中华绒螯蟹热激蛋白90基因内含子的克隆与界定

Cloning and Characterization of Heat Shock Protein 90 Gene Introns in the Chinese Mitten Crab Eriocheir sinensis

热激蛋白家族中分子量为90kDa的热激蛋白(HSP90)是真核细胞胞质中最丰富和高度保守的蛋白质之一.HSP90作为一种重要的分子伴侣,广泛参与细胞的激素信号通路、细胞周期调控以及细胞发育等重要的生理过程;内含子(intron)是基因中的非编码DNA片段,参与基因的组织特异性表达、蛋白质变异、基因转录等多种生物学过程.本文通过PCR扩增得到了中华绒螯蟹(Eriocheir sinensis)HSP90(命名为EsHSP90)的3个内含子序列(分别为296 bp、140 bp和173bp),内含子1和内含子3的剪接符合GT-AG规律,而内含子2不遵循GT-AG或AT-AC规律.EsHSP90的DNA序列全长为3 126 bp.序列比对分析显示EsHSP90与已知甲壳动物的HSP90具有高于80%的序列相似度.

The heat shock protein 90（HStX）0） is a highly conserved molecular chaperone particularly important in the maturation of a diverse set of proteins that regulating key steps in various biological processes, such as hormone signaling pathways in cells, cell cycle regulation, cell growth and development, etc.. Introns are the noncoding DNA fragments, which are involved in variety of biological activities ,such as regulating gene expression ,protein alternative splicing and gene tran- scription,etc.. Based on PCR technique,the three introns （296 bp, 141 bp and 173 bp）of a HSPgO gene（ named as EsHSPgO）were identified and characterized from the Chinese mitten crab Eriocheir sinensis. EsHSPgO gene had two GT-AG type introns（ intron-1 and intron-3 ）. While exon-intron splicing for intron-2 did not follow the GT-AG or AT-AC rules. The full-length DNA of EsHSPgO is 3,126 bp in size and contains an open reading frame of 2,157 bp which encodes a 718 amino acid polypeptide（ 82.85 kDa）with HSPgO family signatures and ATP binding domain. Sequence alignment shows that the full-length DNA sequence of EsHSP90 shared more than 80% identity with HSP90 sequences reported in crustaceans.