title: Interaction of calmodulin, a sorting nexin and kinase-associated protein phosphatase with the Brassica oleracea S locus receptor kinase.
abstract: Recognition of self-pollen during the self-incompatibility response in Brassica oleracea is mediated by the binding of a secreted peptide (the S locus cysteine-rich protein) to the S locus receptor kinase (SRK), a member of the plant receptor kinase (PRK) superfamily. Here, we describe the characterization of three proteins that interact with the cytosolic kinase domain of SRK. A B. oleracea homolog of Arabidopsis kinase-associated protein phosphatase was shown to interact with and dephosphorylate SRK and was itself phosphorylated by SRK. Yeast (Saccharomyces cerevisiae) two-hybrid screens identified two additional interactors, calmodulin and a sorting nexin, both of which have been implicated in receptor kinase down-regulation in animals. A calmodulin-binding site was identified in sub-domain VIa of the SRK kinase domain. The binding site is conserved and functional in several other members of the PRK family. The sorting nexin also interacted with diverse members of the PRK family, suggesting that all three of the interacting proteins described here may play a general role in signal transduction by this family of proteins.
authors.affiliation: Reproduction et Développement des Plantes, Unité Mixte de Recherche 5667, Institut National de la Recherche Agronomique, Université Claude Bernard Lyon, Ecole Normale Supérieure de Lyon, 46 Allée d'Italie, 69364 Lyon cedex 07, France.
authors.forename: Vincent
authors.initials: V
authors.lastname: Vanoosthuyse
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Tichtinsky
authors.forename: Christian
authors.initials: C
authors.lastname: Dumas
authors.forename: Thierry
authors.initials: T
authors.lastname: Gaude
authors.forename: J Mark
authors.initials: JM
authors.lastname: Cock
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001937:Brassica / Q000145:classification / Q000201:enzymology*; D002147:Calmodulin / Q000378:metabolism*; D002352:Carrier Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000378:metabolism*; D010766:Phosphorylation; D010802:Phylogeny; D010940:Plant Proteins / Q000378:metabolism; D011494:Protein Kinases / Q000737:chemistry / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D033921:Vesicular Transport Proteins
chemical_list: D002147:Calmodulin; D002352:Carrier Proteins; D010940:Plant Proteins; D033921:Vesicular Transport Proteins; D011494:Protein Kinases; C079832:S-receptor kinase; D010749:Phosphoprotein Phosphatases