Description
NeuroD1 encodes a basic helix-loop-helix transcription factor involved in the development of neural and endocrine structures. NeuroD1 mRNA is highly abundant in the adult mammalian pineal gland and exhibits a developmental expression pattern similar to the retina. This is consistent with the common evolutionary origin of pinealocytes and retinal photoreceptors. Pinealocytes and retinal photoreceptors express a shared set of phototransduction genes and submammalian pinealocytes are photosensitive. In contrast to the retina, the pineal gland is a relatively homogeneous structure, composed 95% of pinealocytes. This makes the pineal gland a particularly useful model for understanding photoreceptor cell biology. The loss of NeuroD1 in the retina results in progressive photoreceptor degeneration and the molecular mechanisms underlying this retinal degeneration phenotype remain unknown. Similarly, the role that NeuroD1 plays in the pineal gland is unknown.