CACNG2
Description
The CACNG2 (calcium voltage-gated channel auxiliary subunit gamma 2) is a protein-coding gene located on chromosome 22.
CACNG2, also known as stargazin, is a protein encoded by the CACNG2 gene in humans. It is one of the five subunits that make up L-type calcium channels, specifically the gamma subunit. CACNG2 is an integral membrane protein thought to stabilize the calcium channel in an inactive (closed) state. It shares similarity with the mouse stargazin protein, where mutations have been linked to absence seizures. CACNG2 is a member of the neuronal calcium channel gamma subunit gene subfamily belonging to the PMP-22/EMP/MP20 family. Beyond its role in calcium channel regulation, CACNG2 is involved in the transportation of AMPA receptors to the synaptic membrane and the regulation of their receptor rate constants through its extracellular domain. Its high expression throughout the cerebral cortex suggests a crucial role in learning within these areas due to the importance of AMPA receptors in LTP. Disruptions in CACNG2 have been implicated in autism. CACNG2 interacts with several proteins, including GRIA4, DLG4, and MAGI2.
CACNG2 regulates the trafficking and gating properties of AMPA-selective glutamate receptors (AMPARs). It facilitates their localization to the cell membrane and synapses and fine-tunes their gating behavior by decelerating their activation, deactivation, and desensitization rates. Notably, CACNG2 does not exhibit subunit-specific regulation of AMPARs and influences all AMPAR subunits. Additionally, it is believed to stabilize the calcium channel in an inactive (closed) state.
CACNG2 is also known as MRD10.
