CALCIUM REGULATION OF IMMEDIATE-EARLY RESPONSE GENES

A rise in intracellular Ca2+ concentration induces the transcription o f a number of eukaryotic genes through transcription factors interacti ng with calcium response elements. Immediate-early response genes enco de proteins that couple extracellular signals to phenotypic alteration s by modulating the transcription rates of target genes. Since the act ivation of early response genes occurs within minutes, this class of g enes has served as a paradigm for the understanding of the molecular m echanisms by which external signals are conveyed to the nucleus to ind uce changes in genetic programs. In this review, we outline the recent information which has been gained specifically on how the Ca2+ messen ger system modulates early response gene expression. We also discuss s ome lines of research with the intent of linking closer Ca2+ homeostas is and gene expression studies which in the past have followed their o wn separate routes.