Several NRs including PNR, TRβ2, RORs, TLX, RXRs, RARs, ERRs, COUPTFs and Reverbs are implicated in retinal development and function.41 Interestingly, PPARs are also implicated in ocular diseases, including retinopathies, diabetic retinopathy and age-related macular degeneration.58 Therefore, our evidence for novel heterodimeric interactions of PNR and PPARγ indicates a potentially important intersection of these regulators in retina or other tissues. Here, RARS1 is linked to diabetic retinopathy.