Raft localisation of FcgammaRIIa and efficient signaling are dependent on palmitoylation of cysteine 208

Immunol Lett. 2006 Apr 15;104(1-2):118-23. doi: 10.1016/j.imlet.2005.11.007. Epub 2005 Dec 5.

Abstract

Ligand-dependent aggregation of FcgammaRIIa initiates multiple biochemical processes including the translocation to detergent resistant membrane domains (DRMs) and receptor tyrosine phosphorylation. Palmitoylation of cysteine residues is considered to be one process that assists in the localisation of proteins to DRMs. Within the juxtamembrane region of FcgammaRIIa there is cysteine residue (C208) that we show to be palmitoylated. Mutation of this cysteine residue results in the disruption of FcgammaRIIa translocation to DRMs as empirically defined by insolubility at high Triton X-100 concentrations. This study also demonstrates that the lack of lipid raft association diminishes FcgammaRIIa signaling as measured by receptor phosphorylation and calcium mobilisation functions suggesting that FcgammaRIIa signaling is partially dependent on lipid rafts.

MeSH terms

  • Animals
  • Antigens, CD / analysis
  • Antigens, CD / genetics
  • Antigens, CD / metabolism*
  • B-Lymphocytes / immunology*
  • Calcium Signaling
  • Cell Line, Tumor
  • Cysteine / genetics
  • Cysteine / metabolism*
  • Humans
  • Membrane Microdomains / chemistry
  • Membrane Microdomains / drug effects
  • Membrane Microdomains / metabolism*
  • Mice
  • Mutation
  • Octoxynol / pharmacology
  • Palmitates / metabolism
  • Phosphorylation
  • Protein Processing, Post-Translational* / drug effects
  • Receptors, IgG / analysis
  • Receptors, IgG / genetics
  • Receptors, IgG / metabolism*
  • Tyrosine / metabolism

Substances

  • Antigens, CD
  • Fc gamma receptor IIA
  • Palmitates
  • Receptors, IgG
  • Tyrosine
  • Octoxynol
  • Cysteine