家蚕金属羧肽酶基因家族的鉴定与表达分析
Identification and Expression Analysis of Metallocarboxypeptidase Gene Family in Silkworm, Bombyx mori
朱玉苹 1韩民锦 1查绪乐 1陈瑜 1沈以红1
作者信息
- 1. 家蚕基因组生物学国家重点实验室,农业部蚕桑功能基因组与生物技术重点实验室,重庆400715
- 折叠
摘要
金属羧肽酶是昆虫消化管中参与食物消化吸收的重要酶类,并可能在昆虫变态、发育、抗病免疫等多种生命过程中发挥重要作用.利用家蚕全基因组数据库,基于同源搜索和隐马尔可夫模型搜索相结合的方法,对家蚕金属羧肽酶基因家族进行鉴定.全基因组预测家蚕的金属羧肽酶基因家族包括22个成员,推导的氨基酸序列均具有锌离子结合位点和金属羧肽酶M14的保守特征.根据其保守氨基酸序列不同,家蚕的金属羧肽酶分属于M14A、M14B和M14D3个亚家族.通过RT-PCR方法检测显示22个家蚕金属羧肽酶基因中有18个基因在家蚕不同组织和发育时期中表达,其中7个基因在家蚕5龄第3天幼虫中肠组织特异高量表达,提示金属羧肽酶在家蚕对营养物质的消化吸收中有重要作用;家蚕5龄幼虫添食感染BmNPV后24h内,中肠中有5个金属羧肽酶基因上调表达,表现出对病原微生物侵染的应答反应.研究结果有助于解析家蚕金属羧肽酶在蚕体对营养物质的消化和对病原物入侵应答中的功能作用.
Abstract
Metallocarboxypeptidase is a crucial enzyme in the digestive tract of insect,and maybe contributes to the processes of insect metamorphosis,development,and resistance.Based on the whole genome database of silkworm (Bombyx mori),metallocarboxypeptidase genes in silkworm were identified by the methods of homology search and hidden Markov model.The predicted results showed that there are 22 metallocarboxypeptidase genes in silkworm and the deduced amino acid sequences all had a zinc ion binding site and conserved sequences of metallocarboxypeptidase M14.According to the conserved amino acid sequence,these metallocarboxypeptidase genes in silkworm are classified into M14A,M14B and M14D subfamilies.RT-PCR indicated that 18 metallocarboxypeptidase genes were expressed in different tissues and developmental stages,in which 7 genes were highly expressed in midgut tissue of day 3 larvae of the 5th silkworm instar,indicating that metallocarboxypeptidases play an important role in the digestion and absorption of nutrients in silkworm.Furthermore,the expression level of 5 metallocarboxypeptidase genes were up-regulated in midgut tissue of the 5th instar silkworm larvae after infection with Bombyx mori nucleopolyhedrovirus (BmNPV) virus whithin 24 h,showing response to the infection of pathogenic microorganisms.The obtained results laid a foundation for illustrating the functions of silkworm metallocarboxypeptidase in nutrient substance digestion and response to pathogenic microorganism infection.
关键词
金属羧肽酶基因/全基因组预测/序列结构/表达分析Key words
Metallocarboxypeptidase gene/Genome-wide prediction/Sequence structure/Expression analysis引用本文复制引用
基金项目
公益性行业(农业)科研专项(201403049)
出版年
2016
NETL
NSTL
维普
万方数据