Cyclic nucleotide gated channel beta 3

Cyclic nucleotide gated channel beta 3 (CNG3) is a protein that in humans is encoded by the CNGB3 gene. This protein is a subunit of a naturally occurring neuronal channel complex that is activated by cAMP and cGMP. The protein is found in the retina and is essential for normal vision.

Function

CNG3 is a subunit of the cyclic nucleotide-gated (CNG) channels, which are nonselective cation channels that are activated by cyclic nucleotides. CNG channels are crucial for processes such as vision and olfaction. The CNG3 subunit is expressed in the cone photoreceptor cells in the retina and is involved in the cone phototransduction pathway.

Clinical significance

Mutations in the CNGB3 gene are associated with achromatopsia (ACHM3), a rare inherited vision disorder. ACHM3 is characterized by decreased visual acuity, extreme light sensitivity, and the absence of color discrimination.

Structure

The CNG3 subunit is part of the larger CNG channel complex. It is composed of six transmembrane segments (S1-S6), a pore-forming region, and a cyclic nucleotide-binding domain (CNBD). The CNBD is located in the C-terminal cytoplasmic region of the protein.

See also

• Cyclic nucleotide-gated ion channel
• Achromatopsia

External links

• GeneReviews/NCBI/NIH/UW entry on Achromatopsia