指状青霉V-ATP酶H亚基蛋白的功能

目的：通过基因干扰和过表达技术，研究V-ATP酶H亚基（V-ATPase membrane subunit H，VMAH）蛋白在柑橘绿霉病菌指状青霉生长中的生理功能，及其作为抗柑橘绿霉病药物作用靶点的可行性。方法：采用菌丝生长法和孢子萌发法，研究沉默和过表达VMAH基因对正常和胁迫条件下指状青霉细胞生长特性的影响。结果：在正常生长条件下，沉默VMAH基因显著抑制了指状青霉菌丝体的生长；而过表达VMAH基因对菌体生长表现出显著促进作用。在不同pH值环境下，沉默VMAH基因显著抑制了指状青霉菌丝的生长，尤其在偏酸性（pH值低于2）和偏碱性（pH值高于8）条件下尤为显著；而过表达VMAH基因在一定程度上促进了菌体菌丝的生长，pH值为6时，其促进作用最显著。与野生株相比，沉默VMAH基因对胞外Ca2＋、Cu2＋、Fe2＋等金属离子胁迫处理较为敏感。VMAH基因沉默菌株对质子泵抑制剂类杀菌剂的敏感性显著增加，尤其V-ATP酶专一性抑制剂巴佛洛霉素A1最为明显；而VMAH基因过表达菌株对质子泵抑制剂类杀菌剂的敏感性显著降低。结论：VMAH在指状青霉生长过程中发挥重要作用，是研发低耐药性柑橘采后杀菌剂的潜在作用靶点。

Function of Penicillium digitatum V-ATPase Subunit H Protein

Objective: This work aims to study the physiological function of V-ATPase membrane subunit H (VMAH) protein in the growth of the citrus green mold fungus Penicillium digitatum and to evaluate its feasibility as a target of anti-citrus green mold drugs through gene interference and overexpression. Methods: The effect of silencing and overexpression of the VMAH gene was investigated on the growth characteristics of P. digitatum cells under normal and stress conditions, as measured by mycelial growth and spore germination. Results: Under normal growth conditions, VMAH silencing significantly inhibited the growth of P. digitatum mycelia, while VMAH overexpression showed a significant promoting effect. Under different pH environments, VMAH silencing significantly inhibited the growth of P. digitatum hyphae, especially under acidic (pH lower than 2) and alkaline (pH higher than 8) conditions, while overexpression of the VMAH gene promoted mycelial growth to a certain extent, especially at pH 6. Compared with the wild-type strain, silencing of the VMAH gene increased the sensitivity to the stress of extracellular Ca2+, Cu2+, Fe2+ and other metal ions and to proton pump inhibitor fungicides, especially the V-ATPase specific inhibitor bafilomycin A1, while VMAH overexpression significantly reduced the sensitivity to proton pump inhibitor fungicides. Conclusion: VMAH plays an important role in the growth of P. digitatum and is a potential target for the development of low-resistant postharvest citrus fungicides.