Silencing of SlMYB50 affects tolerance to drought and salt stress in tomato
Silencing of SlMYB50 affects tolerance to drought and salt stress in tomato
复制标题
SlMYB50 沉默影响番茄对干旱和盐胁迫的耐受性
DOI：
10.1016/j.plaphy.2022.10.026
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发表时间：
2022-11-08
影响因子：
6.5
通讯作者：
Hu, Zongli
中科院分区：
文献类型：
--
作者：
Chen, Yanan;Feng, Panpan;Hu, Zongli
高盐度和干旱胁迫通常会导致植物产生包括过氧化氢(H_2O_2)和超氧化物歧化酶(O-2(-))在内的ROS，它们干扰植物的生长并影响作物产量。MYB家族的转录因子参与了对生物和非生物胁迫的响应。在这里，我们分离了R2R3-MYB转录因子基因SLMYB50，发现沉默SLMYB50增加了对PEG6000、甘露醇和盐的抗性。此外，转基因番茄在高盐和干旱胁迫下的抗逆性增强。胁迫处理后，SLMYB50-RNAi系的相对含水量、叶绿素含量(固碳关键)和根系活力均高于野生型(WT)。失水率、相对电导率和丙二醛(作为细胞壁破裂的标志)则相反。在干旱胁迫条件下，SLMYB50沉默的品系比对照表现出更少的过氧化氢和更少的臭氧积累，以及更高的CAT酶活性。值得注意的是，胁迫处理后，与野生型相比，SLMYB50沉默的品系中叶绿素合成相关基因、类黄酮合成相关基因、类胡萝卜素相关基因、抗氧化酶相关基因和ABA生物合成相关基因的表达水平均上调。用双荧光素酶报告系统验证了SLMYB50能与CHSi启动子结合。综上所述，本研究确定了SLMYB50在调节干旱和耐盐性方面的重要作用。
High salinity and drought stresses often cause plants to produce ROS, including hydrogen peroxide (H2O2) and superoxide (O-2(-)), which interfere with plant growth and affect crop yield. The transcription factors of the MYB family are involved in responses to biotic and abiotic stresses. Here, we isolated the R2R3-MYB transcription factor gene SlMYB50 and found that silencing of SlMYB50 increased resistance to PEG 6000, mannitol and salt. In addition, the resistance of transgenic tomatoes increased under high salt and drought stress. After stress treatment, the relative water content, chlorophyll content (critical for carbon fixation) and root vitality of the SlMYB50-RNAi lines were higher than those of the wild-type (WT). The opposite was true the water loss rate, relative conductivity, and MDA (as a sign of cell wall disruption). Under drought stress conditions, SlMYB50-silenced lines exhibited less H2O2 and less OZ accumulation, as well as higher CAT enzyme activity, than were exhibited by the WT. Notably, after stress treatment, the expression levels of chlorophyll-synthesis-related, flavonoid-synthesis-related, carotenoid-related, antioxidant-enzyme-related and ABA-biosynthesis-related genes were all upregulated in SlMYB50-silenced lines compared to those of WT. A dual-luciferase reporter system was used to verify that SlMYB50 could bind to the CHSI promoter. In summary, this study identified essential roles for SlMYB50 in regulating drought and salt tolerance.