School of Plant Sciences and Food Security, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel.
College of Life Science and Technology, Wuhan Polytechnic University, Wuhan City, Hubei Province, China.
Nat Commun. 2021 Apr 12;12(1):2166. doi: 10.1038/s41467-021-22436-1.
Crh proteins catalyze crosslinking of chitin and glucan polymers in fungal cell walls. Here, we show that the BcCrh1 protein from the phytopathogenic fungus Botrytis cinerea acts as a cytoplasmic effector and elicitor of plant defense. BcCrh1 is localized in vacuoles and the endoplasmic reticulum during saprophytic growth. However, upon plant infection, the protein accumulates in infection cushions; it is then secreted to the apoplast and translocated into plant cells, where it induces cell death and defense responses. Two regions of 53 and 35 amino acids are sufficient for protein uptake and cell death induction, respectively. BcCrh1 mutant variants that are unable to dimerize lack transglycosylation activity, but are still able to induce plant cell death. Furthermore, Arabidopsis lines expressing the bccrh1 gene exhibit reduced sensitivity to B. cinerea, suggesting a potential use of the BcCrh1 protein in plant immunization against this necrotrophic pathogen.
Crh 蛋白催化真菌细胞壁中几丁质和葡聚糖聚合物的交联。在这里，我们表明来自植物病原菌 Botrytis cinerea 的 BcCrh1 蛋白作为细胞质效应子和植物防御的激发子。BcCrh1 在腐生生长过程中定位于液泡和内质网中。然而，在植物感染时，该蛋白在侵染垫中积累；然后分泌到质外体并易位到植物细胞中，在那里诱导细胞死亡和防御反应。53 个和 35 个氨基酸的两个区域分别足以进行蛋白摄取和细胞死亡诱导。无法二聚化的 BcCrh1 突变体变体缺乏转糖基化活性，但仍能够诱导植物细胞死亡。此外，表达 bccrh1 基因的拟南芥系表现出对 B. cinerea 的敏感性降低，表明 BcCrh1 蛋白在植物免疫接种针对这种坏死性病原体中的潜在用途。
