title: A novel higher plant protein tyrosine phosphatase interacts with SNF1-related protein kinases via a KIS (kinase interaction sequence) domain.
abstract: A novel protein phosphatase in Arabidopsis thaliana was identified by database searching. This protein, designated AtPTPKIS1, contains a protein tyrosine phosphatase (PTP) catalytic domain and a kinase interaction sequence (KIS) domain. It is predicted to interact with plant SNF1-related kinases (SnRKs), representing central regulators of metabolic and stress responses. AtPTPKIS1 has close homologues in other plant species, both dicots and monocots, but is not found in other kingdoms. The tomato homologue of AtPTPKIS1 was expressed as a recombinant protein and shown to hydrolyse a generic phosphatase substrate, and phosphotyrosine residues in synthetic peptides. The KIS domain of AtPTPKIS1 was shown to interact with the plant SnRK AKIN11 both in vivo in the yeast two-hybrid system, and in vitro in a GST-fusion 'pull down' assay. The genomes of Arabidopsis and other plants contain further predicted proteins related to AtPTPKIS1, which could also interact with SnRKs and act in novel regulatory and signalling pathways.
authors.affiliation: CLRC, Daresbury Laboratory, Warrington, Cheshire, UK. a.p.fordham-skelton@dl.ac.uk
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Fordham-Skelton
authors.forename: Paul
authors.initials: P
authors.lastname: Chilley
authors.forename: Victoria
authors.initials: V
authors.lastname: Lumbreras
authors.forename: Sabrina
authors.initials: S
authors.lastname: Reignoux
authors.forename: Tim R
authors.initials: TR
authors.lastname: Fenton
authors.forename: Christina C
authors.initials: CC
authors.lastname: Dahm
authors.forename: Montserrat
authors.initials: M
authors.lastname: Pages
authors.forename: John A
authors.initials: JA
authors.lastname: Gatehouse
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D017124:Conserved Sequence / Q000235:genetics; D020224:Expressed Sequence Tags; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D047908:Intracellular Signaling Peptides and Proteins; D018551:Solanum lycopersicum / Q000201:enzymology / Q000235:genetics; D008969:Molecular Sequence Data; D011485:Protein Binding; D017346:Protein Serine-Threonine Kinases / Q000235:genetics / Q000378:metabolism*; D017027:Protein Tyrosine Phosphatases / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction / Q000235:genetics; D020798:Two-Hybrid System Techniques; D015003:Yeasts / Q000235:genetics; D054637:Dual-Specificity Phosphatases
chemical_list: D029681:Arabidopsis Proteins; D047908:Intracellular Signaling Peptides and Proteins; D017346:Protein Serine-Threonine Kinases; D017027:Protein Tyrosine Phosphatases; C490996:At5g01820 protein, Arabidopsis; C553186:At3g52180 protein, Arabidopsis; D054637:Dual-Specificity Phosphatases