长江刀鲚GHRH基因遗传多态性及其与生长性状的关联分析  

Growth Hormone Releasing Hormone(GHRH)Gene PolymorphismsAssociated with Growth Traits in Coilia ectenes

作　　者：于爱清 施永海 徐嘉波 刘永士 邓平平 YU Aiqing;SHI Yonghai;XU Jiabo;LIU Yongshi;DENG Pingping(Shanghai Fisheries Research Institute,Shanghai Fisheries Technology Extension Station,Shanghai 200433,China)

机构地区：[1]上海市水产研究所,上海市水产技术推广站,上海200433

出　　处：《西北农业学报》2024年第6期997-1007,共11页Acta Agriculturae Boreali-occidentalis Sinica

基　　金：上海市自然科学基金(19ZR1477900);上海市科技兴农重点攻关项目[沪农科攻字(2016)第6-2-2号]。

摘　　要：生长激素释放激素(GHRH)是鱼类生长激素合成和分泌的重要调控因子,对细胞的生长、增殖和分化极为重要。基于长江刀鲚转录组测序数据,利用基因克隆和PCR扩增技术,获得其GHRH基因的cDNA全长和基因组DNA序列,并开展基因遗传多态性与生长性状的关联性研究,为其分子标记辅助育种提供技术支持。结果显示:长江刀鲚GHRH基因cDNA全长1329 bp,由5′-UTR(300 bp)、ORF(465 bp)和3′-UTR(564 bp)组成,推导的蛋白序列由154个氨基酸组成,具有一个信号肽和GLUCA结构域;该基因的DNA序列长2983 bp,由4个内含子和5个外显子组成,经筛选,在第1、2内含子和第3外显子上分别筛选到9、2和1个SNP位点;12个突变位点共36种基因型,分别与100尾长江刀鲚的体质量、体长和体高性状进行关联分析,获得2个与其生长性状显著相关的位点(g.1636C>T和g.1882A>C)(P<0.05),CC基因型均是优势基因型;利用12个SNP位点分析刀鲚养殖群体的遗传多样性,获得的观测杂合度(HO)、期望杂合度(HE)和多态信息含量(PIC)分别为0.270~0.620、0.338~0.490和0.281~0.370;哈迪-温伯格平衡(HWE)检测结果显示,12个SNP位点中有4个位点显著偏离哈迪-温伯格平衡(P<0.05)。结果表明,长江刀鲚GHRH基因上位点g.1636C>T和g.1882A>C可以作为优选长江刀鲚繁育亲本的重要候选分子标记。To assess the association of polymorphisms of GHRH gene with the growth-related traits in Coilia ectenes,we cloned the cDNA full-length sequence and DNA sequence of GHRH gene,and further identified and validated single nucleotide polymorphisms(SNPs)in this gene.Based on the transcriptome data of C.ectenes,the cDNA full-length sequence and DNA sequence of GHRH gene were obtained by gene cloning technology.SNPs in GHRH gene were identified and genotyped in 100 individuals by DNA direct sequencing and SnaPshot method,respectively.Least squares method was used for association analysis between SNPs and growth traits in C.ectenes.Total cDNA length of GHRH gene of C.ectenes was 1329 bp,containing a 5′-UTR of 300 bp,3′-UTR of 564 bp and an open reading frame of 465 bp.The precursor peptide of GHRH contained 154 amino acids(aa),which included a signal peptide of 19 aa and a GLUCA domain of 27 aa.The genomic DNA of GHRH gene was 2983 bp in length and contained four introns and five exons.Twelve polymorphic sites(SNPs)were identified in intron 1(9),intron 2(2)and exon 3(1).Two SNPs of g.1636C>T in intron 1 and g.1882A>C in intron 2 were significantly associated with the body length,body height and body mass traits(P<0.05),while the other sites were not significantly associated with all three growth traits(P>0.05).Population genetic analysis of cultured population of C.ectenes showed that,among these twelve SNPs,the observed heterozygosity(HO),expected heterozygosity(HE)and polymorphism information content(PIC)were 0.270-0.620,0.338-0.490 and 0.281-0.370,respectively.This study provides useful information for further studies on genetic evaluation of germplasm resources and marker assisted selection(MAS)in C.ectenes.

关 键 词：长江刀鲚 GHRH 单核苷酸多态性 生长性状 关联分析 

分 类 号：S917.4[农业科学—水产科学]