The calmodulin-binding transcription factor OsCBT suppresses defense responses to pathogens in rice
The calmodulin-binding transcription factor OsCBT suppresses defense responses to pathogens in rice
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DOI：
10.1007/s10059-009-0081-4
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发表时间：
2009-05-01
影响因子：
3.8
通讯作者：
Kim, Min Chul
中科院分区：
文献类型：
--
作者：
Koo, Sung Cheol;Choi, Man Soo;Kim, Min Chul
我们之前从真菌诱变剂处理的水稻悬浮细胞构建的水稻表达文库中分离出编码钙调素（CaM）结合蛋白的OsCBT基因。为了了解水稻中OsCBT的功能，我们分离并鉴定了一个名为OsCBT -1的T-DNA插入突变等位基因。与野生型植物相比，OsCBT -1突变体表现出较低的OsCBT转录本水平，尽管突变体的生长发育迟缓，但形态上没有明显变化。然而，osct -1突变体对两种主要水稻病原菌表现出显著的抗性。研究了稻瘟病菌稻瘟病菌和水稻黄单胞菌的生长情况。Oryzae在osct -1植物中被显著抑制。组织化学分析表明，oscbt-1突变体对真菌病原体的相容性菌株产生了超敏反应。用真菌激发子诱导OsCBT表达。我们还观察到，即使在无病原体的条件下，osct -1突变体的致病相关基因水平也显著增加。综上所述，结果支持了OsCBT可能在植物防御中起负调节作用的观点。
We previously isolated the OsCBT gene, which encodes a calmodulin (CaM)-binding protein, from a rice expression library constructed from fungal elicitor-treated rice suspension cells. In order to understand the function of OsCBT in rice, we isolated and characterized a T-DNA insertion mutant allele named oscbt-1. The oscbt-1 mutant exhibits reduced levels of OsCBT transcripts and no significant morphological changes compared to wild-type plant although the growth of the mutant is stunted. However, oscbt-1 mutants showed significant resistance to two major rice pathogens. The growth of the rice blast fungus Magnaporthe grisea, as well as the bacterial pathogen Xanthomonas oryzae pv. oryzae was significantly suppressed in oscbt-1 plants. Histochemical analysis indicated that the hypersensitive-response was induced in the oscbt-1 mutant in response to compatible strains of fungal pathogens. OsCBT expression was induced upon challenge with fungal elicitor. We also observed significant increase in the level of pathogenesis-related genes in the oscbt-1 mutant even under pathogen-free condition. Taken together, the results support an idea that OsCBT might act as a negative regulator on plant defense.