Cutting edge: Mouse NAIP1 detects the type III secretion system needle protein.

Journal Article (Journal Article)

The NAIP/NLRC4 inflammasomes activate caspase-1 in response to bacterial type III secretion systems (T3SSs). Inadvertent injection of the T3SS rod protein and flagellin into the cytosol is detected through murine NAIP2 and NAIP5/6, respectively. In this study, we identify the agonist for the orphan murine NAIP1 receptor as the T3SS needle protein. NAIP1 is poorly expressed in resting mouse bone marrow-derived macrophages; however, priming with polyinosinic-polycytidylic acid induces it and confers needle protein sensitivity. Further, overexpression of NAIP1 in immortalized bone marrow-derived macrophages by retroviral transduction enabled needle detection. In contrast, peritoneal cavity macrophages basally express NAIP1 and respond to needle protein robustly, independent of priming. Human macrophages are known to express only one NAIP gene, which detects the needle protein, but not rod or flagellin. Thus, murine NAIP1 is functionally analogous to human NAIP.

Full Text

Duke Authors

Cited Authors

  • Rayamajhi, M; Zak, DE; Chavarria-Smith, J; Vance, RE; Miao, EA

Published Date

  • October 15, 2013

Published In

Volume / Issue

  • 191 / 8

Start / End Page

  • 3986 - 3989

PubMed ID

  • 24043898

Pubmed Central ID

  • PMC3819181

Electronic International Standard Serial Number (EISSN)

  • 1550-6606

Digital Object Identifier (DOI)

  • 10.4049/jimmunol.1301549


  • eng

Conference Location

  • United States