Evidence for a multi-domain structure for hormone-sensitive lipase

FEBS Lett. 1996 Oct 28;396(1):90-4. doi: 10.1016/0014-5793(96)01076-9.

Abstract

Hormone-sensitive lipase (HSL) is a multi-functional enzyme involved in several aspects of lipid metabolism. Limited tryptic digestion of HSL led to selective loss of activity against lipid substrates but not against the water-soluble substrate, p-nitrophenyl butyrate. Following labelling of the active site of HSL with either [3H]di-isopropylfluorophosphate or [14C]orlistat, tryptic digestion of HSL generated a stable radiolabelled domain of molecular mass approx. 17.6 kDa, consistent with this representing a catalytic domain of HSL capable of hydrolysing water-soluble but not lipid substrates. Following phosphorylation of HSL by cyclic AMP-dependent protein kinase, limited tryptic digestion produced a stable phosphorylated domain of molecular mass 11.5 kDa. Based on these experimental data a model for a domain structure of HSL is proposed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Binding Sites
  • Butyrates / chemistry
  • Butyrates / metabolism
  • Electrophoresis, Polyacrylamide Gel / methods
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Lactones / chemistry
  • Lactones / metabolism
  • Molecular Sequence Data
  • Orlistat
  • Peptide Fragments / chemistry
  • Peptide Fragments / metabolism
  • Phosphorylation
  • Protein Conformation
  • Sterol Esterase / antagonists & inhibitors
  • Sterol Esterase / chemistry*
  • Sterol Esterase / metabolism*
  • Substrate Specificity
  • Trypsin / chemistry
  • Trypsin / metabolism

Substances

  • Butyrates
  • Enzyme Inhibitors
  • Lactones
  • Peptide Fragments
  • 4-nitrophenyl butyrate
  • Orlistat
  • Sterol Esterase
  • Trypsin