Regulation of gene expression by Ca2+ signals in neuronal cells

Calcium ions are ubiquitous second messengers that control diverse cellular functions. The versatility of Ca2+ arises both from the ability of cells to employ a range of mechanisms to generate stimulus - induced Ca2+ signals with defined characteristics and the existence of a large repertoire of Ca2+ receptive proteins that mediate the effects of Ca2+. In neurons, the regulation of gene expression by electrical activity-induced increases in Ca2+ is critical for the longa-term maintenance of neuronal adaptive responses. Different patterns of synaptic activity are able to generate Ca2+ signals varying in their amplitude, temporal profile, spatial properties and source or site of entry. The information embedded in Ca2+ signals is decoded by Ca2+-responsive transcriptional regulators, including protein kinases, phosphatases and transcription factors, with differing Ca2+ sensitivities, kinetics of activation and deactivation, and subcellular localisation. The coordinated control of many transcriptional regulators by Ca2+ signals determines the qualitative and quantitative nature of the genomic response. (C) 2002 Elsevier Science B.V. All rights reserved.