ABSTRACT
The growth and differentiation of cells is accompanied by major changes in ion fluxes through the surface and intracellular membranes. These ion fluxes generate membrane potential and ion concentration gradients that affect growth and differentiation (Leffert, 1980; Whitfield, 1995). Although a causal relationship between ion fluxes and a cellular event is usually difficult to establish, there are several well-documented cases where monovalent or divalent cations play an instructive role in the regulation of gene expression, leading to developmental changes in the synthesis of specific gene products.
