Identification and characterization of a selective radioligand for ELOVL6

J Biochem. 2009 Sep;146(3):429-37. doi: 10.1093/jb/mvp088. Epub 2009 Jun 8.

Abstract

ELOVL6, a member of the elongation of very long-chain fatty acids (ELOVL) family, has recently been identified as the rate-limiting enzyme for the elongation of palmitoyl-CoA. ELOVL6 deficient mice are protected from high-fat diet induced insulin resistance, suggesting that ELOVL6 might be a promising target for the treatment of metabolic disorders. Despite the increasing interest in Elovl6 as a therapeutic target, the lack of chemical tools for this enzyme has limited further elucidation of the biochemical and pharmacological properties of ELOVL6. We have identified Compound-A, a potent inhibitor for ELOVL6, by screening our company library and subsequently optimizing hit compounds. Compound-A potently inhibited human and mouse ELOVL6 and displayed >100-fold greater selectivity for ELOVL6 over other ELOVL family members. Consistent with its potent and selective inhibitory activity toward ELOVL6, [(3)H]Compound-A bound to ELOVL6 with high affinity while showing no specific binding to other ELOVL enzymes. The observation that [(3)H]Compound-A bound to ELOVL6 in a palmitoyl-CoA-dependent manner in the absence of malonyl-CoA and NADPH suggests that Compound-A might recognize an enzyme-substrate complex, e.g. an acyl-enzyme intermediate. Collectively, these observations demonstrate that Compound-A and its tritiated form are useful tools for biochemical and pharmacological characterization of ELOVL6.

MeSH terms

  • Acetyltransferases / antagonists & inhibitors*
  • Acetyltransferases / genetics
  • Acetyltransferases / metabolism
  • Acyl Coenzyme A / metabolism
  • Animals
  • Cell Line
  • Drug Evaluation, Preclinical
  • Enzyme Inhibitors / chemical synthesis
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / metabolism*
  • Fatty Acid Elongases
  • Fatty Acids / analysis
  • Gene Expression
  • Hepatocytes / chemistry
  • Hepatocytes / enzymology
  • Humans
  • Indoles / chemical synthesis
  • Indoles / chemistry
  • Indoles / metabolism*
  • Inhibitory Concentration 50
  • Isoenzymes
  • Kinetics
  • Ligands
  • Mice
  • Microsomes / enzymology
  • Molecular Structure
  • Oxadiazoles / chemical synthesis
  • Oxadiazoles / chemistry
  • Oxadiazoles / metabolism*
  • Palmitic Acid / metabolism
  • Pichia / genetics
  • Pichia / metabolism
  • Polymerase Chain Reaction
  • Protein Binding
  • Radioligand Assay
  • Recombinant Fusion Proteins / antagonists & inhibitors
  • Recombinant Fusion Proteins / metabolism
  • Regression Analysis
  • Spectrometry, Mass, Electrospray Ionization

Substances

  • 3-(3-cyclohexyl-1-(2-(dimethylamino)-2-oxoethyl)-6-(4-methyl-5-oxo-4,5-dihydro-1,2,4-oxadiazol-3-yl)-1H-indol-2-yl)-N,N-dimethylbenzamide
  • Acyl Coenzyme A
  • ELOVL6 protein, human
  • Elovl6 protein, mouse
  • Enzyme Inhibitors
  • Fatty Acids
  • Indoles
  • Isoenzymes
  • Ligands
  • Oxadiazoles
  • Recombinant Fusion Proteins
  • Palmitic Acid
  • Acetyltransferases
  • Fatty Acid Elongases