*Melanopsin: in vertebrate retina, mediates pupillary reflex,  involved in regulation of circadian rhythms
*Photopsin: reception of various colors of light in the cone cells of vertebrate retina
*Rhodopsin: green-blue light reception in the rod cells of vertebrate retina
*Protein Kinase C: mediates photoreceptor deactivation, and retinal  degeneration
*OPN5: sensitive to UV-light