Wang Jiali, Dai Yujie, Li Xiaodan, Zhu Liya, Liu Shixia, He Yeling, Zhang Jing, Song Fengming, Li Dayong
Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Key Laboratory of Biology and Ecological Regulation of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, PR China.
Ministry of Agricultural and Rural Affairs Key Laboratory of Molecular Biology of Crop Pathogens and Insect Pests, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, PR China; Zhejiang Key Laboratory of Biology and Ecological Regulation of Crop Pathogens and Insects, Institute of Biotechnology, Zhejiang University, Hangzhou 310058, PR China; Key Laboratory of Marine Biotechnology of Zhejiang Province, School of Marine Sciences, Ningbo University, Ningbo 315211, PR China.
Int J Biol Macromol. 2025 Apr;301:140466. doi: 10.1016/j.ijbiomac.2025.140466. Epub 2025 Jan 28.
The evolutionarily conserved and multifunctional B-cell lymphoma2 (Bcl2)-associated athanogene proteins (BAGs), serving as co-chaperone regulators, play a pivotal role in orchestrating plant stress responses. In this study, the possible involvement of tomato SlBAG genes in resistance to Botrytis cinerea was examined. The SlBAG genes respond with different expression change patterns to B. cinerea and defense signaling hormones. SlBAG proteins are individually differentially localized to the nucleus, mitochondria, cytoplasm, endoplasmic reticulum (ER), or vacuole. Silencing of SlBAG5 enhanced immunity to B. cinerea, while overexpression weakened it, affecting Botrytis-induced JA/ET defense gene expression and JA levels. Chitin-induced ROS burst and expression of PTI marker genes SlPTI5 and SlLRR22 were strengthened in SlBAG5-silenced plants but were weakened in SlBAG5-overexpressing plants (SlBAG5-OE) plants. SlBAG5 interacts with BON1 ASSOCIATED PROTEIN 1 (SlBAP1) through its BAG domain, and the stability of SlBAP1 depends on the presence of SlBAG5. Silencing of SlBAP1 conferred increased resistance to B. cinerea through increased expression of JA/ET signaling and defense genes. SlBAP1 functions by recruiting and boosting SlCAT3 activity to remove HO. The findings suggest that SlBAG5 suppresses tomato immunity to B. cinerea by stabilizing SlBAP1, which modulates ROS scavenging and acts as a negative regulator of immunity.
进化上保守且多功能的B细胞淋巴瘤2（Bcl2）相关热激蛋白（BAG）作为共伴侣调节因子，在协调植物应激反应中起关键作用。在本研究中，检测了番茄SlBAG基因在对灰霉病菌抗性中的可能作用。SlBAG基因对灰霉病菌和防御信号激素有不同的表达变化模式响应。SlBAG蛋白分别定位于细胞核、线粒体、细胞质、内质网（ER）或液泡。SlBAG5基因沉默增强了对灰霉病菌的免疫力，而过表达则削弱了免疫力，影响了灰霉病菌诱导的茉莉酸/乙烯（JA/ET）防御基因表达和JA水平。几丁质诱导的活性氧（ROS）爆发以及模式识别受体触发免疫（PTI）标记基因SlPTI5和SlLRR22在SlBAG5基因沉默的植株中增强，但在SlBAG5过表达（SlBAG5-OE）植株中减弱。SlBAG5通过其BAG结构域与BON1相关蛋白1（SlBAP1）相互作用，且SlBAP1的稳定性依赖于SlBAG5的存在。SlBAP1基因沉默通过增加JA/ET信号和防御基因的表达赋予对灰霉病菌更高的抗性。SlBAP1通过招募和增强SlCAT3活性以清除过氧化氢发挥作用。这些发现表明，SlBAG5通过稳定SlBAP1抑制番茄对灰霉病菌的免疫力，SlBAP1调节ROS清除并作为免疫的负调节因子。
