Skip to Main content Skip to Navigation
Journal articles

Expression of Rod-Derived Cone Viability Factor: Dual Role of CRX in Regulating Promoter Activity and Cell-Type Specificity.

Abstract : BACKGROUND: RdCVF and RdCVF2, encoded by the nucleoredoxin-like genes NXNL1 and NXNL2, are trophic factors with therapeutic potential that are involved in cone photoreceptor survival. Studying how their expression is regulated in the retina has implications for understanding both their activity and the mechanisms determining cell-type specificity within the retina. METHODOLOGY/PRINCIPAL FINDINGS: In order to define and characterize their promoters, a series of luciferase/GFP reporter constructs that contain various fragments of the 5'-upstream region of each gene, both murine and human, were tested in photoreceptor-like and non-photoreceptor cell lines and also in a biologically more relevant mouse retinal explant system. For NXNL1, 5'-deletion analysis identified the human -205/+57 bp and murine -351/+51 bp regions as having promoter activity. Moreover, in the retinal explants these constructs drove expression specifically to photoreceptor cells. For NXNL2, the human -393/+27 bp and murine -195/+70 bp regions were found to be sufficient for promoter activity. However, despite the fact that endogenous NXNL2 expression is photoreceptor-specific within the retina, neither of these DNA sequences nor larger upstream regions demonstrated photoreceptor-specific expression. Further analysis showed that a 79 bp NXNL2 positive regulatory sequence (-393 to 315 bp) combined with a 134 bp inactive minimal NXNL1 promoter fragment (-77 to +57 bp) was able to drive photoreceptor-specific expression, suggesting that the minimal NXNL1 fragment contains latent elements that encode cell-type specificity. Finally, based on bioinformatic analysis that suggested the importance of a CRX binding site within the minimal NXNL1 fragment, we found by mutation analysis that, depending on the context, the CRX site can play a dual role. CONCLUSIONS/SIGNIFICANCE: The regulation of the Nucleoredoxin-like genes involves a CRX responsive element that can act as both as a positive regulator of promoter activity and as a modulator of cell-type specificity.
Document type :
Journal articles
Complete list of metadatas

Cited literature [39 references]  Display  Hide  Download

https://www.hal.inserm.fr/inserm-00527774
Contributor : Katia Marazova <>
Submitted on : Wednesday, October 20, 2010 - 11:38:05 AM
Last modification on : Thursday, July 11, 2019 - 2:10:06 PM
Long-term archiving on: : Friday, January 21, 2011 - 2:38:07 AM

File

journal.pone.0013075.pdf
Publisher files allowed on an open archive

Identifiers

Citation

Sophie Lambard, Sacha Reichman, Cynthia Berlinicke, Marie-Laure Niepon, Olivier Goureau, et al.. Expression of Rod-Derived Cone Viability Factor: Dual Role of CRX in Regulating Promoter Activity and Cell-Type Specificity.. PLoS ONE, Public Library of Science, 2010, 5 (10), pii: e13075. ⟨10.1371/journal.pone.0013075⟩. ⟨inserm-00527774⟩

Share

Metrics

Record views

614

Files downloads

607