Acid-sensing ion channel

Acid-sensing sodium channel
Structure of acid-sensing ion channel 1.[1]
Identifiers
Symbol	ASC
Pfam	PF00858
InterPro	IPR001873
PROSITE	PDOC00926
SCOP2	2qts / SCOPe / SUPFAM
TCDB	1.A.6
OPM superfamily	181
OPM protein	4fz1
Available protein structures: Pfam   structures / ECOD   PDB RCSB PDB; PDBe; PDBj PDBsum structure summary

Acid-sensing ion channels (ASICs) are neuronal voltage-insensitive sodium channels activated by extracellular protons permeable to Na⁺. ASIC1 also shows low Ca²⁺ permeability.^[2] ASIC proteins are a subfamily of the ENaC/Deg superfamily of ion channels. These genes have splice variants that encode for several isoforms that are marked by a suffix. In mammals, acid-sensing ion channels (ASIC) are encoded by five genes that produce ASIC protein subunits: ASIC1, ASIC2, ASIC3, ASIC4, and ASIC5.^[3] Three of these protein subunits assemble to form the ASIC, which can combine into both homotrimeric and heterotrimeric channels typically found in both the central nervous system and peripheral nervous system.^[2] However, the most common ASICs are ASIC1a and ASIC1a/2a and ASIC3. ASIC2b is non-functional on its own but modulates channel activity when participating in heteromultimers and ASIC4 has no known function. On a broad scale, ASICs are potential drug targets due to their involvement in pathological states such as retinal damage, seizures, and ischemic brain injury.^[4][5]