title: Phosphodiesterase MoPdeH targets MoMck1 of the conserved mitogen-activated protein (MAP) kinase signalling pathway to regulate cell wall integrity in rice blast fungus Magnaporthe oryzae.
abstract: In the rice blast fungus Magnaporthe oryzae, the high-affinity cyclic adenosine monophosphate (cAMP) phosphodiesterase MoPdeH is important not only for cAMP signalling and pathogenicity, but also for cell wall integrity (CWI) maintenance through an unknown mechanism. By utilizing affinity purification, we found that MoPdeH interacts with MoMck1, one of the components of the mitogen-activated protein (MAP) kinase cascade that regulates CWI. Overexpression of MoMCK1 suppressed defects in autolysis and pathogenicity of the ΔMopdeH mutant, although partially, suggesting that MoPdeH plays a critical role in CWI maintenance mediated by the MAP kinase pathway. We found that MoMck1 and two other MAP kinase cascade components, MoMkk1 and MoMps1, modulate intracellular cAMP levels by regulating the expression of MoPDEH through a feedback loop. In addition, disruption of MoMKK1 resulted in less aerial hyphal formation, defective asexual development and attenuated pathogenicity. Moreover, MoMkk1 plays a role in the response to osmotic stress via regulation of MoOsm1 phosphorylation levels, whereas endoplasmic reticulum (ER) stress enhances MoMps1 phosphorylation and loss of the MAP kinase cascade component affects the unfolded protein response (UPR) pathway. Taken together, our findings demonstrate that MoPdeH functions upstream of the MoMck1-MoMkk1-MoMps1 MAP kinase pathway to regulate CWI, and that MoPdeH also mediates crosstalk between the cAMP signalling pathway, the osmotic sensing high osmolarity glycerol (HOG) pathway and the dithiothreitol (DTT)-induced UPR pathway in M. oryzae.
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Ziyi
authors.initials: Z
authors.lastname: Yin
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Tang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Jingzhen
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Xinyu
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Lina
authors.initials: L
authors.lastname: Yang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Chuyun
authors.initials: C
authors.lastname: Gao
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Xiaobo
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, LA, 70118, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Wang
authors.affiliation: Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, 210095, China.|Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, 210095, China.
authors.forename: Zhengguang
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D002473:Cell Wall / Q000378:metabolism*; D017124:Conserved Sequence; D000242:Cyclic AMP / Q000378:metabolism; D059865:Endoplasmic Reticulum Stress; D004789:Enzyme Activation; D005656:Fungal Proteins / Q000378:metabolism*; D025301:Hyphae / Q000254:growth & development; D042541:Intracellular Space / Q000378:metabolism; D020935:MAP Kinase Signaling System; D020082:Magnaporthe / Q000201:enzymology* / Q000254:growth & development / Q000472:pathogenicity; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009154:Mutation / Q000235:genetics; D012275:Oryza / Q000382:microbiology*; D009995:Osmosis; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D010766:Phosphorylation; D010935:Plant Diseases / Q000382:microbiology*; D011485:Protein Binding; D012100:Reproduction, Asexual; D013312:Stress, Physiological; D056811:Unfolded Protein Response
chemical_list: D005656:Fungal Proteins; D000242:Cyclic AMP; D020928:Mitogen-Activated Protein Kinases; D010727:Phosphoric Diester Hydrolases
keywords: MAP kinase signalling pathway; Magnaporthe oryzae; cell wall integrity; cyclic adenosine monophosphate (cAMP); infection-related morphogenesis; phosphodiesterase