Li Mengying, Liu Xinyu, Liu Zhixi, Sun Yi, Liu Muxing, Wang Xiaoli, Zhang Haifeng, Zheng Xiaobo, Zhang Zhengguang
Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, China.
Agricultural Bureau of Ningxiang County, Changsha 410600, China.
PLoS One. 2016 Sep 8;11(9):e0162243. doi: 10.1371/journal.pone.0162243. eCollection 2016.
N-linked glycosylation is a way of glycosylation for newly synthesized protein, which plays a key role in the maturation and transport of proteins. Glycoside hydrolases (GHs) are essential in this process, and are involved in processing of N-linked glycoproteins or degradation of carbohydrate structures. Here, we identified and characterized MoGls2 in Magnaporthe oryzae, which is a yeast glucosidase II homolog Gls2 and is required for trimming the final glucose in N-linked glycans and normal cell wall synthesis. Target deletion of MoGLS2 in M. oryzae resulted in a reduced mycelial growth, an increased conidial production, delayed conidial germination and loss the ability of sexual reproduction. Pathogenicity assays revealed that the ΔMogls2 mutant showed significantly decreased in virulence and infectious growth. Further studies showed that the mutant was less sensitive to salt and osmotic stress, and increased sensitivity to cell wall stresses. Additionally, the ΔMogls2 mutant showed a defect in cell wall integrity. Our results indicate that MoGls2 is a key protein for the growth and development of M. oryzae, involving in the regulation of asexual/sexual development, stress response, cell wall integrity and infectious growth.
N-连接糖基化是新合成蛋白质的一种糖基化方式，在蛋白质的成熟和运输过程中起关键作用。糖苷水解酶（GHs）在这一过程中至关重要，参与N-连接糖蛋白的加工或碳水化合物结构的降解。在此，我们鉴定并表征了稻瘟病菌中的MoGls2，它是酵母葡糖苷酶II同源物Gls2，是修剪N-连接聚糖中最终葡萄糖和正常细胞壁合成所必需的。在稻瘟病菌中对MoGLS2进行靶向缺失导致菌丝生长减少、分生孢子产量增加、分生孢子萌发延迟以及丧失有性生殖能力。致病性测定表明，ΔMogls2突变体的毒力和侵染性生长显著降低。进一步研究表明，该突变体对盐和渗透胁迫的敏感性较低，而对细胞壁胁迫的敏感性增加。此外，ΔMogls2突变体在细胞壁完整性方面存在缺陷。我们的结果表明，MoGls2是稻瘟病菌生长和发育的关键蛋白，参与无性/有性发育、应激反应、细胞壁完整性和侵染性生长的调控。
