Correlation of structure and function in the human hotdog-fold enzyme hTHEM4

Biochemistry. 2012 Aug 21;51(33):6490-2. doi: 10.1021/bi300968n. Epub 2012 Aug 9.

Abstract

Human THEM4 (hTHEM4) is comprised of a catalytically active hotdog-fold acyl-CoA thioesterase domain and an N-terminal domain of unknown fold and function. hTHEM4 has been linked to Akt1 regulation and cell apoptosis. Herein, we report the X-ray structure of hHTEM4 bound with undecan-2-one-CoA. Structure guided mutagenesis was carried out to confirm the catalytic residues. The N-terminal domain is shown to be partially comprised of irregular and flexible secondary structure, reminiscent of a protein-binding domain. We demonstrate direct hTHEM4-Akt1 binding by immunoprecipitation and by inhibition of Akt1 kinase activity, thus providing independent evidence that hTHEM4 is an Akt1 negative regulator.

Publication types

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

MeSH terms

  • Acyl Coenzyme A / chemistry
  • Acyl Coenzyme A / metabolism
  • Adaptor Proteins, Signal Transducing / chemistry*
  • Adaptor Proteins, Signal Transducing / metabolism
  • Catalytic Domain / drug effects
  • Crystallography, X-Ray
  • Humans
  • Membrane Proteins / chemistry*
  • Membrane Proteins / metabolism
  • Models, Molecular
  • Protein Structure, Secondary
  • Proto-Oncogene Proteins c-akt / chemistry
  • Proto-Oncogene Proteins c-akt / metabolism
  • Thiolester Hydrolases / antagonists & inhibitors
  • Thiolester Hydrolases / chemistry*
  • Thiolester Hydrolases / metabolism

Substances

  • Acyl Coenzyme A
  • Adaptor Proteins, Signal Transducing
  • Membrane Proteins
  • Proto-Oncogene Proteins c-akt
  • THEM4 protein, human
  • Thiolester Hydrolases

Associated data

  • PDB/4GAH