鲍思元 刘卫东 李冬波

摘要[目的]对水稻OsARAB1基因进行电子克隆，并对其进行生物信息学分析。[方法]以NP 174188.1为查询探针，通过电子克隆获得OsARAB1基因全长cDNA，用生物信息学软件对其核苷酸序列和蛋白质序列进行生物信息学分析。[结果]获得了OsARAB1基因全长cDNA，基因编码区序列（CDS）全长1 086 bp。电子定位于第五染色体基因组序列NC 008398.2核苷酸序列6 769 813～6 773 213 bp区域。OsARAB1蛋白属于亲水性的胞外蛋白，比较稳定，偏碱性。二级结构以α螺旋和无规则卷曲为主。具有2个功能结构域：SGNH水解酶型酯酶、GDSL脂肪酶。有21个磷酸化位点、7个糖基化位点。推定的活性位点的氨基酸残基为Ser34、Gly107、Asn167、Asp333、His336。與玉米酯酶亚型B4FM12亲缘关系最近。OsARAB1基因的表达对水稻的发育和形态发生起重要作用，与水稻抗稻瘟病有关。[结论]该研究为用试验方法克隆该基因和功能鉴定奠定了基础。

关键词水稻；脂肪酶；生物信息学；氨基酸序列；OsARAB1基因

中图分类号S188；Q943.2文献标识码A文章编号0517-6611（2015）31-038-07

In Silico Cloning and Bioinformatics Analysis of ARAB1like Gene from Rice

BAO Siyuan1， LIU Weidong2， LI Dongbo3

（1. College of Basic Medical， Hubei University of Science and Technology， Xianning， Hubei 437100； 2. School of Nuclear Technology and Chemistry & Biology， Hubei University of Science and Technology， Xianning， Hubei 437100； 3. Horticultural Research Institute， Guangxi Academy of Agricultural Sciences， Nanning， Guangxi 530007）

Abstract [Objective] The aim of this study was to clone the OsARAB1 gene from rice in silico， and to analyze its biological information. [Method] Using NP 174188.1 as the probe， the fulllength cDNA sequence of OsARAB1 gene was obtained by in silico cloning； its nucleotide sequence and protein were analyzed by bioinformatics softwares. [Result] The full length cDNA of OsARAB1 gene was obtained， and the sequence of the gene encoding region （CDS） was 1086 bp， encoded a protein of 361 amino acid residues. OsARAB1 gene was located in the genome sequence NC 008398.2（ 6 769 813—6 773 213 bp region） by in silico mapping. OsARAB1 protein belonged to hydrophilic extracellular protein， and it was relatively stable， partial alkaline. The secondary structure of this protein was mainly composed of alpha helix and random coil. It belonged to SGNH lipase， and had 21 phosphorylation sites， 7 OβGlcNAc glycosylation sites. The putative active sites of amino acid residues were Ser34， Gly107， Asn167， Asp333， His336. It had the closest relationship with the esterase isoform B4FM12 from maize. The expression of OsARAB1 gene played an important role in development and morphogenesis of rice， and had a relationship with the rice blast resistance. [Conclusion] This study laid a foundation for OsARAB1 gene clone and functional identification using experimental method.

Key words Rice； Lipase； Bioinformatics； Amino acid sequence； OsARAB1 gene

脂肪酶（EC 3.1.1.3）是一类水解酶，广泛分布于植物、动物、微生物中，催化多种生化反应，包括水解、醇解、酸解、酯化、酯交换、氨解。GDSL脂肪酶是一类重要的脂肪酶家族，具有一个GDSL模体（GXSXXXXG），活性位点的丝氨酸靠近多肽链的N端[1-2]；而GXSXG模体的α/β折叠型水解酶超家族活性位点的丝氨酸位于多肽链的中间[3]。具有5块高度保守的同源序列[1]，由于4个高度保守的残基：丝氨酸、甘氨酸、天冬氨酰、组氨酸分别位于块I、块II、块III、块V，GDSL脂肪酶被建议更名为“SGNH-hydrolases”[4]。GDSL脂肪酶的催化位置易于变构，因此该酶具有广泛的底物特异性[5]。然而，大多数GDSL脂肪酶的天然底物仍未知。……