title: Alternaric acid stimulates  phosphorylation of His-tagged RiCDPK2, a calcium-dependent protein kinase in  potato plants.
abstract: Calcium-dependent protein kinases (CDPK) are an essential component of plant defense mechanisms against pathogens. We investigated the effect of alternaric acid, a host-specific toxin produced by the plant fungal pathogen Alternaria solani (Pleosporaceae), on a putative plasma membrane and cytosolic kinase RiCDPK2 of potato (Solanum tuberosum) and on hypersensitive cell death of host potato cells. Alternaric acid, in the presence of Ca²⁺ and Mg²⁺, stimulated in vitro phosphorylation of His-tagged RiCDPK2, a Ca²⁺-dependent protein kinase found in potato plants. We concluded that Ca²⁺ and Mg²⁺ play an important role in the interaction between alternaric acid and RiCDPK2. Based on our observations, alternaric acid regulates RiCDPK2 kinase during the infection process in an interaction between host and A. solani, leading to the inhibition of hypersensitive cell death in the host. We suggest that alternaric acid is a primary determinant by which A. solani stimulates CDPK activity in the host, suppressing hypersensitive cell death.
authors.affiliation: Biotechnology Program, Department of Environmental Sciences, COMSATS Institute of Information Technology, Abbottabad, Pakistan.
authors.forename: A
authors.initials: A
authors.lastname: Hassan
authors.forename: T
authors.initials: T
authors.lastname: Okuta
authors.forename: M
authors.initials: M
authors.lastname: Kato
authors.forename: N
authors.initials: N
authors.lastname: Hatsugai
authors.forename: Y
authors.initials: Y
authors.lastname: Sano
authors.forename: T
authors.initials: T
authors.lastname: Ishimori
authors.forename: K
authors.initials: K
authors.lastname: Okazaki
authors.forename: M A
authors.initials: MA
authors.lastname: Doullah
authors.forename: M M
authors.initials: MM
authors.lastname: Shah
mesh_terms: D000143:Acids / Q000494:pharmacology*; D000528:Alternaria / Q000737:chemistry; D001681:Biological Assay; D002118:Calcium / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D005231:Fatty Acids, Unsaturated / Q000494:pharmacology*; D006639:Histidine / Q000378:metabolism*; D018551:Solanum lycopersicum / Q000187:drug effects / Q000382:microbiology; D008274:Magnesium / Q000494:pharmacology; D009842:Oligopeptides / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D010935:Plant Diseases / Q000382:microbiology; D018515:Plant Leaves / Q000187:drug effects / Q000382:microbiology; D011494:Protein Kinases / Q000378:metabolism*; D011753:Pyrones / Q000494:pharmacology*; D011993:Recombinant Fusion Proteins / Q000378:metabolism*; D011198:Solanum tuberosum / Q000187:drug effects* / Q000201:enzymology* / Q000382:microbiology; D017871:Calcium-Calmodulin-Dependent Protein Kinases
chemical_list: D000143:Acids; D002118:Calcium; D005231:Fatty Acids, Unsaturated; D006639:Histidine; D008274:Magnesium; D009842:Oligopeptides; D011494:Protein Kinases; D011753:Pyrones; D011993:Recombinant Fusion Proteins; D017871:Calcium-Calmodulin-Dependent Protein Kinases; C471213:His-His-His-His-His-His