A Novel Binding Protein of Single Immunoglobulin IL-1 Receptor-Related Molecule: Paralemmin-3

Biochem Biophys Res Commun. 2011 Jan 28;404(4):1029-33. doi: 10.1016/j.bbrc.2010.12.104. Epub 2010 Dec 25.


Previous studies have shown that single immunoglobulin IL-1 receptor-related molecule (SIGIRR) is a negative regulator of Toll-Interleukin-1 receptor signaling. Nevertheless, the molecular mechanism of the negatively regulatory effect of SIGIRR remains unknown. Using a yeast two-hybrid screen, we identified paralemmin-3 (PALM3) as a novel binding protein of SIGIRR. This interaction of SIGIRR with PALM3 was confirmed by coimmunoprecipitation in mammalian cells. In addition, the PALM3 mRNA expression was upregulated by lipopolysaccharide (LPS)-stimulation in a human alveolar epithelial cell line (A549 cells). Furthermore, silencing PALM3 by RNA interference inhibited the release of inflammatory cytokines in A549 cells after LPS-stimulation. These results suggest that PALM3 may function as an adaptor in the LPS- Toll-like receptor 4 signaling and the interaction of SIGIRR with PALM3 may partly account for the mechanism of the negatively regulatory effect of SIGIRR.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins / genetics
  • Carrier Proteins / metabolism*
  • Cell Line
  • Cytokines / metabolism
  • Humans
  • Immunoprecipitation
  • Lipopolysaccharides / metabolism
  • Phosphoproteins / genetics
  • Phosphoproteins / metabolism*
  • Protein Binding
  • RNA Interference
  • Receptors, Interleukin-1 / genetics
  • Receptors, Interleukin-1 / metabolism*
  • Signal Transduction
  • Toll-Like Receptor 4 / metabolism
  • Two-Hybrid System Techniques


  • Adaptor Proteins, Signal Transducing
  • Carrier Proteins
  • Cytokines
  • Lipopolysaccharides
  • Phosphoproteins
  • Receptors, Interleukin-1
  • SIGIRR protein, human
  • Toll-Like Receptor 4
  • paralemmin-3 protein, human