title: The Arabidopsis CDPK-SnRK superfamily of protein kinases.
abstract: The CDPK-SnRK superfamily consists of seven types of serine-threonine protein kinases: calcium-dependent protein kinase (CDPKs), CDPK-related kinases (CRKs), phosphoenolpyruvate carboxylase kinases (PPCKs), PEP carboxylase kinase-related kinases (PEPRKs), calmodulin-dependent protein kinases (CaMKs), calcium and calmodulin-dependent protein kinases (CCaMKs), and SnRKs. Within this superfamily, individual isoforms and subfamilies contain distinct regulatory domains, subcellular targeting information, and substrate specificities. Our analysis of the Arabidopsis genome identified 34 CDPKs, eight CRKs, two PPCKs, two PEPRKs, and 38 SnRKs. No definitive examples were found for a CCaMK similar to those previously identified in lily (Lilium longiflorum) and tobacco (Nicotiana tabacum) or for a CaMK similar to those in animals or yeast. CDPKs are present in plants and a specific subgroup of protists, but CRKs, PPCKs, PEPRKs, and two of the SnRK subgroups have been found only in plants. CDPKs and at least one SnRK have been implicated in decoding calcium signals in Arabidopsis. Analysis of intron placements supports the hypothesis that CDPKs, CRKs, PPCKs and PEPRKs have a common evolutionary origin; however there are no conserved intron positions between these kinases and the SnRK subgroup. CDPKs and SnRKs are found on all five Arabidopsis chromosomes. The presence of closely related kinases in regions of the genome known to have arisen by genome duplication indicates that these kinases probably arose by divergence from common ancestors. The PlantsP database provides a resource of continuously updated information on protein kinases from Arabidopsis and other plants.
authors.affiliation: Department of Plant Biology and Program in Genetics, University of New Hampshire, 46 College Road, Durham 03824, USA. emhrabak@cisunix.unh.edu
authors.forename: Estelle M
authors.initials: EM
authors.lastname: Hrabak
authors.forename: Catherine W M
authors.initials: CW
authors.lastname: Chan
authors.forename: Michael
authors.initials: M
authors.lastname: Gribskov
authors.forename: Jeffrey F
authors.initials: JF
authors.lastname: Harper
authors.forename: Jung H
authors.initials: JH
authors.lastname: Choi
authors.forename: Nigel
authors.initials: N
authors.lastname: Halford
authors.forename: Jorg
authors.initials: J
authors.lastname: Kudla
authors.forename: Sheng
authors.initials: S
authors.lastname: Luan
authors.forename: Hugh G
authors.initials: HG
authors.lastname: Nimmo
authors.forename: Michael R
authors.initials: MR
authors.lastname: Sussman
authors.forename: Martine
authors.initials: M
authors.lastname: Thomas
authors.forename: Kay
authors.initials: K
authors.lastname: Walker-Simmons
authors.forename: Jian-Kang
authors.initials: JK
authors.lastname: Zhu
authors.forename: Alice C
authors.initials: AC
authors.lastname: Harmon
mesh_terms: D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins; D030541:Databases, Genetic; D005810:Multigene Family; D010802:Phylogeny; D010940:Plant Proteins; D011494:Protein Kinases / Q000235:genetics*; D017346:Protein Serine-Threonine Kinases / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D029681:Arabidopsis Proteins; D010940:Plant Proteins; D011494:Protein Kinases; D017346:Protein Serine-Threonine Kinases; C490996:At5g01820 protein, Arabidopsis