The Arabidopsis thaliana TIR-NB-LRR R-protein, RPP1A; protein localization and constitutive activation of defence by truncated alleles in tobacco and Arabidopsis.

Abstract

Specific recognition of Hyaloperonospora parasitica isolate Cala2 by Arabidopsis thaliana Ws-0 is mediated by the resistance gene RPP1A. Transient expression of different truncations of RPP1A in tobacco leaves revealed that its TIR-NB-ARC portion is sufficient to induce an elicitor-independent cell death. In stable transgenic lines of Arabidopsis, overexpression of the RPP1A TIR-NB-ARC domains (E12) using the 35S promoter leads to broad-spectrum resistance to virulent strains of H. parasitica and Pseudomonas syringae DC3000. The TIR-NB-ARC-mediated constitutive immunity is due to activation of the salicylic acid-dependent resistance pathway and is relieved by either a mutation in EDS1 or the presence of the salicylate hydroxylase gene, NahG. Growth of 35S::E12 plants is reduced, a phenotype observed in many constitutively resistant mutants. RPP1A carries a hydrophobic peptide at its N-terminus that directs the RPP1A protein into membranes, though it may not be the sole determinant mediating membrane association of RPP1A. Two-phase partitioning and sucrose density gradient sedimentation established that RPP1A resides in the endoplasmic reticulum and/or Golgi apparatus.

• Authors: L Michael Weaver, Michal R Swiderski, Yan Li, Jonathan D G Jones
• Journal: The Plant journal : for cell and molecular biology (Plant J) Vol. 47 Issue 6 Pg. 829-40 (Sep 2006) ISSN: 0960-7412 [Print] England
• PMID: 16889647 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Arabidopsis Proteins

Topics

• Alleles
• Arabidopsis (genetics, physiology)
• Arabidopsis Proteins (metabolism)
• Plants, Genetically Modified
• Promoter Regions, Genetic
• Reverse Transcriptase Polymerase Chain Reaction
• Tobacco (genetics, physiology)