Abstract Glycoside hydrolase family 76 (GH76) proteins with their endo-α-1,6-mannanases domains are required for cell wall biogenesis in several model fungi, including Saccharomyces cerevisiae, Candida albicans, and Neurospora crassa. However, biological roles of GH76 proteins in phytopathogenic fungi remain unknown. The genome of the rice blast fungus Pyricularia oryzae contains seven GH76 protein-encoding genes. In this study, we functionally characterized one of them, PoGH76-1, which is highly expressed in conidia. The deletion of PoGH76-1 led to severe defects in colony growth and conidiation. Conidia produced by the PoGH76-1 knockout mutant were mostly one- and two-celled. Deletion of PoGH76-1 also resulted in impaired appressorium maturation, appressorial penetration, and attenuated virulence on rice leaves. Taken together, our findings suggest that PoGH76-1 functions as an important determinant of fungal growth, development, and virulence in P. oryzae.

中文翻译：

---

糖苷水解酶家族 76 的一个成员参与稻瘟病菌的生长、分生孢子和毒力

摘要 糖苷水解酶家族 76 (GH76) 蛋白及其内切-α-1,6-甘露聚糖酶结构域是多种模型真菌（包括酿酒酵母、白色念珠菌和粗糙脉孢菌）的细胞壁生物发生所必需的。然而，GH76 蛋白在植物致病真菌中的生物学作用仍然未知。稻瘟病真菌 Pyricularia oryzae 的基因组包含七个 GH76 蛋白编码基因。在这项研究中，我们对其中之一 PoGH76-1 进行了功能表征，PoGH76-1 在分生孢子中高度表达。PoGH76-1 的缺失导致菌落生长和分生孢子形成的严重缺陷。PoGH76-1 敲除突变体产生的分生孢子主要是单细胞和双细胞。PoGH76-1 的缺失还导致附着胞成熟受损、附着胞渗透受损，并减弱水稻叶片的毒力。综合起来，