The protein Bovine Rhodopsin is a photoreceptor that aids in the sensory perception of light stimulus in environments with low light intensity. They are found in the eyes of many organisms, specifically in the tightly packed disks that compose the outer segment of the retina's photoreceptive rod cells. It features a seven-transmembrane helix core and is a G protein-coupled receptor embedded in the lipid bilayer of cell membranes that undergoes a structural change following photoactivation. The and ions that are attached to the aid in this structural change.
Function
Rhodopsin is composed of both a protein molecule known as scotopsin and a cofactor known as retinal. When light hits the retinal, this sparks a series of conformational changes in the opsin embedded in the cell membrane of rods, signaling a signal transduction pathway leading to a conformational change in the opsin. This eventually sends a cGMP to process the incoming light, which close voltage gated cation channels and hypopolarizes the retinal cells. This whole process is known as visual phototransduction.
Disease
The presence of rhodopsin is heavily dependent on the presence of Vitamin A in one's body, so a Vitamin A deficiency can cause a lack of rhodopsin which causes night vision loss. Also there is a disease known as Lebers Congenital Amaurosis which is a rare inherited eye disease that causes photoreceptor cells to not develop properly causing early blindness and reduced function of rhodopsin. A mutation in the rhodopsin can also can cause retinitis pigmentosa, which leads to photoreceptor apoptosis causing decreased vision in low light settings, as well as loss of peripheral vision.
Structural highlights
This is a sample scene created with SAT to by Group, and another to make of the protein. You can make your own scenes on SAT starting from scratch or loading and editing one of these sample scenes.
