Niu Xianyu, Yang Guijing, Lin Hui, Liu Yao, Li Ping, Zheng Aiping
College of Agronomy, Sichuan Agricultural University, Chengdu, China.
Rice Research Institute, Sichuan Agricultural University, Chengdu, China.
Front Microbiol. 2021 Aug 23;12:684923. doi: 10.3389/fmicb.2021.684923. eCollection 2021.
The necrotrophic phytopathogen () is a fungus that causes disease in a wide range of plant species. Fungal genomes encode abundant, small cysteine-rich (SCR) secreted proteins, and the probable importance of these to pathogenesis has been highlighted in various pathogens. However, there are currently no reports of an SCR-secreted protein with evidential elicitor activity. In this study, the molecular function of 10 SCR-secreted protein genes from was explored by agroinfiltration into () leaves, and a novel SCR protein RsSCR10 was identified that triggered cell death and oxidative burst in tobacco. RsSCR10 comprises 84 amino acids, including a signal peptide (SP) of 19 amino acids that is necessary for RsSCR10 to induce tobacco cell death. Elicitation of cell death by RsSCR10 was dependent on Hsp90 but not on RAR1, proving its effector activity. Two cysteine residues have important effects on the function of RsSCR10 in inducing cell death. Furthermore, RsSCR10 showed cross-interaction with five rice molecules, and the inferred functions of these rice proteins suggest they are instrumental in how the host copes with adversity. Overall, this study demonstrates that RsSCR10 is a potential effector that has a critical role in AG1 IA-host interactions.
坏死营养型植物病原菌（）是一种能在多种植物物种中引发疾病的真菌。真菌基因组编码大量富含半胱氨酸的小分泌蛋白（SCR），并且这些蛋白在各种病原菌中对致病作用的潜在重要性已得到强调。然而，目前尚无关于具有证据确凿的激发子活性的SCR分泌蛋白的报道。在本研究中，通过农杆菌浸润法将来自的10个SCR分泌蛋白基因导入（）叶片中，探索其分子功能，鉴定出一种新型SCR蛋白RsSCR10，它能在烟草中引发细胞死亡和氧化爆发。RsSCR10由84个氨基酸组成，包括一个19个氨基酸的信号肽（SP），该信号肽是RsSCR10诱导烟草细胞死亡所必需的。RsSCR10引发细胞死亡依赖于Hsp90而非RAR1，证明了其效应子活性。两个半胱氨酸残基对RsSCR10诱导细胞死亡的功能有重要影响。此外RsSCR10与五个水稻分子存在交叉相互作用，并且这些水稻蛋白的推测功能表明它们在宿主应对逆境中发挥作用。总体而言，本研究表明RsSCR10是一种潜在的效应子，在AG1 IA -宿主相互作用中起关键作用。
