The innate immune sensor NLRC3 attenuates Toll-like receptor signaling via modification of the signaling adaptor TRAF6 and transcription factor NF-κB.

Published

Journal Article

Several members of the NLR family of sensors activate innate immunity. In contrast, we found here that NLRC3 inhibited Toll-like receptor (TLR)-dependent activation of the transcription factor NF-κB by interacting with the TLR signaling adaptor TRAF6 to attenuate Lys63 (K63)-linked ubiquitination of TRAF6 and activation of NF-κB. We used bioinformatics to predict interactions between NLR and TRAF proteins, including interactions of TRAF with NLRC3. In vivo, macrophage expression of Nlrc3 mRNA was diminished by the administration of lipopolysaccharide (LPS) but was restored when cellular activation subsided. To assess biologic relevance, we generated Nlrc3(-/-) mice. LPS-treated Nlrc3(-/-) macrophages had more K63-ubiquitinated TRAF6, nuclear NF-κB and proinflammatory cytokines. Finally, LPS-treated Nlrc3(-/-) mice had more signs of inflammation. Thus, signaling via NLRC3 and TLR constitutes a negative feedback loop. Furthermore, prevalent NLR-TRAF interactions suggest the formation of a 'TRAFasome' complex.

Full Text

Duke Authors

Cited Authors

  • Schneider, M; Zimmermann, AG; Roberts, RA; Zhang, L; Swanson, KV; Wen, H; Davis, BK; Allen, IC; Holl, EK; Ye, Z; Rahman, AH; Conti, BJ; Eitas, TK; Koller, BH; Ting, JP-Y

Published Date

  • September 2012

Published In

Volume / Issue

  • 13 / 9

Start / End Page

  • 823 - 831

PubMed ID

  • 22863753

Pubmed Central ID

  • 22863753

Electronic International Standard Serial Number (EISSN)

  • 1529-2916

Digital Object Identifier (DOI)

  • 10.1038/ni.2378

Language

  • eng

Conference Location

  • United States