籽鹅羽束性状分析及SOX5候选基因生物学功能预测

Analysis of crest trait and prediction of biological function of candidate gene SOX5 in Zi-goose

目的分析籽鹅头顶部的表型性状-羽束性状(crest trait),并预测SOX5候选基因的相关生物学功能,从而进一步揭示禽类表型性状与调控基因的作用机制。方法选取无羽束公鹅6只,有、无羽束母鹅各15只,建立两个资源群体,有羽束群(crest population,C):3只无羽束公鹅,15只有羽束母鹅;无羽束群(non-crest population,NC):3只无羽束公鹅,15只无羽束母鹅。两个试验群体同舍分组饲养,收集试验蛋孵化,通过后代表型分离比,分析羽束性状遗传规律。采集1、14、21日龄肝脏、头顶部皮肤组织,采用qRT-PCR方法测定各组织中SOX5基因相对表达量,并通过生物信息方法进行关联性分析。结果观察籽鹅表型分离比,证明无羽束性状符合隐性遗传规律,有羽束性状受常染色体显性基因调控。在1日龄雏鹅肝脏组织中,C群SOX5基因的相对表达量显著高于NC群(P <0. 01),其他时期差异虽无统计学意义(P> 0. 05),但C群仍高于NC群。随日龄增长,公鹅体重呈上升趋势,且与SOX5基因在皮肤中相对表达量变化趋势相同。经SMART、David软件预测,SOX5基因具有保守结构域,能形成具有生物学功能蛋白。结论籽鹅羽束性状类似于鸡冠表型遗传方式,受常染色体基因调控,SOX5基因为羽束性状的调控基因,且广泛参与禽类相关组织的发育过程。

Objective To analyze the phenotypic trait of top head of Zi-geese(crest trait)and predict the biological function of candidate gene SOX5 so as to further reveal the phenotypic trait of poultry as well as the action mechanism of regulatory gene.Methods Six male geese without crest,15 female geese with and 15 female geese without crest were selected to establish two resource populations,i.e.crest(C)population consisting of 3 male geese without crest and 15 female geese with crest and non-crest(NC)population consisting of 3 male geese without crest and 15 female geese without crest.The two populations were subjected to group feeding in the same birdhouse,and the eggs were collected and hatched to observe the phenotypic separation ratio of offspring,based on which the genetic regularity of crest trait was analyzed.The expression levels of SOX5 gene in liver and head skin tissues of offspring at ages of 1,14 and 21 days were determined by qRT-PCR for analysis of association by Bioinformatics.Results The phenotypic separation ratio showed that the non-crest trait were in line with the regularity of recessive inheritance,while the crest trait were regulated by autosomal dominant genes.The relative expression level of SOX5 gene in liver tissue of offspring at age of one day was significantly higher in C population than in NC population(P<0.01),while those at the other ages were insignificantly higher(P>0.05).The body weight of male geese showed an increasing tendency with the increasing age,which was consistent with the change tendency of relative expression level of SOX5 gene in skin.The prediction by the SMART and David software showed a conservative domain of SOX5 gene,with a capable of forming biologically functional protein.Conclusion The crest trait of Zi-geese is similar to the phenotype inheritance of comb,which is regulated by autosomal genes.SOX5 is the regulatory gene of crest trait,which participates in the development process of the relevant poultry tissues.