论文信息:Ming Xu, Xiaoning Gao, Jiliang Chen, Zhiyuan Yin, Hao Feng, Lili Huang. The feruloyl esterase genes are required for full pathogenicity of the apple tree canker pathogen Valsa mali . Molecular Plant Pathology (2018) 19(6), 1353–1363
JCR分区Q1,IF=4.697
论文摘要:Apple Valsa canker, caused by the fungus Valsa mali , is one of the most destructive diseases of apple trees in East Asia. Feruloyl esterases (ferulic acid esterases, FAEs), which belong to a sub- class of carboxylic esterases, can cleave ester bonds that cross- link hydroxycinnamic acids and arabinoxylans or certain pectins in plant cell walls. However, a pathogenic role of FAE has not been demonstrated in plant-pathogenic fungi. In this study, the FAE gene family, including one type A, one type B, three type C and two type D FAE genes, was identified in V. mali. Five of the seven FAE genes had highly elevated transcript levels in V. mali– apple tree bark interactions compared with mycelia grown in axenic culture. Signal peptides of the VmFAEs were confirmed using yeast signal sequence trap assays. To examine whether FAEs are required for the pathogenicity of V. mali, seven single- and six double-gene deletion mutants were generated. Com- pared with the wild-type, three of the seven FAE single-deletion mutants showed significantly reduced pathogenicity and three of the six FAE double-deletion mutants exhibited greater reductions in pathogenicity, suggesting the joint action of FAEs in the V. mali–apple tree interaction. Most of the FAE mutants that exhib- ited a significant reduction in pathogenicity had significantly lower FAE activity than the wild-type fungus. These results indi- cate that secreted FAEs are required for the full pathogenicity of the phytopathogenic fungus V. mali .