家蚕驯化过程中受到选择的2个GMC氧化还原酶基因的序列变异分析  

Sequence Variation of Two GMC Oxidoreductase Genes with Selective Signals Behind Silkworm Domestication

作　　者：程道军[1] 唐林[1] 孟勐[1] 王永虎[1] 夏庆友[1] 

机构地区：[1]家蚕基因组生物学国家重点实验室,西南大学,重庆400715

出　　处：《蚕业科学》2014年第2期210-215,共6页ACTA SERICOLOGICA SINICA

基　　金：国家自然科学基金项目(No.31172267);重庆市自然科学基金项目(No.cstc2012jjA80023);国家重点基础研究发展计划"973"项目(No.2012CB114600);国家高技术研究发展计划"863"项目(No.2011AA100306)

摘　　要：葡萄糖-甲醇-胆碱(glucose-methanol-choline,GMC)氧化还原酶家族在生物体内葡萄糖、胆碱和甾醇等物质的代谢过程中发挥重要作用。比较家蚕和野桑蚕的遗传变异图谱数据发现,GMC氧化还原酶基因家族成员GMC1(BGIBMGA000068)和GMC2(BGIBMGA000158)在家蚕驯化过程中受到显著的选择压力,其完整基因序列发生大量单核苷酸多态性(single-nucleotide polymorphism,SNP)突变,部分SNP突变位于外显子区并导致所编码蛋白质的氨基酸发生替换。基于全基因组芯片数据的表达谱分析显示,GMC1基因主要在家蚕5龄第3天幼虫的中肠和马氏管中表达,GMC2基因主要在丝腺和头部高量表达,暗示GMC1和GMC2在家蚕驯化过程中发生的序列变异可能与其在家蚕体内物质代谢及丝腺发育或丝蛋白合成等生物学过程中的功能有关。从家蚕丝腺组织中克隆获得家蚕GMC2基因的全长cDNA序列并进行原核表达,目的蛋白质以包涵体的形式存在。Glucose-methanol-choline （GMC） oxidoreductase family plays important roles in the metabolism of glucose, choline, sterol and other substances in various organisms. By analyzing genetic variation data between the domesticated silkworm （Bombyx mori） and wild silkworm （Bombyx mandarina）, we found that the genomic sequences of two genes coding for GMC oxidoreductases, GMCl （BGIBMGA000068） and GMC2 （ BGIBMGA000158）, had undergone signifi- cant selection during silkworm domestication. Comparing to Bombyx mandarina, many single-nucleotide polymorphism （SNP） mutations occurred in the sequences of GMCl and GMC2 from Bombyx mori, and several SNPs in the exons re- suited in amino acid substitutions. An expression profile analysis based on whole genome microarray data indicated that GMCl was expressed mainly in the midgut and Malpighian tubule of Bombyx mori larvae at day 3 of the 5th instar, andGMC2 exhibited very high expression level in the silk gland and head, which suggested that the sequence variation of GMCl and GMC2 may be related to their dif- ferent roles in metabolism, silk gland development or silk protein biosynthesis in silkworm. Furthermore, the full- length cDNA sequence of Bombyx mori GMC2 gene was cloned and expressed in prokaryote. The target protein was expressed as inclusion body.

关 键 词：家蚕 驯化 葡萄糖-甲醇-胆碱氧化还原酶 序列变异 基因表达 

分 类 号：S881.2[农业科学—特种经济动物饲养] Q785[农业科学—畜牧兽医]