橡胶树胶孢炭疽菌组蛋白乙酰转移酶CgGCN5调控致病力功能研究

胶孢炭疽菌引起的炭疽病害是造成海南省橡胶减产的主要原因之一。研究该病原菌致病力的分子机制能够为新型防控策略的研发提供理论依据。在橡胶树胶孢炭疽菌中,存在1个编码组蛋白乙酰转移酶的基因CgGCN5。在本研究中,通过同源重组原理及原生质体转化法构建了橡胶树胶孢炭疽菌CgGCN5的敲除突变株和互补菌株,并对其生长、产孢及致病力等表型进行了初步分析。结果表明,与野生型菌株相比,CgGCN5敲除突变株的生长速率、产孢能力均显著下降;并且突变株对橡胶树叶片的致病力也显著下降;进一步分析表明,突变株丧失了对玻璃纸的穿透力。与此同时,互补菌株能够恢复突变株的相应表型。以上结果表明,CgGCN5在调控胶孢炭疽菌的生长及致病力中起重要作用。

Functional Analysis of Histone Acetyl-transferase CgGCN5 in Regulation of Pathogenicity of Colletotrichum gloeosporioides from Hevea brasiliensis

The anthracnose caused by Colletotrichum gloeosporioides is one of the major reasons for resulting in reduction of rubber yield in Hainan. Figuring out the molecular mechanisms of pathogenicity of C. gloeosporioides could provide basis for controlling strategy against the pathogen. The histone acetyl-transferase encoding gene CgGCN5 was identified in the genome of C. gloeosporioides. In the present study, the CgGCN5 knock-out mutant and the complementation mutant strains were constructed by homologous recombination strategy. Phenotype analysis revealed that the vegetative growth and sporulation were significantly reduced in the knock-out mutant. The pathogenicity of the mutant to rubber leaves was also significantly impaired. Further analysis suggested that the knock-out of CgGCN5 lead to the loss of penetration ability of the pathogen to cellophane. In addition, the impair of growth and virulence were restored in the complementation strain. The results suggested that CgGCN5 plays important roles in the regulation of growth and pathogenicity of C. gloeosporioides.