Metabolomics Analysis Identifies Sphingolipids as Key Signaling Moieties in Appressorium Morphogenesis and Function in Magnaporthe oryzae

mBio

Li-Juan Mao¹  Caroline Mota Fernandes²  Maurizio Del Poeta²  Lin Li³  Fu-Cheng Lin³  Xiao-Hong Liu³  Shuang Liang³  Yong Zhang³  Yun-Yun Wei³  Xue-Ming Zhu³  Naweed I. Naqvi⁴  Ping-Ping Liu⁵  Qing-Xia Zheng⁵  Hui-Na Zhou⁵ 

[1] Analysis Center of Agrobiology and Environmental Science, Zhejiang University, Hangzhou, China;Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA;State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou, China;Temasek Life Sciences Laboratory and Department of Biological Sciences, National University of Singapore, Singapore;Zhengzhou Tobacco Research Institute of CNTC, Zhengzhou, China;

关键词: appressorium development;    early sphingolipid signaling;    inducer;    metabolomics analysis;    pathogenicity;    rice blast fungus;   

DOI  :  10.1128/mBio.01467-19

来源: DOAJ

【 摘 要 】

ABSTRACT The blast fungus initiates infection using a heavily melanized, dome-shaped infection structure known as the appressorium, which forcibly ruptures the cuticle to enter the rice leaf tissue. How this process takes place remains not fully understood. Here, we used untargeted metabolomics analyses to profile the metabolome of developing appressoria and identified significant changes in six key metabolic pathways, including early sphingolipid biosynthesis. Analyses employing small molecule inhibitors, gene disruption, or genetic and chemical complementation demonstrated that ceramide compounds of the sphingolipid biosynthesis pathway are essential for normal appressorial development controlled by mitosis. In addition, ceramide was found to act upstream from the protein kinase C-mediated cell wall integrity pathway during appressorium repolarization and pathogenicity in rice blast. Further discovery of the sphingolipid biosynthesis pathway revealed that glucosylceramide (GlcCer) synthesized by ceramide is the key substance affecting the pathogenicity of Magnaporthe oryzae. Our results provide new insights into the chemical moieties involved in the infection-related signaling networks, thereby revealing a potential target for the development of novel control agents against the major disease of rice and other cereals. IMPORTANCE Our untargeted analysis of metabolomics throughout the course of pathogenic development gave us an unprecedented high-resolution view of major shifts in metabolism that occur in the topmost fungal pathogen that infects rice, wheat, barley, and millet. Guided by these metabolic insights, we demonstrated their practical application by using two different small-molecule inhibitors of sphingolipid biosynthesis enzymes to successfully block the pathogenicity of M. oryzae. Our study thus defines the sphingolipid biosynthesis pathway as a key step and potential target that can be exploited for the development of antifungal agents. Furthermore, future investigations that exploit such important metabolic intermediates will further deepen our basic understanding of the molecular mechanisms underlying the establishment of fungal blast disease in important cereal crops.

【 授权许可】

Unknown