title: Regulation of Nod1 by Hsp90 chaperone complex.
abstract: Nod1 and Nod2 proteins play important roles in mammalian innate immune responses as intracellular sensors for bacterial peptidoglycan. Nod1 and Nod2 share structural homology with many R proteins involved in plant disease resistance. It has been demonstrated that plant Hsp90 and its co-chaperone RAR1 are implicated in R-mediated disease resistance. Here the Chp-1 gene encoding a mammalian homologue of plant RAR1 was identified as a new target for transcriptional activation by heat shock factor 1 (HSF1), a stress-responsive HSF isoform. In addition, Nod1 is demonstrated to be a client protein of the Hsp90 chaperone complex containing the Chp-1. Chp-1 interacts with the tetratricopeptide repeat (TPR) domain of protein phosphatase 5 (PP5) and the ATPase domain of Hsp90 via two distinct zinc-binding cysteine and histidine rich domains (CHORDs). These findings suggest a common regulatory mechanism involving the Hsp90 chaperone complex in R-mediated disease resistance in plants and Nod1-mediated innate immune response in mammals.
authors.affiliation: School of Chemical and Biological Engineering, Seoul National University, Seoul 151-744, Republic of Korea.
authors.forename: Ji-Sook
authors.initials: JS
authors.lastname: Hahn
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002478:Cells, Cultured; D004268:DNA-Binding Proteins / Q000235:genetics / Q000502:physiology*; D005347:Fibroblasts / Q000378:metabolism; D018841:HSP90 Heat-Shock Proteins / Q000378:metabolism*; D000076249:Heat Shock Transcription Factors; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D018832:Molecular Chaperones; D053474:Nod1 Signaling Adaptor Protein; D009687:Nuclear Proteins / Q000378:metabolism; D010749:Phosphoprotein Phosphatases / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000502:physiology*; D020798:Two-Hybrid System Techniques
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D002352:Carrier Proteins; C478383:Chp-1 protein, mouse; D004268:DNA-Binding Proteins; D018841:HSP90 Heat-Shock Proteins; D000076249:Heat Shock Transcription Factors; C490017:Hsf1 protein, mouse; D018832:Molecular Chaperones; C119067:NOD1 protein, human; D053474:Nod1 Signaling Adaptor Protein; D009687:Nuclear Proteins; D014157:Transcription Factors; D010749:Phosphoprotein Phosphatases; C089641:protein phosphatase 5