Chen Hongfeng, Su Shunyu, Yang Shumin, Zhao Tianqi, Tang Ping, Luo Qiong, Zhong Yuanyuan, Yang Jing
State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Yunnan Agricultural University, Kunming 650201, China.
Key Laboratory of Agro-Biodiversity and Pest Management of Ministry of Education, Yunnan Agricultural University, Kunming 650201, China.
Plant Physiol. 2024 Oct 1;196(2):1042-1063. doi: 10.1093/plphys/kiae364.
C2H2 zinc effectors are a class of pathogen proteins that play a dual role in plant-pathogen interactions, promoting pathogenicity and enhancing plant defense. In our previous research, we identified Magnaporthe oryzae Systemic Defense Trigger 1 (MoSDT1) as a C2H2 zinc effector that activates rice (Oryza sativa) defense when overexpressed in rice. However, its regulatory roles in pathogenicity and defense require further investigation. In this study, we generated an MoSDT1 overexpressing strain and 2 knockout strains of M. oryzae to assess the impact of MoSDT1 on pathogenicity, rice defense, and phenotypic characteristics. Our analyses revealed that MoSDT1 substantially influenced vegetative growth, conidia size, and conidiation, and was crucial for the virulence of M. oryzae while suppressing rice defense. MoSDT1 localized to the nucleus and cytoplasm of rice, either dependent or independent of M. oryzae delivery. Through RNA-seq, scRNA-seq, and ChIP-seq, we identified that MoSDT1 modulates rice defense by regulating the phosphorylation and ubiquitination of various rice signaling proteins, including transcription factors, transcription repressors, kinases, phosphatases, and the ubiquitin system. These findings provide valuable insights into the regulatory mechanisms of C2H2 zinc finger effector proteins and offer important foundational information for utilizing their target genes in disease resistance breeding and the design of targets for disease management.
C2H2锌效应因子是一类病原体蛋白，在植物与病原体的相互作用中发挥双重作用，既促进致病性又增强植物防御。在我们之前的研究中，我们鉴定出稻瘟病菌系统防御触发因子1（MoSDT1）是一种C2H2锌效应因子，当在水稻中过表达时可激活水稻（Oryza sativa）的防御。然而，其在致病性和防御中的调控作用仍需进一步研究。在本研究中，我们构建了一个MoSDT1过表达菌株和两个稻瘟病菌基因敲除菌株，以评估MoSDT1对致病性、水稻防御和表型特征的影响。我们的分析表明，MoSDT1对营养生长、分生孢子大小和产孢有显著影响，对稻瘟病菌的毒力至关重要，同时抑制水稻防御。MoSDT1定位于水稻的细胞核和细胞质中，无论是否依赖稻瘟病菌的传递。通过RNA测序、单细胞RNA测序和染色质免疫沉淀测序，我们确定MoSDT1通过调节各种水稻信号蛋白的磷酸化和泛素化来调节水稻防御，这些信号蛋白包括转录因子、转录抑制因子、激酶、磷酸酶和泛素系统。这些发现为C2H2锌指效应蛋白的调控机制提供了有价值的见解，并为在抗病育种中利用其靶基因以及病害管理靶点设计提供了重要的基础信息。
