组蛋白去乙酰化酶CfSnt2调控果生刺盘孢生长发育和致病力

炭疽病是油茶Camellia oleifera的重要病害,该病害的优势致病菌是刺盘孢属Colletotrichum的果生刺盘孢C. fructicola,在全国的油茶产区普遍发生。我们前期发现组蛋白乙酰转移酶CfGcn5调控油茶果生刺盘孢的生长发育和致病过程,但组蛋白去乙酰化酶在该病菌中的生物学功能尚不清楚。本研究以组蛋白去乙酰化酶CfSnt2为研究对象,利用反向遗传学的方法,通过对野生型、CfSNT2基因敲除突变体及互补菌株的生物学表型进行比较分析,发现CfSNT2基因敲除突变体的菌丝生长速率明显减缓、分生孢子的产量显著减少、附着胞形成率降低、对细胞壁胁迫剂的响应异常,同时对油茶致病力显著减弱。以上现象说明CfSnt2调控果生刺盘孢的生长、产孢、附着胞的形成、对细胞壁完整性胁迫剂的耐受性及致病力。

Histone deacetylase CfSnt2 regulates the growth,development and pathogenicity of Colletotrichum fructicola

Anthracnose is one of the most important diseases occurring on Camellia oleifera. The dominant pathogen causing the disease is Colletotrichum fructicola which is common in C. oleifera producing areas all over the country. Previous study recognized that the histone acetyltransferase CfGcn5 regulated growth, development and pathogenicity of C. fructicola, but the functions of histone deacetylases remain unknown. In this study, the reverse genetics method was adopted to comparatively analyze the biological phenotypes of wide-type, CfSNT2 gene knockout mutant and its complementary strains of C. fructicola. It was found that the CfSNT2 gene knockout mutant showed decrement of mycelial growth rate, and conidial and appressorial formation rate, and abnormal response to cell wall integrity stress agents, resulting in decrease of pathogenicity to C. oleifera. The findings show that CfSnt2 regulates the mycelial growth, conidial and appressorial formation, tolerance to cell wall integrity stress agents, and pathogenicity of C. fructicola.