A hypermorphic mutation in the protein phosphatase 2C HAB1 strongly affects ABA signaling in Arabidopsis

FEBS Lett. 2006 Aug 21;580(19):4691-6. doi: 10.1016/j.febslet.2006.07.047. Epub 2006 Jul 24.

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.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Abscisic Acid / metabolism*
  • Amino Acid Sequence
  • Arabidopsis / enzymology
  • Arabidopsis / genetics*
  • Base Sequence
  • Molecular Sequence Data
  • Phosphoprotein Phosphatases / chemistry
  • Phosphoprotein Phosphatases / genetics
  • Phosphoprotein Phosphatases / metabolism*
  • Point Mutation*
  • Protein Phosphatase 2C
  • Sequence Homology, Amino Acid
  • Signal Transduction*

Substances

  • Abscisic Acid
  • Phosphoprotein Phosphatases
  • Protein Phosphatase 2C