NeuroD

NeuroD is a family of vertebrate basic helix-loop-helix transcription factors that regulate neuronal differentiation and pancreatic development. Members include NEUROD1, NEUROD2, NEUROD4, and NEUROD6; the term NeuroD is often used to refer specifically to NEUROD1. These proteins function as transcription factors that bind E-box sequences as heterodimers with E-proteins, such as E12/E47, to control the expression of genes involved in differentiation, maturation, and cell survival.

In development, NeuroD factors promote neuronal differentiation and maturation and contribute to the formation of specific neuronal populations in the central and peripheral nervous systems. They are also essential for pancreatic islet development and for insulin gene expression in beta cells. NeuroD expression is detected in progenitors and differentiating neurons throughout the CNS, as well as in the retina and pancreatic islets.

Regulation of NeuroD activity involves interactions with other proneural factors and signaling pathways. NeuroD proteins often function in concert with ASCL1 and other basic helix-loop-helix factors to govern cell fate decisions, typically acting downstream of upstream developmental cues and, in some contexts, Notch signaling.

Clinical relevance: Mutations in NEUROD1 have been linked to a monogenic form of diabetes (MODY6) and may contribute to neurodevelopmental disorders in certain contexts. Altered NeuroD expression has been observed in some tumors with neuroendocrine features in research settings. In stem cell biology, NEUROD1 is used to drive neuronal differentiation and, in some protocols, to aid the generation of insulin-producing cells from stem cells.