Active and dynamic mitochondrial S-depalmitoylation revealed by targeted fluorescent probes

Nat Commun. 2018 Jan 23;9(1):334. doi: 10.1038/s41467-017-02655-1.


The reversible modification of cysteine residues by thioester formation with palmitate (S-palmitoylation) is an abundant lipid post-translational modification (PTM) in mammalian systems. S-palmitoylation has been observed on mitochondrial proteins, providing an intriguing potential connection between metabolic lipids and mitochondrial regulation. However, it is unknown whether and/or how mitochondrial S-palmitoylation is regulated. Here we report the development of mitoDPPs, targeted fluorescent probes that measure the activity levels of "erasers" of S-palmitoylation, acyl-protein thioesterases (APTs), within mitochondria of live cells. Using mitoDPPs, we discover active S-depalmitoylation in mitochondria, in part mediated by APT1, an S-depalmitoylase previously thought to reside in the cytosol and on the Golgi apparatus. We also find that perturbation of long-chain acyl-CoA cytoplasm and mitochondrial regulatory proteins, respectively, results in selective responses from cytosolic and mitochondrial S-depalmitoylases. Altogether, this work reveals that mitochondrial S-palmitoylation is actively regulated by "eraser" enzymes that respond to alterations in mitochondrial lipid homeostasis.

Publication types

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

MeSH terms

  • A549 Cells
  • Acyl Coenzyme A / metabolism
  • Fluorescent Dyes / metabolism*
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Kinetics
  • Lipoylation
  • MCF-7 Cells
  • Microscopy, Confocal
  • Mitochondria / metabolism*
  • Mitochondrial Dynamics*
  • RNA Interference
  • Thiolester Hydrolases / genetics
  • Thiolester Hydrolases / metabolism*


  • Acyl Coenzyme A
  • Fluorescent Dyes
  • LYPLA1 protein, human
  • Thiolester Hydrolases