Endothelial cell palmitoylproteomic identifies novel lipid-modified targets and potential substrates for protein acyl transferases

Circ Res. 2012 May 11;110(10):1336-44. doi: 10.1161/CIRCRESAHA.112.269514. Epub 2012 Apr 10.


Rationale: Protein S-palmitoylation is the posttranslational attachment of a saturated 16-carbon palmitic acid to a cysteine side chain via a thioester bond. Palmitoylation can affect protein localization, trafficking, stability, and function. The extent and roles of palmitoylation in endothelial cell (EC) biology is not well-understood, partly because of technological limits on palmitoylprotein detection.

Objective: To develop a method using acyl-biotinyl exchange technology coupled with mass spectrometry to globally isolate and identify palmitoylproteins in ECs.

Methods and results: More than 150 putative palmitoyl proteins were identified in ECs using acyl-biotinyl exchange and mass spectrometry. Among the novel palmitoylproteins identified is superoxide dismutase-1, an intensively studied enzyme that protects all cells from oxidative damage. Mutation of cysteine-6 prevents palmitoylation, leads to reduction in superoxide dismutase-1 activity in vivo and in vitro, and inhibits nuclear localization, thereby supporting a functional role for superoxide dismutase-1 palmitoylation. Moreover, we used acyl-biotinyl exchange to search for substrates of particular protein acyl transferases in ECs. We found that palmitoylation of the cell adhesion protein platelet endothelial cell adhesion molecule-1 is dependent on the protein acyl transferase ZDHHC21. We show that knockdown of ZDHHC21 leads to reduced levels of platelet endothelial cell adhesion molecule-1 at the cell surface.

Conclusions: Our data demonstrate the utility of EC palmitoylproteomics to reveal new insights into the role of this important posttranslational lipid modification in EC biology.

Publication types

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

MeSH terms

  • Acetyltransferases / genetics
  • Acetyltransferases / metabolism*
  • Acyltransferases / genetics
  • Acyltransferases / metabolism*
  • Amino Acid Sequence
  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Endothelial Cells / cytology
  • Endothelial Cells / enzymology*
  • HEK293 Cells
  • Human Umbilical Vein Endothelial Cells
  • Humans
  • Lipoylation / physiology*
  • Molecular Sequence Data
  • Platelet Endothelial Cell Adhesion Molecule-1 / metabolism*
  • Proteomics / methods
  • RNA, Small Interfering / genetics
  • Substrate Specificity
  • Superoxide Dismutase / genetics
  • Superoxide Dismutase / metabolism
  • Superoxide Dismutase-1


  • Platelet Endothelial Cell Adhesion Molecule-1
  • RNA, Small Interfering
  • SOD1 protein, human
  • Superoxide Dismutase
  • Superoxide Dismutase-1
  • Acyltransferases
  • ZDHHC21 protein, human
  • Acetyltransferases
  • protein acyltransferase