Paper
ABA-Activated SnRK2 Protein Kinase is Required for Dehydration Stress Signaling in Arabidopsis

Authors: Yoshida R.¹; Hobo T.¹; Ichimura K.¹; Mizoguchi T.¹; Takahashi F.¹; Aronso J.²; Ecker J.R.²; Shinozaki K.¹

Source: Plant and Cell Physiology, Volume 43, Number 12, 15 December 2002 , pp. 1473-1483(11)

Buy & download fulltext article:

Price: $42.29 plus tax (Refund Policy)

Abstract:

Protein phosphorylation has pivotal roles in ABA and osmotic stress signaling in higher plants. Two protein phosphatase genes, ABI1 and ABI2, are known to regulate these signaling pathways in Arabidopsis. The identity of ABA-activated protein kinases required for the ABA signaling, however, remains to be elucidated. Here we demonstrate that two protein kinases, p44 and p42, were activated by ABA in Arabidopsis T87 cultured cells, and at least one protein kinase, p44, was activated not only by ABA but also by low humidity in Arabidopsis plants. Analysis of T-DNA knockout mutants and biochemical analysis using a specific antibody revealed that the p44 is encoded by a SnRK2-type protein kinase gene, SRK2E. The srk2e mutation resulted in a wilty phenotype mainly due to loss of stomatal closure in response to a rapid humidity decrease. ABA-inducible gene expression of rd22 and rd29B was suppressed in srk2e. These results show that SRK2E plays an important role in ABA signaling in response to water stress.

Document Type: Regular paper

Affiliations: 1: Laboratory of Plant Molecular Biology, RIKEN Tsukuba Institute, 3-1-1, Koyadai, Tsukuba, Ibaraki, 305-0074 Japan 2: The Salk Institute for Biological Studies, 2262 Vista La Nisa, Carlsbad, CA 92009-8711, U.S.A.

Publication date: 2002-12-15

More about this publication?

Plant and Cell Physiology is an international journal devoted to the publication of original papers pertaining to physiology, biochemistry, biophysics, chemistry, genetics, molecular biology, gene engineering and cell engineering of plants and microorganisms.