Cyclic nucleotide-gated channel alpha 2

Cyclic nucleotide-gated channel alpha 2 (CNGA2) is a protein that in humans is encoded by the CNGA2 gene. This protein is a subunit of a cyclic nucleotide-gated ion channel that plays a crucial role in the initiation of sensory transduction in the olfactory system.

Structure

The CNGA2 protein is a member of the cyclic nucleotide-gated (CNG) channel family. These channels are nonselective cation channels that are structurally related to voltage-gated ion channels. The CNGA2 subunit is composed of six transmembrane segments (S1-S6), a pore-forming region between S5 and S6, and a cyclic nucleotide-binding domain (CNBD) in the C-terminus.

Function

CNGA2 channels are essential for the conversion of odorant-induced changes in cyclic nucleotide levels into an electrical signal. They are directly activated by the binding of cyclic nucleotides, including cyclic AMP (cAMP) and cyclic GMP (cGMP), to the CNBD. This binding leads to the opening of the channel and the influx of cations, including calcium and sodium, into the cell.

Clinical significance

Mutations in the CNGA2 gene have been associated with olfactory dysfunction, including anosmia (the inability to perceive odor) and hyposmia (reduced ability to perceive odor).

See also

• Cyclic nucleotide-gated ion channel
• Olfactory system
• Sensory transduction