title: A protein phosphatase 2C involved in ABA signal transduction in Arabidopsis thaliana.
abstract: The plant hormone abscisic acid (ABA) mediates various responses such as stomatal closure, the maintenance of seed dormancy, and the inhibition of plant growth. All three responses are affected in the ABA-insensitive mutant abi1 of Arabidopsis thaliana, suggesting that an early step in the signaling of ABA is controlled by the ABI1 locus. The ABI1 gene was cloned by chromosome walking, and a missense mutation was identified in the structural gene of the abi1 mutant. The ABI1 gene encodes a protein with high similarity to protein serine or threonine phosphatases of type 2C with the novel feature of a putative Ca2+ binding site. Thus, the control of the phosphorylation state of cell signaling components by the ABI1 product could mediate pleiotropic hormone responses.
authors.affiliation: Institute of Plant Sciences, Swiss Federal Institute of Technology, Zürich.
authors.forename: K
authors.initials: K
authors.lastname: Meyer
authors.forename: M P
authors.initials: MP
authors.lastname: Leube
authors.forename: E
authors.initials: E
authors.lastname: Grill
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000378:metabolism*; D029681:Arabidopsis Proteins; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D016386:Chromosome Walking; D003001:Cloning, Molecular; D017343:Genes, Plant; D005819:Genetic Markers; D008969:Molecular Sequence Data; D009154:Mutation; D010749:Phosphoprotein Phosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D030821:Plants, Genetically Modified; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D005819:Genetic Markers; D000040:Abscisic Acid; C087434:ABI1 protein, Arabidopsis; D010749:Phosphoprotein Phosphatases; D002118:Calcium