4=1.000),可能通过顺式调控影响下游基因表达。TWAS筛选到25个相关基因,功能涉及信号转导、代谢调控等。WGCNA识别出3个显著相关模块(Magenta、Red、Green),富集通路及蛋白质互作网络分析表明,三者分别主导组织水平代谢协调、底物驱动合成代谢及系统层面免疫清除与稳态维持。【结论】本研究从多组学角度揭示了文蛤丙氨酸含量受多基因微效调控和多通路交叉协同,且由合成、支撑与分解模块构成的动态调控网络协同调控,研究结果为文蛤风味性状的分子标记辅助选择与多基因聚合育种提供了重要候选基因资源和理论支持。
Meretrix petechialis is a commercial marine mollusk widely cultivated along the coastal areas of China,renowned for its delicious flavor.Its rich umami is primarily determined by free amino acids.Among the umami-related amino acids detected in the foot tissue of 300 two-year-old individuals,alanine was identified as the most abundant[(0.351±0.092)g/100 g wet weight]and genetically variable component,making it a key target trait for improving the flavor characteristics.The present study integrated multiple omics approaches,including genome-wide association study(GWAS),expression-based GWAS(eGWAS),transcriptome-wide association study(TWAS),and weighted gene co-expression network analysis(WGCNA),to decipher the genetic architecture and regulatory network governing alanine content.GWAS,based on 9.8 million high-quality SNPs,identified four significantly associated loci on chromosomes 2,4,16,and 17,which explained 8.35%to 9.10%of the phenotypic variation.These loci were annotated to two core candidate genes:PRSS48,which is a serine protease potentially regulates alanine accumulation by promoting protein hydrolysis and precursor supply,and FUT11,which is a fucosyltransferase inferred to modulate the activity and stability of alanine metabolic enzyme through glycosylation.Colocalization analysis between GWAS and eGWAS revealed a highly credible shared causal variant at chr17:23364804(PP.H4=1.000),which overlaps with a cis-eQTL signal of the downstream gene evm_TU_Hic_asm_16_887,indicating cis-regulatory control of gene expression in alanine metabolism.Using transcriptomic data from 100 randomly selected individuals,TWAS identified 30 alanine-correlated genes enriched in signal transduction,metabolic regulation,and post-translational modification pathways.WGCNA further delineated three functionally specialized modules significantly correlated with alanine content:the magenta module(enriched in amino acid metabolism and mTOR signaling),the red module(focused on glycolysis and branched-chain amino acid degradation),and the green module(involved in lysosomal function and detoxification),collectively orchestrating alanine synthesis,storage,and homeostasis.These multi-omics results comprehensively reveal the hierarchical regulatory mechanisms underlying the formation of umami amino acids in M.petechialis,integrating genetic variation,transcriptional regulation,and co-expression networks,providing valuable candidate genes and molecular markers for flavororiented molecular breeding in this commercial important shellfish.
作者
冯星怡
王鸿霞
郇聘
刘保忠
FENG Xingyi;WANG Hongxia;HUAN Pin;LIU Baozhong(State Key Laboratory of Breeding Biotechnology and Sustainable Aquaculture,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Shandong Dehe Mingxing Biotechnology Co.,Ltd.,Weifang 261309,China)
出处
《水产学报》
2026年第5期135-150,共16页
Journal of Fisheries of China
基金
现代农业产业技术体系(CARS-49)
山东省泰山产业领军蓝色专项。
