Intrinsic sterol- and phosphatidylcholine transfer activities of 17 beta-hydroxysteroid dehydrogenase type IV

J Steroid Biochem Mol Biol. 1995 Dec;55(5-6):549-53. doi: 10.1016/0960-0760(95)00205-7.

Abstract

Previous studies have shown that the 80 kDa 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) type IV comprises distinct domains, including an N-terminal region related to the short chain alcohol dehydrogenase multigene family and a C-terminal part related to the lipid transfer protein sterol carrier protein 2 (SCP2). In this study, we have investigated whether the SCP2-related part of the 80 kDa protein leads to an intrinsic sterol and phospholipid transfer activity, as shown earlier for the 60 kDa SCP2-related peroxisomal 3-ketoacyl CoA thiolase with intrinsic sterol and phospholipid transfer activity called sterol carrier protein x (SCPx). Our results indicate that a fraction rich in the 80 kDa form of 17 beta-HSD type IV exhibits high transfer activities for 7-dehydrocholesterol and phosphatidylcholine. In addition, a purified recombinant peptide derived from the SCP2-related domain of the 17 beta-HSD type IV has about 30% of the transfer activities for 7-dehydrocholesterol and phosphatidylcholine seen with purified recombinant human SCP2. We conclude that the 80 kDa type IV 17 beta-HSD represents a potentially multifunctional protein with intrinsic in vitro sterol and phospholipid transfer activity in addition to its enzymatic activity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 17-Hydroxysteroid Dehydrogenases / metabolism*
  • Amino Acid Sequence
  • Animals
  • Carrier Proteins / metabolism
  • Humans
  • Isoenzymes / metabolism
  • Mice
  • Molecular Sequence Data
  • Phosphatidylcholines / metabolism*
  • Phylogeny
  • Plant Proteins*
  • Rats
  • Recombinant Proteins
  • Sequence Alignment
  • Sequence Homology, Amino Acid
  • Sterols / metabolism*
  • Substrate Specificity
  • Swine

Substances

  • Carrier Proteins
  • Isoenzymes
  • Phosphatidylcholines
  • Plant Proteins
  • Recombinant Proteins
  • Sterols
  • sterol carrier proteins
  • 17-Hydroxysteroid Dehydrogenases