《植物生理学报》 2010, 46(7): 671-676

小麦富含亮氨酸重复(LRR)蛋白基因TaLRI1 的克隆及其特征分析

孟凡荣¹, 冉彩华¹, 刘浩¹, 陈雷², 李金花², 尹钧², 李永春^2,*

河南农业大学1 生命科学学院, 2 国家小麦工程技术研究中心, 郑州450002

通信作者：李永春；E-mail: yongchunli71@yahoo.com.cn；Tel: 0371-63558215

摘　要：

在水分胁迫反应基因表达谱分析的基础上, 采用 RACR 技术, 从 ‘ 洛旱 2 号 ’ 小麦中克隆了一个编码富含亮氨酸蛋白 的 cDNA 全长, 命名为 TaLRI1。序列分析显示, TaLRI1 的 cDNA 全长为 2 657 bp (GenBank 登录号为 GU593320), 其中 5'- 非翻译区 47 bp, 3'- 非翻译区 1 314 bp, 开放阅读框 1 296 bp, 可编码 431 个氨基酸。进一步分析显示, TaLRI1 基因编码的蛋 白具有典型的富含亮氨酸 N 末端保守域和富含亮氨酸的核酸酶抑制因子保守域, 该蛋白为弱酸性蛋白, 等电点为 5.69, 无 明显的疏水 / 亲水区域。三维结构预测显示, TaLRI1 蛋白以 α- 螺旋、β-折叠和无规卷曲为骨架, 可形成弧状的螺线管结构 以及一对侧臂凸起。RT-PCR 分析表明, 水分胁迫过程中, TaLRI1 基因在根系中的表达量呈先升高后降低的趋势, 以胁迫 处理12 h的表达量最高, 推测该基因在水分胁迫反应过程中发挥重要功能。

关键词：小麦; TaLRI1; 基因克隆; 序列特征

收稿：2010-03-01   修定：2010-05-31

资助：国家转基因生物新品种培育科技重大专项(2009ZX08002-011B)和河南省教育厅自然科学研究计划(2009A210012)。

Cloning and Characterization of a Leucine-Rich Repeat (LRR) Protein Gene TaLRI1 in Wheat (Triticum aestivum L.)

MENG Fan-Rong¹, RAN Cai-Hua¹, LIU Hao¹, CHEN Lei², LI Jin-Hua², YIN Jun², LI Yong-Chun^2,*

¹College of Life Sciences, ²National Engineering Research Centre for Wheat, Henan Agricultural University, Zhengzhou 450002, China

Corresponding author: LI Yong-Chun; E-mail: yongchunli71@yahoo.com.cn; Tel: 0371-63558215

Abstract:

Based on our previous study on the water stress responsive transcriptomes in wheat, a full-length cDNA, encoding a leucine-rich repeat (LRR) protein, was cloned via rapid amplification of cDNA ends (RACE) technology from the wheat (Triticum aestivum) cultivar ‘Luohan 2’, which was termed as TaLRI1 with the GenBank accession No. of GU593320. Sequence analysis showed that the full-length cDNA of TaLRI1 was 2 657 bp, which including 47 bp 5' UTR, 1 314 bp 3' UTR and 1 296 bp open reading frame (ORF) encoding 431 amino acid residues. The further analysis indicated that a typical LRR N-terminal domain and a LRR ribonuclease inhibitor (LRR_RI) domain was included in the deduced amino acid sequence of TaLRI1. The putative TaLRI1 protein was acidulous with a pI of 5.69 and obvious hydrophobic or hydrophilic domains were not found in it. The 3D structure prediction showed that the TaLRI1 was constructed by α-helixes, β-strands and random loops, and could wrap around in a curved, right-handed solenoid with a pair of extended side arms. The expression pattern of TaLRI1 in roots under water stress was analyzed via RT-PCR and the results showed that the gene was gradually induced with the water-stress accumulation, while its expression level decreased after 12h after water-stress treatment, which indicated that the TaLRI1 played important roles during the water-stress responding in wheat.

Key words: wheat; TaLRI1; gene cloning; sequential characterization