从SAGE文库筛选的家蚕正反交F_1代3个差异基因的组织表达分析  

An Expressional Analysis on Three Divergent Genes in F_1 Generation of Bombyx mori Reciprocal Crosses by SAGE Library Screening

作　　者：周前凯[1] 张彩霞[1] 王华[1] 魏广兵[1] 李娟[2] 刘腾[1] 金鑫[1] 徐世清[1] 司马杨虎[1] 

机构地区：[1]苏州大学基础医学与生物科学学院,江苏苏州215123 [2]山东农业大学林学院,山东泰安271018

出　　处：《蚕业科学》2013年第4期674-679,共6页ACTA SERICOLOGICA SINICA

基　　金：现代农业产业技术体系专项(No.CARS-22)

摘　　要：家蚕许多数量遗传性状在品种的正反交之间存在明显差异,研究产生性状差异的分子机制对于家蚕育种具有重要指导意义。基于家蚕品种75新与7532正反交F1代同性别间的SAGE文库,比较、筛选出与家蚕抗逆性相关的3个表达差异显著基因——线粒体硫氧还蛋白2(TRx2)基因、谷胱甘肽过氧化物酶(GPx)基因、抗菌肽(AMPs)基因。在幼虫5龄期设置高温(34℃)饲养环境,利用竞争性半定量RT-PCR方法检测3个差异基因在75新与7532的正反交F1代幼虫脂肪体、中肠和丝腺组织中的转录水平。TRx2基因和GPx基因在正反交F1代雌、雄幼虫的3个组织中均有表达,其中:TRx2基因在反交F1代雌、雄幼虫3个组织的转录水平总体上略高于正交F1代,表达趋势为先升高后降低,至5龄第6天的表达最高;GPx基因在正反交F1代雌性幼虫3个组织的转录水平在整个5龄期无明显差异,但雄性幼虫中该基因的转录水平在5龄第3天和第6天以反交F1代雄性幼虫略高,推测其抗氧化性能高于正交F1代雄性幼虫。AMPs基因在正反交F1代幼虫脂肪体中的转录水平最高,且正反交之间、雌雄之间无明显差异,推测该基因在脂肪体中的高水平表达对维持家蚕在高温环境下的体内稳态环境起重要作用。Many genetic quantitative characters have obvious differences between reciprocal crosses of certain silkworm（Bombyx mori） varieties.Elucidation of molecular mechanism causing such differences is of great importance in silkworm breeding.Based on the same sex SAGE comparative library for F1 generation of reciprocal crosses of silkworm variety 75xin and 7532,we screened and obtained three significantly different and adaptability related genes,namely mitochondrial thioredoxin 2（TRx2） gene,glutathione peroxidase（GPx） gene and antibacterial peptides（AMPs） gene.During the 5th larval instar,high temperature（34 ℃） was created for silkworm rearing and competitive semi-quantitative RT-PCR was employed to detect the transcription levels of these three genes in fat body,midgut and silk gland of the F1 larvae of 75xin and 7532 reciprocal crosses.The results displayed that TRx2 gene and GPx gene were both expressed in the three tissues of F1 female and male larvae of reciprocal crosses.In general,the transcription levels of TRx2 gene in the three tissues of F1 female and male larvae of the reverse cross were slightly higher than those of the direct cross.Its expression was in a first increase and then decrease pattern with expression peak on day 6 of the 5th instar.The expression levels of GPx gene in the three tissues showed no significant difference in F1 female larvae of reciprocal crosses during the whole 5th instar.However,the expression levels in F1 male larvae of the reverse cross were slightly higher at day 3 and day 6 of the 5th instar,indicating that its antioxidant ability was higher than F1 male larvae of the direct cross.The expression level of AMPs gene was the highest in fat body with no remarkable difference between reciprocal crosses and different sexes.It is suggested that high expression of this gene in fat body plays an important role in maintaining homeostasis of silkworm in high temperature environment.

关 键 词：家蚕 正反交F1代 差异表达基因 高温 

分 类 号：S882[农业科学—特种经济动物饲养] Q785[农业科学—畜牧兽医]