The initiation of Otx2 expression in the developing mouse retina requires a unique enhancer and either Ascl1 or Neurog2 activity

We profiled the early initiation of the OTX2 homeobox transcription factor within embryonic E14.5 mouse retinal progenitor cells by electroporation of a GFP-labeled reporter driven by a novel Otx2 enhancer (DHS-4D). This enrichment labeling strategy and subsequent single cell RNA sequencing captured progenitor cells as they become amacrine, horizontal, cone photoreceptor, and ganglion cell types. Using this approach we identified several candidate factors with potential roles in the early regulation of Otx2 expression in the retina, including Ascl1 and Neurog2. Overall design: Single cell RNA sequencing of E14.5 mouse retinal progenitor cells marked with a GFP reporter for an early Otx2 enhancer.