Resistance proteins: molecular switches of plant defence

Curr Opin Plant Biol. 2006 Aug;9(4):383-90. doi: 10.1016/j.pbi.2006.05.009. Epub 2006 May 19.


Specificity of the plant innate immune system is often conferred by resistance (R) proteins. Most R proteins contain leucine-rich repeats (LRRs), a central nucleotide-binding site (NBS) and a variable amino-terminal domain. The LRRs are mainly involved in recognition, whereas the amino-terminal domain determines signalling specificity. The NBS forms part of a nucleotide binding (NB)-ARC domain that presumably functions as a molecular switch. The conserved nature of NB-ARC proteins makes it possible to map mutations of R protein residues onto the crystal structures of related NB-ARC proteins, providing hypotheses for the functional roles of these residues. A functional model emerges in which the LRRs control the molecular state of the NB-ARC domain. Pathogen recognition triggers nucleotide-dependent conformational changes that might induce oligomerisation, thereby providing a scaffold for activation of downstream signalling components.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Molecular Biology
  • Plant Diseases / microbiology*
  • Plant Proteins / chemistry*
  • Plant Proteins / metabolism*
  • Protein Conformation


  • Plant Proteins