板栗疫病菌cpnat基因的功能分析

Function Analysis of cpnat Gene in Cryphonectria parasitica

赖氨酸乙酰化是一种重要的蛋白质翻译后修饰,广泛参与多种生命过程的调节。目前,赖氨酸乙酰化修饰在植物病原真菌——板栗疫病菌中的功能和调节机制尚无报道。本研究克隆了板栗疫病菌的编码乙酰转移酶的cpnat基因,成功构建了cpnat基因的缺失突变体△cpnat,与野生型菌株相比,板栗疫病菌cpnat基因缺失株生长速率不变,气生菌丝变浓密,菌丝末端分支变多,色素明显减少,产孢能力显著降低,致病力也降低。cpnat基因的缺失并不影响参与信号传导途径的cpga1、cpgb1、cpmk1、cpmk2和ste12基因的转录水平,表明其对色素、产孢和致病力的调控是通过尚未被发现的途径实现的。本研究结果为揭示乙酰化修饰在病原真菌中的功能提供了新的知识。

Lysine acetylation plays an important role in protein post-translational modification.It was involved in many biological processes.At present,the function and regulatory mechanism of lysine acetylation in plant pathogenic fungus,Cryphonectria parasitica,have not been reported.In this study,the gene cpnat of C.parasitica,which encodes acetyltransferase,was cloned.The cpnat gene knockout strain△cpnat was constructed successfully.Compared with the wild-type strain,cpnat null mutants showed no difference in growth rate.However,△cpnat showed that a phenotype of the aerial hyphae Wie was dense,the end branches of the hyphae were more numerous,the pigment was significantly reduced and lower level of sporulation and a marked decrease in virulence.Deletion of the cpnat gene did not affect the transcriptional levels of the cpga1,cpgb1,cpmk1,cpmk2,and ste12 genes involved in signaling pathways.These results indicate that CpNat plays an important role in the regulation of sporulation,pigmentation,mycelium and virulence through a currently not yet identified pathway.This study provides a novel knowledge for understanding of the role of acetylation in pathogenic fungi.