《植物生理学报》 2017, 53(1): 52-62

巴西橡胶树α-微管蛋白HbTUA2基因的克隆、表达及生物信息学分析

杨洪, 邓治, 刘辉, 代龙军, 李德军^*

中国热带农业科学院橡胶研究所, 农业部橡胶树生物学与遗传资源利用重点实验室, 海南儋州571737

通信作者：李德军；E-mail: djli.rricatas@gmail.com

摘　要：

微管蛋白是微管的重要组成部分, 参与维持细胞骨架的稳定及延伸。本研究采用RT-PCR和RACE技术从巴西橡胶树(Hevea brasiliensis)中克隆到一个α-微管蛋白基因, 命名为HbTUA2 (GenBank登录号: KX809698)。该基因cDNA全长1 940 bp, 其中开放阅读框1 353 bp, 编码含450个氨基酸残基的蛋白质序列。HbTUA2与其他植物TUA蛋白高度同源, 具有TUA蛋白家族保守的GTP结合位点和转录后调控片段。基因结构分析表明, HbTUA2具有4个外显子和3个内含子, 内含子外显子剪切符合“GT-AG”规则。荧光定量PCR分析表明, HbTUA2在巴西橡胶树叶片、雌花、雄花、茎尖、树皮及胶乳等组织中均有表达, 在雌花中表达量最高, 其次是茎尖和雄花, 在叶片、树皮和胶乳中表达量较低。此外, HbTUA2的表达还受高盐、干旱、低温、过氧化氢(H₂O₂)、乙烯利和茉莉酸甲酯(MeJA)调控, 表明HbTUA2可能参与巴西橡胶树乙烯和茉莉酸信号途径及逆境胁迫应答过程。

关键词：橡胶树; α-微管蛋白; 逆境胁迫; 表达分析

收稿：2016-09-14   修定：2016-10-28

资助：国家自然科学基金(31570684、31270651和31200514)和中国热带农业科学院橡胶研究所基本科研业务费专项(1630022015003)。

Cloning, expression and bioinformatics analysis of HbTUA2 gene in Hevea brasiliensis (rubber tree)

YANG Hong, DENG Zhi, LIU Hui, DAI Long-Jun, LI De-Jun^*

Key Laboratory of Biology and Genetic Resources of Rubber Tree, Ministry of Agriculture, Rubber Research Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou, Hainan 571737, China

Corresponding author: LI De-Jun; E-mail: djli.rricatas@gmail.com

Abstract:

As the major proteins assemble into microtubules, tubulins are involved in maintaining the stability and elongation of the cytoskeleton. Here we report an α-tubulin gene (TUA), HbTUA2, from Hevea brasiliensis by reverse transcription-polymerase chain reaction (RT-PCR) and rapid-amplification of cDNA ends (RACE). The HbTUA2 cDNA sequence is 1 940 bp in length, and contains an open reading frame (ORF) of 1 353 bp encoding a polypeptide of 450 residues. HbTUA2 owned the typical conserved GTP binding site and a post transcriptional active domain of TUA and showed high homology with TUA proteins from other plants. Genomic organization analysis showed that HbTUA2 contained four exons and three introns, and all intron/exon boundaries were in accordance with the GT/AG rule. Real-time PCR results showed that HbTUA2 was expressed in leaf, flower, stem tip, bark and latex of Hevea brasiliensis, with the highest expression in female flower and the lowest expression in latex. Moreover, the expression of HbTUA2 was regulated by NaCl, drought, low temperature, hydrogen peroxide (H₂O₂), ethephon (ET) and methyl jasmonate (MeJA) treatments. All these results suggested that HbTUA2 might play important roles in stresses responses as well as ET and JA signals in Hevea brasiliensis.

Key words: Hevea brasiliensis; α-tubulin; stresses responses; expression analysis