家蚕羧酸酯酶基因BmCarE-9的鉴定与表达分析  

Identification and expression analysis of carboxylesterase gene BmCarE-9 in Bombyx mori

作　　者：林超[1,2] 李兵[1,3,2] 王东[1,2] 赵国栋[1,2] 卫正国[1,3,2] 陈玉华[1,3,2] 沈卫德[1,3,2] 

机构地区：[1]现代丝绸国家工程实验室,江苏苏州215123 [2]苏州大学基础医学与生物科学学院,江苏苏州215123 [3]苏州大学蚕桑研究所,江苏苏州215123

出　　处：《昆虫学报》2011年第5期495-501,共7页Acta Entomologica Sinica

基　　金：国家自然科学基金项目(31072086);苏州市科技项目(SYN201009)

摘　　要：羧酸酯酶是一个多功能超家族酶类,为研究羧酸酯酶基因在家蚕Bombyxmori组织中的功能,利用5′/3′RACE和RT-PCR方法克隆了一个家蚕羧酸酯酶基因BmCarE-9,其GenBank登录号为EU523534。该基因含有一个1 680 bp的ORF,编码559个氨基酸。BmCarE-9预测的分子量64.2 kD,等电点7.13,结构分析表明BmCarE-9存在一个类似的催化三联体,其中两个残基发生改变。利用实时荧光定量PCR方法研究了该基因在家蚕5龄第3天幼虫不同组织以及在5龄期各日龄幼虫丝腺组织中的表达水平。结果表明,该基因在丝腺中特异性高表达,且主要在中部和后部丝腺中表达。该基因在5龄期随着丝腺的生长发育表达量逐渐增高,到末期表达水平逐渐降低。据此推测该基因可能与丝腺的生长发育或丝蛋白的合成相关。Carboxylesterase is a multifunctional superfamily.To determine the function of carboxylesterase in different tissues of Bombyx mori,we cloned a carboxylesterase gene named BmCarE-9（GenBank accession no.EU523534） from B.mori by using rapid amplification of cDNA ends（RACE） and reverse transcription polymerase chain reaction（RT-PCR） methods.BmCarE-9 contains a 1 680 bp open reading frame（ORF）,which encodes 559 amino acids.This cDNA-deduced protein BmCarE-9 has a predicted molecular weight（MW） of 64.2 kD,and isoelectric point（pI） of 7.13.Structure analysis showed that BmCarE-9 has a similar catalytic triad in which two residues have changed.We investigated the developmental expression patterns of BmCarE-9 in different tissues of the Day-3 5th instar larvae and in silk glands of different day-old 5th instar larvae by real-time quantitative PCR.The results showed that BmCarE-9 was expressed specifically in silk glands at high levels,and mainly expressed in the median and posterior silk glands.Furthermore,the expression of BmCarE-9 increased as silk glands developed,and decreased at the end of 5th instar stage.It is so inferred that BmCarE-9 might be involved in the development of silk glands or the synthesis of silk proteins.

关 键 词：家蚕 BmCarE-9 丝腺 实时荧光定量PCR 组织表达 

分 类 号：Q965[生物学—昆虫学]