Functional analysis and molecular dynamics simulation of LOX-1 K167N polymorphism reveal alteration of receptor activity

PLoS One. 2009;4(2):e4648. doi: 10.1371/journal.pone.0004648. Epub 2009 Feb 27.

Abstract

The human lectin-like oxidized low density lipoprotein receptor 1 LOX-1, encoded by the ORL1 gene, is the major scavenger receptor for oxidized low density lipoprotein in endothelial cells. Here we report on the functional effects of a coding SNP, c.501G>C, which produces a single amino acid change (K>N at codon 167). Our study was aimed at elucidating whether the c.501G>C polymorphism changes the binding affinity of LOX-1 receptor altering its function. The presence of p.K167N mutation reduces ox-LDL binding and uptake. Ox-LDL activated extracellular signal-regulated kinases 1 and 2 (ERK 1/2) is inhibited. Furthermore, ox-LDL induced biosynthesis of LOX-1 receptors is dependent on the p.K167N variation. In human macrophages, derived from c.501G>C heterozygous individuals, the ox-LDL induced LOX-1 46 kDa band is markedly lower than in induced macrophages derived from c.501G>C controls. Investigation of p.K167N mutation through molecular dynamics simulation and electrostatic analysis suggests that the ox-LDL binding may be attributed to the coupling between the electrostatic potential distribution and the asymmetric flexibility of the basic spine residues. The N/N-LOX-1 mutant has either interrupted electrostatic potential and asymmetric fluctuations of the basic spine arginines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • COS Cells
  • Chlorocebus aethiops
  • Codon
  • Heterozygote
  • Humans
  • Macrophages / metabolism
  • Mitogen-Activated Protein Kinase 1 / metabolism
  • Mitogen-Activated Protein Kinase 3 / metabolism
  • Mutation
  • Polymorphism, Single Nucleotide*
  • Scavenger Receptors, Class E / genetics*
  • Scavenger Receptors, Class E / metabolism
  • Static Electricity

Substances

  • Codon
  • OLR1 protein, human
  • Scavenger Receptors, Class E
  • Mitogen-Activated Protein Kinase 1
  • Mitogen-Activated Protein Kinase 3