Inhibitors of DNA binding in neural cell proliferation and differentiation.

Id proteins function as negative regulators of bHLH transcription factors by disrupting the homo- and/or hetero-dimerization of bHLH-bHLH transcription factors. Recent data from in vitro and in vivo studies have revealed the complex biological functions of Id proteins in the regulation of cell differentiation, the cell cycle, and cell survival. Several advances in the understanding of Id-regulated neurogenesis have been made. Basically, Id proteins are positive regulators of neural cell proliferation, are required for neural cell cycle progression, and also play a role in the timing of oligodendroglial differentiation. Here we summarize recent findings regarding the regulation of Id proteins in neural cells and discuss the possible mechanisms of Id-regulated neurogenesis.