Conditional knockdown of DNA methyltransferase-1 (Dnmt1) reveals a key role of retinal pigment epithelium integrity in photoreceptor outer segment morphogenesis
Ontology highlight
ABSTRACT:
ORGANISM(S): Mus musculus
SUBMITTER: Matthew Brooks
PROVIDER: E-GEOD-43951 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Publications
Conditional knockdown of DNA methyltransferase 1 reveals a key role of retinal pigment epithelium integrity in photoreceptor outer segment morphogenesis.
Nasonkin Igor O IO Merbs Shannath L SL Lazo Kevin K Oliver Verity F VF Brooks Matthew M Patel Krushangi K Enke Raymond A RA Nellissery Jacob J Jamrich Milan M Le Yun Z YZ Bharti Kapil K Fariss Robert N RN Rachel Rivka A RA Zack Donald J DJ Rodriguez-Boulan Enrique J EJ Swaroop Anand A
Development (Cambridge, England) 20130213 6
Dysfunction or death of photoreceptors is the primary cause of vision loss in retinal and macular degenerative diseases. As photoreceptors have an intimate relationship with the retinal pigment epithelium (RPE) for exchange of macromolecules, removal of shed membrane discs and retinoid recycling, an improved understanding of the development of the photoreceptor-RPE complex will allow better design of gene- and cell-based therapies. To explore the epigenetic contribution to retinal development we ...[more]
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Project description:To explore the epigenetic contribution to retinal development, we generated conditional knockout alleles of DNA methytransferase-1 (Dnmt1) mediated by Rx-Cre in mice. The results demonstrate a unique function of DNMT1-mediated DNA methylation in controlling RPE apicobasal polarity and neural retina differentiation.
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Project description:Retinal photoreceptors undergo daily renewal of their distal outer segments, a process indispensable for maintaining retinal health. Photoreceptor Outer Segment (POS) phagocytosis occurs as a daily peak, roughly about one hour after light onset. However, the underlying cellular and molecular mechanisms which initiate this process are still unknown. Here we show that, under constant darkness, mice deficient for core circadian clock genes (Per1 and Per2), lack a daily peak in POS phagocytosis. By qPCR analysis we found that core clock genes were rhythmic over 24h in both WT and Per1, Per2 double mutant whole retinas. More precise transcriptomics analysis of laser capture microdissected WT photoreceptors revealed no differentially expressed genes between time-points preceding and during the peak of POS phagocytosis. By contrast, we found that microdissected WT retinal pigment epithelium (RPE) had a number of genes that were differentially expressed at the peak phagocytic time-point compared to adjacent ones. We also found a number of differentially expressed genes in Per1, Per2 double mutant RPE compared to WT ones at the peak phagocytic time-point. Finally, based on STRING analysis we found a group of interacting genes which potentially drive POS phagocytosis in the RPE. This potential pathway consists of genes such as: Pacsin1, Syp, Camk2b and Camk2d among others. Our findings indicate that Per1 and Per2 are necessary clock components for driving POS phagocytosis and suggest that this process is transcriptionally driven by the RPE.
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