title: Elicitor-mediated oligomerization of the tobacco N disease resistance protein.
abstract: Plant nucleotide binding site-leucine-rich repeat (NBS-LRR) proteins are similar to the nucleotide binding oligomerization domain (NOD) protein family in their domain structure. It has been suggested that most NOD proteins rely on ligand-mediated oligomerization for function, and we have tested this possibility with the N protein of tobacco (Nicotiana tabacum). The N gene for resistance to Tobacco mosaic virus (TMV) is a member of the Toll-interleukin receptor (TIR)-NBS-LRR class of plant disease resistance (R) genes that recognizes the helicase domain from the TMV replicase. Using transient expression followed by immunoprecipitation, we show that the N protein oligomerizes in the presence of the elicitor. The oligomerization was not affected by silencing Nicotiana benthamiana ENHANCED DISEASE SUSCEPTIBILITY1 and N REQUIREMENT GENE1 cofactors of N-mediated resistance, but it was abolished by a mutation in the P-loop motif. However, loss-of-function mutations in the RNBS-A motif and in the TIR domain retain the ability to oligomerize. From these results, we conclude that oligomerization is an early event in the N-mediated resistance to TMV.
authors.affiliation: Sainsbury Laboratory, John Ines Centre, Norwich NR4 7UH, United Kingdom.
authors.forename: Pere
authors.initials: P
authors.lastname: Mestre
authors.forename: David C
authors.initials: DC
authors.lastname: Baulcombe
mesh_terms: D020816:Amino Acid Motifs; D017124:Conserved Sequence; D015870:Gene Expression; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism; D007113:Immunity, Innate; D008954:Models, Biological; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D010446:Peptide Fragments / Q000378:metabolism; D018515:Plant Leaves / Q000821:virology; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism*; D011485:Protein Binding; D020836:Protein Structure, Quaternary; D016415:Sequence Alignment; D014026:Nicotiana / Q000033:anatomy & histology / Q000378:metabolism* / Q000821:virology; D014027:Tobacco Mosaic Virus / Q000502:physiology; D051193:Toll-Like Receptors / Q000737:chemistry / Q000378:metabolism
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; C089425:N protein, Nicotiana glutinosa; D010446:Peptide Fragments; D010940:Plant Proteins; D051193:Toll-Like Receptors; C475510:tyrosyl-prolyl-tyrosyl-aspartyl-valyl-prolyl-aspartyl-tyrosyl-alanine