Recoverin and rhodopsin kinase.

The majority of proteins involved in vertebrate phototransduction are expressed specifically in photoreceptors. Recoverin and rhodopsin kinase are expressed primarily in retinal photoreceptors and they interact with each other in a Ca2+-dependent manner. This Ca2+-dependent interaction has been studied extensively in vitro. Experiments utilizing animal models and electrophysiological approaches have started to provide important insight regarding its invivo function. Recoverin can be viewed as a negative regulator of rhodopsin kinase in vertebrate phototransduction. This interaction imparts a negative feedback loop at the receptor level and may play an important role in light adaptation and in recovery.