An element for development: Calcium signaling in mammalian reproduction and development.

Life begins with calcium. It is the language that a sperm cell uses to respond to instructions from the female reproductive tract to alter its swimming pattern and gain the force required to penetrate the outer layers of the oocyte. The first heartbeat transpires from spontaneous calcium oscillations in embryonic cardiomyocytes. The dynamic balance of calcium between auditory hair cells and the fluid they bathe in enables us to hear our first sound, and our interpretation and response to this sound requires rapid calcium flux through neuronal voltage-sensitive calcium channels. Calcium signaling can decode and integrate informational cues from both the chemical and mechanical cellular microenvironment to drive the form and function of many mammalian organ-systems. Here, we highlight roles for the intracellular calcium signal in the reproductive- and developmental- biology of mammals. A greater appreciation of the signaling pathways that initiate and support life has wide-ranging significance for the fields of reproductive science, neonatology and regenerative medicine. Furthermore, as developmental programs are often reactivated in cancer, an improved understanding of the signaling pathways that underpin mammalian development has important implications for cancer research.