Sadat Md Abu, Jeon Junhyun, Mir Albely Afifa, Choi Jaeyoung, Choi Jaehyuk, Lee Yong-Hwan
Department of Agricultural Biotechnology, Plant Genomics and Breeding Institute, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Korea.
Center for Fungal Pathogenesis, Plant Genomics and Breeding Institute, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Korea.
PLoS One. 2014 Jun 24;9(6):e100726. doi: 10.1371/journal.pone.0100726. eCollection 2014.
Considering implication of diacylglycerol in both metabolism and signaling pathways, maintaining proper levels of diacylglycerol (DAG) is critical to cellular homeostasis and development. Except the PIP2-PLC mediated pathway, metabolic pathways leading to generation of DAG converge on dephosphorylation of phosphatidic acid catalyzed by lipid phosphate phosphatases. Here we report the role of such enzymes in a model plant pathogenic fungus, Magnaporthe oryzae. We identified five genes encoding putative lipid phosphate phosphatases (MoLPP1 to MoLPP5). Targeted disruption of four genes (except MoLPP4) showed that MoLPP3 and MoLPP5 are required for normal progression of infection-specific development and proliferation within host plants, whereas MoLPP1 and MoLPP2 are indispensable for fungal pathogenicity. Reintroduction of MoLPP3 and MoLPP5 into individual deletion mutants restored all the defects. Furthermore, exogenous addition of saturated DAG not only restored defect in appressorium formation but also complemented reduced virulence in both mutants. Taken together, our data indicate differential roles of lipid phosphate phosphatase genes and requirement of proper regulation of cellular DAGs for fungal development and pathogenesis.
鉴于二酰基甘油在代谢和信号通路中的作用，维持适当水平的二酰基甘油（DAG）对于细胞稳态和发育至关重要。除了磷脂酰肌醇-4,5-二磷酸（PIP2）-磷脂酶C（PLC）介导的途径外，导致DAG生成的代谢途径都汇聚于脂质磷酸磷酸酶催化的磷脂酸去磷酸化过程。在此，我们报道了这类酶在模式植物病原真菌稻瘟病菌中的作用。我们鉴定出五个编码假定脂质磷酸磷酸酶的基因（MoLPP1至MoLPP5）。对四个基因（MoLPP4除外）进行靶向破坏后发现，MoLPP3和MoLPP5是宿主植物内感染特异性发育和增殖正常进行所必需的，而MoLPP1和MoLPP2对于真菌致病性是不可或缺的。将MoLPP3和MoLPP5重新导入各自的缺失突变体中可恢复所有缺陷。此外，外源添加饱和DAG不仅恢复了附着胞形成的缺陷，还弥补了两个突变体中降低的毒力。综上所述，我们的数据表明脂质磷酸磷酸酶基因具有不同作用，以及细胞DAG的适当调控对真菌发育和致病性的必要性。
