家蚕卵黄原蛋白及其受体基因  

Vitellogenin and vitellogenin receptor gene of the silkworm Bombyx mori

作　　者：林英[1] 赵萍[1] 侯勇[1] 李娟[1] 龚达平[1] 孙全[1] 夏庆友[1] 向仲怀[1] 

机构地区：[1]西南农业大学蚕学与生物技术学院,农业部蚕桑学重点开放实验室,重庆400716

出　　处：《动物学报》2005年第1期117-125,共9页ACTA ZOOLOGICA SINICA

基　　金：国家自然科学基金重点项目 (No 3 0 3 3 0 460 );国家教育部博士点基金 (No 2 0 0 40 62 5 0 11);重庆市教委项目 (No 0 3 0 2 0 5 )资助~~

摘　　要：家蚕小卵突变体 (Smalleggmutant ,sm) ,其卵体积仅及正常卵的 2 / 3,不能受精而致死。因其卵母细胞不能正常吸收卵黄原蛋白 (Vg) ,人们认为其原因可能是卵黄原蛋白受体基因 (VgR)突变所致。本研究首先通过克隆筛选和基因组序列分析 ,获得了 2 5 6 4bp含有 ployA的家蚕卵黄原蛋白受体基因 (BmVgR)片段。将该基因片段的预测蛋白与其它物种的VgR/YPR和低密度脂蛋白受体 (LDLR)家族比较 ,发现该基因具有LDLR家族的基本结构特征。其次 ,经RT PCR检测 ,结果表明BmVgR在sm的不同时期的卵母细胞中都能正常转录。最后 ,分别对sm不同发育时期的体液和卵的总蛋白进行SDS PAGE分析 ,发现该突变体的卵母细胞不能正常摄取体液蛋白 (包括Vg)。综合分析 ,sm不能正常摄取Vg ,可能并不是VgR的功能异常导致 。The egg produced by the small egg mutant (sm) of silkworm is about two-thirds the size of the normal one.The mutant can not be impregnated and dies accordingly since its oocyte is abnormal to absorb vitellogenin (Vg).It was believed that sm might be caused by the mutational gene of vitellogenin receptor (VgR).In this study we obtained a 2 564 bp cDNA fragment of silkworm vitellogenin receptor (BmVgR) gene with a polyA tail by using of the EST clones and the sequence of the silkworm genome.Sequences analysis showed that the predicted protein of the gene is basically characteristic of the low-density lipoprotein receptor superfamily (LDLR) when compare it with VgR/YPR and LDLR of other species.RT-PCR indicated that the BmVgR gene can be normally transcribed in different stages of sm oocyte.The total proteins of hemolymph and those of eggs in different stages were respectively analyzed by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate (SDS-PAGE).The results showed that the oocyte of sm had an impaired uptake of the total proteins of hemolymph, including Vg.It came to the conclusion in this study that the impaired uptake results from an abnormal follicle cell, not from an impaired VgR in the sm

关 键 词：正常 受体基因 摄取 白及 体液 低密度脂蛋白受体 功能异常 家蚕卵 卵黄原蛋白 卵母细胞 

分 类 号：S881[农业科学—特种经济动物饲养]