Small-molecule inhibition of APT1 affects Ras localization and signaling

Nat Chem Biol. 2010 Jun;6(6):449-56. doi: 10.1038/nchembio.362. Epub 2010 Apr 25.

Abstract

Cycles of depalmitoylation and repalmitoylation critically control the steady-state localization and function of various peripheral membrane proteins, such as Ras proto-oncogene products. Interference with acylation using small molecules is a strategy to modulate cellular localization--and thereby unregulated signaling--caused by palmitoylated Ras proteins. We present the knowledge-based development and characterization of a potent inhibitor of acyl protein thioesterase 1 (APT1), a bona fide depalmitoylating enzyme that is, so far, poorly characterized in cells. The inhibitor, palmostatin B, perturbs the cellular acylation cycle at the level of depalmitoylation and thereby causes a loss of the precise steady-state localization of palmitoylated Ras. As a consequence, palmostatin B induces partial phenotypic reversion in oncogenic HRasG12V-transformed fibroblasts. We identify APT1 as one of the thioesterases in the acylation cycle and show that this protein is a cellular target of the inhibitor.

Publication types

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

MeSH terms

  • Animals
  • Cell Line
  • Dogs
  • Down-Regulation
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology*
  • Humans
  • Kidney / drug effects
  • Kidney / physiology
  • Ligands
  • Lipase / chemistry
  • Lipase / metabolism
  • Lipoylation / drug effects
  • Models, Molecular
  • Propiolactone / analogs & derivatives*
  • Propiolactone / chemical synthesis
  • Propiolactone / chemistry
  • Propiolactone / pharmacology
  • Protein Conformation
  • Signal Transduction
  • Stomach / enzymology
  • Thiolester Hydrolases / antagonists & inhibitors*
  • Thiolester Hydrolases / chemistry*
  • Thiolester Hydrolases / genetics
  • ras Proteins / drug effects
  • ras Proteins / metabolism
  • ras Proteins / physiology*

Substances

  • Enzyme Inhibitors
  • Ligands
  • palmostatin B
  • Propiolactone
  • Lipase
  • LYPLA1 protein, human
  • Thiolester Hydrolases
  • ras Proteins