A new rhodopsin R135W mutation induces endoplasmic reticulum stress and apoptosis in retinal pigment epithelial cells

J Cell Physiol. 2019 Aug;234(8):14100-14108. doi: 10.1002/jcp.28100. Epub 2019 Jan 12.

Abstract

Rhodopsin mutations are associated with the autosomal-dominant form of retinitis pigmentosa (RP). Here we report simultaneous occurrence of RP associated with bilateral nanophthalmos and acute angle-closure glaucoma in patient with a new mutation in rhodopsin (R135W). ARPE-19 cells were transfected with myc-tagged wild-type (WT) and R135W rhodopsin constructs. The half-life of WT and R135W rhodopsin was analyzed via cycloheximide chase analysis. We found that R135W rhodopsin was accumulated in the endoplasmic reticulum (ER) and induced unfolded protein response (UPR) and apoptosis. Moreover, chaperone HSP70 alleviated ER stress and prevented apoptosis induced by R135W rhodopsin by attenuating UPR signaling. These findings reveal the novel pathogenic mechanism of RP and suggest that chaperone HSP70 has potential therapeutic significance for RP.

Keywords: HSP70; apoptosis; endoplasmic reticulum; mutation; retinitis pigmentosa; rhodopsin; unfolded protein response.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Apoptosis / genetics
  • Cell Line
  • Child
  • Child, Preschool
  • Endoplasmic Reticulum / genetics
  • Endoplasmic Reticulum Stress / genetics
  • Epithelial Cells / metabolism
  • Epithelial Cells / pathology
  • Exome Sequencing
  • Female
  • Glaucoma, Angle-Closure / complications
  • Glaucoma, Angle-Closure / genetics*
  • Glaucoma, Angle-Closure / pathology
  • HSP72 Heat-Shock Proteins / genetics
  • Humans
  • Hyperopia / complications
  • Hyperopia / genetics*
  • Hyperopia / pathology
  • Male
  • Microphthalmos / complications
  • Microphthalmos / genetics*
  • Microphthalmos / pathology
  • Middle Aged
  • Molecular Chaperones / genetics
  • Mutation / genetics
  • Pedigree
  • Retinal Pigment Epithelium / metabolism
  • Retinal Pigment Epithelium / pathology
  • Retinitis Pigmentosa / complications
  • Retinitis Pigmentosa / genetics*
  • Retinitis Pigmentosa / pathology
  • Rhodopsin / genetics*
  • Signal Transduction / genetics
  • Unfolded Protein Response

Substances

  • HSP72 Heat-Shock Proteins
  • Molecular Chaperones
  • Rhodopsin

Supplementary concepts

  • Nanophthalmos 1