A hypermorphic mutation in the protein phosphatase 2C HAB1 strongly affects ABA signaling in Arabidopsis.
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.
Robert
Nadia
N
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
Merlot
Sylvain
S
N'guyen
Vinh
V
Boisson-Dernier
Aurélien
A
Schroeder
Julian I
JI
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
D000040:Abscisic Acid; D010749:Phosphoprotein Phosphatases; D000071636:Protein Phosphatase 2C