Bifunctional fatty acid chemical reporter for analyzing S-palmitoylated membrane protein-protein interactions in mammalian cells

J Am Chem Soc. 2015 Jan 21;137(2):556-9. doi: 10.1021/ja502109n. Epub 2015 Jan 12.


Studying the functions of S-palmitoylated proteins in cells can be challenging due to the membrane targeting property and dynamic nature of protein S-palmitoylation. New strategies are therefore needed to specifically capture S-palmitoylated protein complexes in cellular membranes for dissecting their functions in vivo. Here we present a bifunctional fatty acid chemical reporter, x-alk-16, which contains an alkyne and a diazirine, for metabolic labeling of S-palmitoylated proteins and photo-cross-linking of their involved protein complexes in mammalian cells. We demonstrate that x-alk-16 can be metabolically incorporated into known S-palmitoylated proteins such as H-Ras and IFITM3, a potent antiviral protein, and induce covalent cross-linking of IFITM3 oligomerization as well as its specific interactions with other membrane proteins upon in-cell photoactivation. Moreover, integration of x-alk-16-induced photo-cross-linking with label-free quantitative proteomics allows identification of new IFITM3 interacting proteins.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alkynes / chemistry
  • Cell Membrane / metabolism
  • Diazomethane / chemistry
  • Fatty Acids / chemistry*
  • Fatty Acids / metabolism*
  • HEK293 Cells
  • Humans
  • Lipoylation*
  • Membrane Proteins / metabolism*
  • Molecular Probes / chemistry*
  • Molecular Probes / metabolism*
  • Protein Binding


  • Alkynes
  • Fatty Acids
  • Membrane Proteins
  • Molecular Probes
  • Diazomethane