OsbHLH148, a basic helix‐loop‐helix protein, interacts with OsJAZ proteins in a jasmonate signaling pathway leading to drought tolerance in rice

作者：Ju‐Seok Seo, Joungsu Joo, Min‐Jeong Kim, Yeon-Ki Kim, Baek Hie Nahm, Sang Ik Song, Jong‐Joo Cheong, Jong Seob Lee, Ju‐Kon Kim, Yang Do Choi · 发表于：The Plant Journal · 年份：2010 · DOI：10.1111/j.1365-313x.2010.04477.x · 被引用次数：611 · 研究领域：Insect-Plant Interactions and Control、Plant Parasitism and Resistance、Plant Stress Responses and Tolerance

Jasmonates play important roles in development, stress responses and defense in plants. Here, we report the results of a study using a functional genomics approach that identified a rice basic helix-loop-helix domain gene, OsbHLH148, that conferred drought tolerance as a component of the jasmonate signaling module in rice. OsbHLH148 transcript levels were rapidly increased by treatment with methyl jasmonate (MeJA) or abscisic acid, and abiotic stresses including dehydration, high salinity, low temperature and wounding. Transgenic over-expression of OsbHLH148 in rice confers plant tolerance to drought stress. Expression profiling followed by DNA microarray and RNA gel-blot analyses of transgenic versus wild-type rice identified genes that are up-regulated by OsbHLH148 over-expression. These include OsDREB and OsJAZ genes that are involved in stress responses and the jasmonate signaling pathway, respectively. OsJAZ1, a rice ZIM domain protein, interacted with OsbHLH148 in yeast two-hybrid and pull-down assays, but it interacted with the putative OsCOI1 only in the presence of coronatine. Furthermore, the OsJAZ1 protein was degraded by rice and Arabidopsis extracts in the presence of coronatine, and its degradation was inhibited by MG132, a 26S proteasome inhibitor, suggesting 26S proteasome-mediated degradation of OsJAZ1 via the SCF(OsCOI1) complex. The transcription level of OsJAZ1 increased upon exposure of rice to MeJA. These results show that OsJAZ1 could act as a transcrip...