文献类型：期刊文献

英文题名：Molecular cloning and expression analysis of glucose-regulated protein 78 (GRP78) gene in silkworm Bombyx mori

作者：Xi, Xing-Zi[1];Ma, Ke-Shi[2]

第一作者：席兴字

通讯作者：Ma, KS[1]

机构：[1]Xinxiang Univ, Dept Educ Sci, Xinxiang 453003, Peoples R China;[2]Zhoukou Normal Univ, Coll Life Sci, Zhoukou 466001, Peoples R China

第一机构：新乡学院教育科学学院

通讯机构：[1]corresponding author), Zhoukou Normal Univ, Coll Life Sci, Zhoukou 466001, Peoples R China.

年份：2013

卷号：68

期号：3

起止页码：559-564

外文期刊名：BIOLOGIA

收录：;Scopus(收录号：2-s2.0-84876081564);WOS:【SCI-EXPANDED(收录号:WOS:000317645900024)】；

基金：We thank Dr. Oliver Clarke and Youzhong Guo from Columbia University for critical reading of this manuscript. This work was supported by the Young and Key Teacher in Colleges and Universities of Henan Province (2011GGJS-163), and the Natural Science Research Program of Education Department of Henan Province (13A180107).

语种：英文

外文关键词：silkworm; GRP78; heat shock; starvation; bacterial challenge

摘要：GRP78 (78 kDa glucose-regulated protein), also known as BiP (immunoglobulin heavy-chain-binding protein), is an essential regulator of endoplasmic reticulum (ER) homeostasis because of its multiple functions in protein folding, ER calcium binding, and controlling of the activation of transmembrane ER stress sensors. In this report, we cloned the full-length cDNA of GRP78 from silkworm Bombyx mori (BmGRP78). It is 2645 bp, including an open reading frame (ORF) of 1977 bp encoding a polypeptide of 658 amino acids. We sequenced the ORF sequence from genomic DNA, and found only one intron (104 bp) existed in Bmgrp78 gene structure. The deduced amino acid sequence of Bmgrp78 carries the ER retention signal KDEL at its C-terminus and is highly homologous to GRP78 of Fenneropenaeus chinensis (83.59%) and Homo sapiens (80.27%). RT-PCR analysis shows that Bmgrp78 is ubiquitously expressed in tissues of silkworm. Heat shock over 35A degrees C notably enhanced the expression of Bmgrp78 in head tissues. In response to starvation, the transcript level of Bmgrp78 in head tissues was 2.8-fold (at WS stage) and 3.2-fold (at SD1 stage) higher than the control level, but it remained stable in the midgut tissues. After silkworms were challenged by bacteria, the relative expression level of Bmgrp78 in midgut was up-regulated and reached maximal level at 24 hour after injection, and remained higher level than that of controls at about 48 hour post challenge. We infer that BmGRP78 may play important roles in chaperoning, protein folding and immune function of silkworm.