Acid-sensing ion channel 2 (ASIC2) also known as amiloride-sensitive cation channel 1, neuronal (ACCN1) or brain sodium channel 1 (BNaC1) is a protein that in humans is encoded by the ASIC2 gene. The ASIC2 gene is one of the five paralogous genes that encode proteins that form trimeric acid-sensing ion channels (ASICs) in mammals. [5] The cDNA of this gene was first cloned in 1996. [6] [7] [8] [9] The ASIC genes have splicing variants that encode different proteins that are called isoforms.
These genes are mainly expressed in the central and peripheral nervous system.
ASICs can form both homotrimeric (meaning composed of three identical subunits) and heterotrimeric channels. [10] [11]
This gene encodes a member of the ASIC/ENaC superfamily of proteins. [12] The members of this family are amiloride-sensitive sodium channels that contain intracellular N and C termini, 2 hydrophobic transmembrane (TM) regions, and a large extracellular loop, which has many cysteine residues with conserved spacing. The TM regions are generally symbolized as TM1 (clone to N-terminus) and TM2 (close to C-terminus).
The pore of the channel through which ions selectively flow from the extracellular side into the cytoplasm is formed by the three TM2 regions of the trimer. [5]
Cystic fibrosis transmembrane conductance regulator (CFTR) is a membrane protein and anion channel in vertebrates that is encoded by the CFTR gene.
The renal outer medullary potassium channel (ROMK) is an ATP-dependent potassium channel (Kir1.1) that transports potassium out of cells. It plays an important role in potassium recycling in the thick ascending limb (TAL) and potassium secretion in the cortical collecting duct (CCD) of the nephron. In humans, ROMK is encoded by the KCNJ1 gene. Multiple transcript variants encoding different isoforms have been found for this gene.
The epithelial sodium channel(ENaC), (also known as amiloride-sensitive sodium channel) is a membrane-bound ion channel that is selectively permeable to sodium ions (Na+). It is assembled as a heterotrimer composed of three homologous subunits α or δ, β, and γ, These subunits are encoded by four genes: SCNN1A, SCNN1B, SCNN1G, and SCNN1D. The ENaC is involved primarily in the reabsorption of sodium ions at the collecting ducts of the kidney's nephrons. In addition to being implicated in diseases where fluid balance across epithelial membranes is perturbed, including pulmonary edema, cystic fibrosis, COPD and COVID-19, proteolyzed forms of ENaC function as the human salt taste receptor.
The sodium-hydrogen antiporter 1 (NHE-1) also known as sodium/hydrogen exchanger 1 or SLC9A1 is an isoform of sodium–hydrogen antiporter that in humans is encoded by the SLC9A1 gene.
Protein Interacting with C Kinase - 1 is a protein that in humans is encoded by the PICK1 gene.
The alpha-2A adrenergic receptor, also known as ADRA2A, is an α2 adrenergic receptor, and also denotes the human gene encoding it.
The SCNN1B gene encodes for the β subunit of the epithelial sodium channel ENaC in vertebrates. ENaC is assembled as a heterotrimer composed of three homologous subunits α, β, and γ or δ, β, and γ. The other ENAC subunits are encoded by SCNN1A, SCNN1G, and SCNN1D.
The SCNN1A gene encodes for the α subunit of the epithelial sodium channel ENaC in vertebrates. ENaC is assembled as a heterotrimer composed of three homologous subunits α, β, and γ or δ, β, and γ. The other ENAC subunits are encoded by SCNN1B, SCNN1G, and SCNN1D.
The SCNN1G gene encodes for the γ subunit of the epithelial sodium channel ENaC in vertebrates. ENaC is assembled as a heterotrimer composed of three homologous subunits α, β, and γ or δ, β, and γ. The other ENAC subunits are encoded by SCNN1A, SCNN1B, and SCNN1D.
Acid-sensing ion channel 1 (ASIC1) also known as amiloride-sensitive cation channel 2, neuronal (ACCN2) or brain sodium channel 2 (BNaC2) is a protein that in humans is encoded by the ASIC1 gene. The ASIC1 gene is one of the five paralogous genes that encode proteins that form trimeric acid-sensing ion channels (ASICs) in mammals. The cDNA of this gene was first cloned in 1996. The ASIC genes have splicing variants that encode different proteins that are called isoforms.
Membrane-associated guanylate kinase, WW and PDZ domain-containing protein 1 is an enzyme that in humans is encoded by the MAGI1 gene.
Acid-sensing ion channel 3 (ASIC3) also known as amiloride-sensitive cation channel 3 (ACCN3) or testis sodium channel 1 (TNaC1) is a protein that in humans is encoded by the ASIC3 gene. The ASIC3 gene is one of the five paralogous genes that encode proteins that form trimeric acid-sensing ion channels (ASICs) in mammals. The cDNA of this gene was first cloned in 1998. The ASIC genes have splicing variants that encode different proteins that are called isoforms.
Sodium channel protein type 8 subunit alpha also known as Nav1.6 is a membrane protein encoded by the SCN8A gene. Nav1.6 is one sodium channel isoform and is the primary voltage-gated sodium channel at each node of Ranvier. The channels are highly concentrated in sensory and motor axons in the peripheral nervous system and cluster at the nodes in the central nervous system.
The SCNN1D gene encodes for the δ (delta) subunit of the epithelial sodium channel ENaC in vertebrates. ENaC is assembled as a heterotrimer composed of three homologous subunits α, β, and γ or δ, β, and γ. The other ENAC subunits are encoded by SCNN1A, SCNN1B, and SCNN1G.
G protein-activated inward rectifier potassium channel 3 is a protein that in humans is encoded by the KCNJ9 gene.
Potassium voltage-gated channel subfamily B member 2 is a protein that in humans is encoded by the KCNB2 gene. The protein encoded by this gene is a voltage-gated potassium channel subunit.
Psalmotoxin (PcTx1) is a spider toxin from the venom of the Trinidad tarantula Psalmopoeus cambridgei. It selectively blocks Acid Sensing Ion Channel 1-a (ASIC1a), which is a proton-gated sodium channel.
Acid-sensing ion channels (ASICs) are neuronal voltage-insensitive sodium channels activated by extracellular protons permeable to Na+. ASIC1 also shows low Ca2+ permeability. 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. 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. 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.
Acid-sensing ion channel 4 (ASIC4) also known as amiloride-sensitive cation channel 4 (ACCN4) is a protein that in humans is encoded by the ASIC4 gene. The ASIC4 gene is one of the five paralogous genes that encode proteins that form trimeric acid-sensing ion channels (ASICs) in mammals. The cDNA of this gene was first cloned in 2000. The ASIC genes have splicing variants that encode different proteins that are called isoforms.
ASIC5 gene is one of the five paralogous genes that encode proteins that form trimeric Acid-sensing ion channels (ASICs) in mammals. Aliases previously used for this gene include ACCN5 and BASIC. The protein encoded by this gene does not appear to be acid responsive. The cDNA coding for this protein was first characterized in 2000. The ASIC genes have splicing variants that encode different proteins that are called isoforms.