Ca2+ channels and signalling in cilia and flagella.

Ca(2+) plays a key role in the regulation of ciliary and flagellar movement. This article focuses on the initial steps of this regulation: how and where Ca(2+) enters cilia and flagella to trigger specific changes in axonemal motility. This knowledge is fundamental for understanding the sites, molecular targets and mechanisms of action of Ca(2+) within the cilium of flagellum.