Over-expression GbERF2 transcription factor in tobacco enhances brown spots disease resistance by activating expression of downstream genes.
Over-expression GbERF2 transcription factor in tobacco enhances brown spots disease resistance by activating expression of downstream genes.
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DOI：
10.1016/j.gene.2006.12.019
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发表时间：
2007-04
期刊：
影响因子：
3.5
通讯作者：
K. Zuo;J. Qin;Jing-ya Zhao;H. Ling;Lida Zhang;Youfang Cao;K. Tang
中科院分区：
文献类型：
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作者：
K. Zuo;J. Qin;Jing-ya Zhao;H. Ling;Lida Zhang;Youfang Cao;K. Tang
ERF转录因子可以结合GCC盒子或非GCC顺式元件来调节生物和非生物胁迫反应。本研究利用抑制减法杂交技术，从大丽花黄萎病侵袭后的海岛棉中克隆了ERF转录因子基因GbERF2。GbERF2 cDNA全长1143 bp，开放阅读框597 bp。GbERF2基因组序列包含一个515bp的内含子。该基因编码198个氨基酸的预测多肽，分子量为22.5 kDa，计算pI为9.82。GbERF2蛋白具有高度保守的ERF结构域，其核苷酸和氨基酸序列与其他ERF植物蛋白同源性较低。RNA印迹显示，GbERF2在不同组织中均有组成性表达，但在叶片中表达量较高。当植物暴露于外源乙烯处理和大鲵感染时，GbERF2转录本的高水平迅速积累，而在盐、冷、干旱和水分胁迫下，GbERF2转录本的积累较少。相比之下，GbERF2转录本在外源脱落酸（ABA）处理下呈下降趋势。转GbERF2基因的烟草植株组成性地积累了较高水平的致病相关基因转录物，如PR-1b、PR2和PR4。转基因烟草对真菌侵染的抗性增强。然而，对丁香假单胞菌感染的抗性。烟草没有得到改善。这些结果表明，GbERF2在棉花对乙烯胁迫和真菌侵害的响应中起着重要作用。
ERF transcription factors can bind GCC boxes or non-GCC cis elements to regulate biotic and abiotic stress responses. Here, we report that an ERF transcription factor gene (GbERF2) was cloned by suppression subtraction hybridization from sea-island cotton after Verticillium dahliae attack. The GbERF2 cDNA has a total length of 1143 bp with an open reading frame of 597 bp. The genomic sequence of GbERF2 contains an intron of 515 bp. The gene encodes a predicated polypeptide of 198 amino acids with a molecular weight of 22.5 kDa and a calculated pI of 9.82. The GbERF2 protein has a highly conserved ERF domain while the nucleotide and amino acid sequences have low homology with other ERF plant proteins. An RNA blot revealed that GbERF2 is constitutively expressed in different tissues, but is higher in the leaves. High levels of GbERF2 transcripts rapidly accumulated when the plants were exposed to exogenous ethylene treatment and V. dahliae infection, while there was only a slight accumulation in response to salt, cold, drought and water stresses. In contrast, GbERF2 transcripts declined in response to exogenous abscisic acid (ABA) treatment. GbERF2 transgenic tobacco plants constitutively accumulated higher levels of pathogenesis-related gene transcripts, such as PR-1b, PR2 and PR4. The resistance of transgenic tobacco to fungal infection by Alternaria longipes was enhanced. However, the resistance to bacterial infection by Pseudomonas syringae pv. tabaci was not improved. These results show that GbERF2 plays an important role in response to ethylene stress and fungal attack in cotton.