Expression of Orai genes and I(CRAC) activation in the human retinal pigment epithelium.

The retinal pigment epithelium (RPE) fulfills a large variety of tasks that are important for visual function. Many of these tasks, such as phagocytosis, growth factor secretion, or transepithelial ion transport, are regulated by increases in intracellular Ca²(+) as second-messenger. Despite the multitude of Ca²(+)-dependently regulated functions, only few Ca²(+) channels have been described so far in the RPE to couple Ca²(+) conductance and Ca²(+) signaling.