Membrane topology and search for potential redox partners of colon cancer-specific cytochrome P450 2W1

FEBS Lett. 2016 Feb;590(3):330-9. doi: 10.1002/1873-3468.12063. Epub 2016 Feb 2.

Abstract

Cytochrome P450 2W1 (CYP2W1) is a colon tumor-specific enzyme, suggested as a potential target for cancer therapy. In contrast to other endoplasmic reticulum P450s, we found completely inverted ER membrane topology of CYP2W1 using different approaches (redox sensitive luciferase assay and protease protection assay) and demonstrated that canonical CYP reductants, cytochrome P450 reductase, and cytochrome b5 cannot serve as electron donors for CYP2W1. Moreover, the reduced catalytic activity of the Asn177 mutant that is modified by glycan moieties in the wild-type enzyme indicates a functional relevance of CYP2W1 glycosylation.

Keywords: P450 reductase; cytochrome P450 2W1; cytochrome b5; electron donor; glycosylation; membrane topology.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Substitution
  • Asparagine / metabolism
  • Colonic Neoplasms / enzymology*
  • Colonic Neoplasms / metabolism
  • Colonic Neoplasms / pathology
  • Cytochrome P-450 Enzyme System / chemistry
  • Cytochrome P-450 Enzyme System / genetics
  • Cytochrome P-450 Enzyme System / metabolism*
  • Cytochrome P450 Family 2
  • Electron Transport
  • Endoplasmic Reticulum / chemistry
  • Endoplasmic Reticulum / enzymology*
  • Endoplasmic Reticulum / metabolism
  • Endoplasmic Reticulum / pathology
  • Glycosylation
  • Green Fluorescent Proteins / chemistry
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / metabolism
  • HEK293 Cells
  • Humans
  • Luciferases / chemistry
  • Luciferases / genetics
  • Luciferases / metabolism
  • Mutant Proteins / chemistry
  • Mutant Proteins / metabolism
  • Neoplasm Proteins / antagonists & inhibitors
  • Neoplasm Proteins / chemistry
  • Neoplasm Proteins / genetics
  • Neoplasm Proteins / metabolism*
  • Oxidation-Reduction
  • Protein Interaction Domains and Motifs
  • Protein Processing, Post-Translational
  • Proteolysis
  • RNA Interference
  • Recombinant Fusion Proteins / metabolism
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / metabolism

Substances

  • Mutant Proteins
  • Neoplasm Proteins
  • Recombinant Fusion Proteins
  • Recombinant Proteins
  • Green Fluorescent Proteins
  • Asparagine
  • Cytochrome P-450 Enzyme System
  • Luciferases
  • CYP2W1 protein, human
  • Cytochrome P450 Family 2