title: A hypermorphic mutation in the protein phosphatase 2C HAB1 strongly affects ABA signaling in Arabidopsis.
abstract: Protein phosphatases of the 2C family (PP2C) function in the regulation of several signaling pathways from prokaryotes to eukaryotes. In Arabidopsis thaliana, the HAB1 PP2C is a negative regulator of the stress hormone abscisic acid (ABA) signaling. Here, we show that plants expressing a mutant form of HAB1 in which Gly246 was mutated to Asp (G246D) display strong ABA insensitive phenotypes. Our results indicate that the G246D mutation has a hypermorphic rather than a dominant negative effect. The data suggest that this mutation localized in a conserved motif in the PP2C catalytic domain could be used in other PP2Cs to reveal their biological functions.
authors.affiliation: Division of Biological Sciences, Cell and Developmental Biology Section, Center for Molecular Genetics, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0116, USA. narobus@yahoo.com
authors.forename: Nadia
authors.initials: N
authors.lastname: Robert
authors.forename: Sylvain
authors.initials: S
authors.lastname: Merlot
authors.forename: Vinh
authors.initials: V
authors.lastname: N'guyen
authors.forename: Aurélien
authors.initials: A
authors.lastname: Boisson-Dernier
authors.forename: Julian I
authors.initials: JI
authors.lastname: Schroeder
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D008969:Molecular Sequence Data; D010749:Phosphoprotein Phosphatases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D017354:Point Mutation; D000071636:Protein Phosphatase 2C; D017386:Sequence Homology, Amino Acid; D015398:Signal Transduction
chemical_list: D000040:Abscisic Acid; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C