AtCPK1 calcium-dependent protein kinase mediates pathogen resistance in Arabidopsis.

Abstract

In mammals, lipid bodies play a key role during pathological and infectious diseases. However, our knowledge on the function of plant lipid bodies, apart from their role as the major site of lipid storage in seed tissues, remains limited. Here, we provide evidence that a calcium-dependent protein kinase (CPK) mediates pathogen resistance in Arabidopsis. AtCPK1 expression is rapidly induced by fungal elicitors. Loss-of-function mutants of AtCPK1 exhibit higher susceptibility to pathogen infection compared to wild-type plants. Conversely, over-expression of AtCPK1 leads to accumulation of salicylic acid (SA) and constitutive expression of SA-regulated defence and disease resistance genes, which, in turn, results in broad-spectrum protection against pathogen infection. Expression studies in mutants affected in SA-mediated defence responses revealed an interlocked feedback loop governing AtCPK1 expression and components of the SA-dependent signalling pathway. Moreover, we demonstrate the dual localization of AtCPK1 in lipid bodies and peroxisomes. Overall, our findings identify AtCPK1 as a component of the innate immune system of Arabidopsis plants.

• Authors: María Coca, Blanca San Segundo
• Journal: The Plant journal : for cell and molecular biology (Plant J) Vol. 63 Issue 3 Pg. 526-40 (Aug 2010) ISSN: 1365-313X [Electronic] England
• PMID: 20497373 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2010 The Authors. Journal compilation © 2010 Blackwell Publishing Ltd.

Chemical References

• ATCDPK1 protein, Arabidopsis
• Arabidopsis Proteins
• Calcium-Binding Proteins
• Protein Kinases
• Salicylic Acid

Topics

• Arabidopsis (enzymology, genetics, microbiology)
• Arabidopsis Proteins (genetics, metabolism)
• Calcium-Binding Proteins (genetics, metabolism)
• Fungi (isolation & purification, pathogenicity, physiology)
• Gene Expression Profiling
• Genes, Plant
• Protein Kinases (genetics, metabolism)
• Salicylic Acid (metabolism)
• Signal Transduction
• Transcriptome