Cellular Calcium: Cell Growth and Differentiation

Abstract

Among the various constituents of the living organism, calcium occupies a unique position in the control of cell function, including cell growth and proliferation, as seen in the essential role of calcium in the life cycle of a cell from fertilization, parthenogenesis and mitosis to meiosis. The great concentration gradient of calcium between various compartments, as well as the dynamic equilibrium between rapid exchanges, such as influx and efflux, are no doubt important, in addition to the intrinsic properties of the calcium ion itself. Such dynamic exchanges of calcium across the cell are the basis for excitation and signal transduction. These cellular events are under the control of nutritional factors in the host organism, such as calcium intake. The intracellular factors, such as calmodulin and other calcium-binding proteins, cyclic nucleotides, phospholipids and protein kinase C, also control cell growth and proliferation through interactions with calcium, in conjunction with growth factors, cytokines and oncogenes.