Expression of Peripherin 2 (PRPH2) in retinal pigment epithelial cells

Abstract

Purpose : Peripherin 2 (PRPH2) protein, encoded by the PRPH2 gene, also known as Retinal Degeneration Slow (RDS), is a transmembrane protein found in the outer segment of both rod and cones photoreceptor cells. Complete loss of PRPH2 prevents photoreceptor outer segment formation. Up to date there have been identified more than 200 mutations in the PRPH2 gene causing a heterogenous set of retinal diseases characterized by various phenotypes. Some of those phenotypes result in generalized degeneration while others affect predominantly a more focal area. That prompt us to examine if PRPH2 is expressed in retinal pigment epithelial (RPE) cells.

Methods : Here we use human fetal primary (hfpRPE), ARPE-19 and human induced pluripotent stem cell (iPSC)-derived RPE cells to examine the expression of PRPH2 at RNA level. We use agarose gel and Sanger DNA sequencing to verify our results. In addition, we examine the protein levels of PRPH2 by Western Blot in hfpRPE and ARPE-19 cells. Finally, we used human retinal tissue isolated from retinal disease-free donors to examine the PRPH2 protein level by WB.

Results : We found that PRPH2 is expressed in low quantities in RNA level of hfpRPE, ARPE-19 and iPSC-derived RPE cells. PRPH2 wasn’t detectable by WB in hfpRPE and ARPE-19 cells. PRPH2 was detected by WB in Retina and RPE in human donor samples. PRPH2 protein levels were higher in macular versus periphery RPE isolated from human donor eyes.

Conclusions : PRPH2 is expressed in low amounts in retinal pigment epithelial cells. There is higher expression of PRPH2 in macular compared to periphery retinal pigment epithelial cells.

This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.