Control of photoreceptor proteins by Ca2+
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Updated: Aug 12, 2026

Preparation of Living Isolated Vertebrate Photoreceptor Cells for Fluorescence Imaging
Published on: June 22, 2011
1Institut für Biologische Informationsverarbeitung, Forschungszentrum Jülich, Germany.
Abstract:
A decrease of cytoplasmic Ca(2+)-concentration in vertebrate photoreceptor cells after illumination is necessary for light adaptation. Although the mechanisms of adaptation is not completely understood, several Ca(2+)-dependent cellular processes have been discovered. Some involve calcium-binding proteins like recoverin, guanylyl cyclase-activating protein and calmodulin, and their target proteins rhodopsin kinase, guanylyl cyclase, the cGMP-gated channel, and NO synthase. The activity of several enzymes or channels is directly controlled by Ca2+ and does not involve calcium-binding proteins. These proteins are pyrophosphatase, protein kinase C and the cGMP-gated channel.
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