Cyclic nucleotide-gated channel alpha 3

Cyclic nucleotide-gated channel alpha 3 (CNGA3) is a protein that in humans is encoded by the CNGA3 gene. This protein is a subunit of a cyclic nucleotide-gated ion channel that plays a crucial role in the phototransduction pathway of the cone photoreceptor cells in the retina.

Function

The CNGA3 protein is an integral membrane protein that forms a voltage-independent ion channel activated by the binding of cyclic nucleotides. This ion channel is a complex composed of a homotetramer or a heterotetramer of different subunits, including the alpha-3 subunit. The CNGA3 subunit can bind cyclic GMP and cyclic AMP, and is involved in the depolarization of photoreceptor cells in the retina.

Clinical significance

Mutations in the CNGA3 gene are associated with achromatopsia (ACHM2), a rare congenital disorder characterized by the absence of color vision. Patients with ACHM2 have difficulty distinguishing colors, decreased visual acuity, and increased sensitivity to light.

See also

• Cyclic nucleotide-gated ion channel
• Achromatopsia
• Cone photoreceptor