The transcription factor neural retina leucine zipper (Nrl) is a critical determinant of rod
photoreceptor cell fate and a key regulator of rod differentiation. Nrl−/− rod precursors fail to
turn on rod genes and instead differentiate as cones. Furthermore, NRL mutations in
humans cause retinitis pigmentosa. Despite the developmental and clinical significance of
this gene, little is known about the transcriptional regulation of Nrl itself. In this study, we
sought to define the cis-and trans-acting factors responsible for initiation and maintenance of …