Both rod and cone photoreceptors are critical for mammalian vision yet they have important functional differences. In this study, we investigate patterns of DNA methylation and chromatin accessibility in mouse rods and cones. Unexpectedly, we find that a substantial fraction of hypo-methylated regions in the rod methylome are in inaccessible chromatin. These regions show marks of active regulatory regions earlier in neuronal development and could remain undermethylated in adult rods due to their highly compact chromatin. We further identify rod- and cone-enriched regions of accessible chromatin that correspond with cell type-specificity of nearby photoreceptor gene expression. We predict novel DNA signatures of rod and cone specificity and show that NR2E3 function is necessary for rods to gain their complete ensemble of epigenomic features. Taken together, our data capture the epigenomic landscapes of retinal rods and cones, including differences relevant to chromatin structure and photoreceptor biology. SOURCE: Alisa Mo (amo4@jhmi.edu) - Jeremy Nathans Johns Hopkins University School of Medicine

Pluto Bioinformatics

GSE72550: Epigenomic Landscapes of Retinal Rods and Cones