CNGB3 : cyclic nucleotide gated channel subunit beta 3
Description
The CNGB3 (cyclic nucleotide gated channel subunit beta 3) is a protein-coding gene located on chromosome 8.
The CNGB3 gene provides instructions for making one part (the beta subunit) of the cone photoreceptor cyclic nucleotide-gated (CNG) channel. These channels are exclusively found in light-detecting (photoreceptor) cells called cones, which are located in a specialized tissue at the back of the eye known as the retina. Cones provide vision in bright light (daylight vision), including color vision. Other photoreceptor cells, called rods, provide vision in low light (night vision). CNG channels are openings in the cell membrane that transport positively charged atoms (cations) into cells. In cones, CNG channels remain open under dark conditions, allowing cations to flow in. When light enters the eye, it triggers the closure of these channels, stopping the inward flow of cations. This change in cation transport alters the cone's electrical charge, which ultimately generates a signal that is interpreted by the brain as vision. This process of translating light into an electrical signal is called phototransduction.
CNGB3 plays a vital role in visual signal transduction, particularly in the cones responsible for color vision. It acts as a component of the cGMP-gated cation channel, mediating the conversion of light into electrical signals. This process is triggered by changes in cGMP levels, which in turn regulate the channel's opening and closing. The channel's permeability to cations like sodium and calcium allows for depolarization of the cone cells, leading to neurotransmitter release and ultimately, the perception of light. Additionally, CNGB3 contributes to the enhanced sensitivity of the channel to specific compounds and influences its interaction with other subunits, further highlighting its critical role in visual signaling.
CNGB3 is also known as ACHM1.
