Na+ Channel ? Subunits: Overachievers of the Ion Channel Family

Na+ Channel β Subunits: Overachievers of the Ion Channel Family

Voltage-gated Na(+) channels (VGSCs) in mammals contain a pore-forming α subunit and one or more β subunits. There are five mammalian β subunits in total: β1, β1B, β2, β3, and β4, encoded by four genes: SCN1B-SCN4B. With the exception of the SCN1B splice variant, β1B, the β subunits are type I topology transmembrane proteins. In contrast, β1B lacks a transmembrane domain and is a secreted prote...

Human Nedd4 interacts with the human epithelial Na+ channel: WW3 but not WW1 binds to Na+-channel subunits.

The epithelial Na(+) channel (ENaC) regulates Na(+) absorption in epithelial tissues including the lung, colon and sweat gland, and in the distal nephrons of the kidney. When Na(+)-channel function is disrupted, salt and water homoeostasis is affected. The cytoplasmic regions of the Na(+)-channel subunits provide binding sites for other proteins to interact with and potentially regulate Na(+)-c...

Voltage-gated ion channel accessory subunits: sodium, potassium, or both?

Commentary The voltage-gated potassium channel subunit Kv4.2 is a pore-forming alpha subunit of A-type potassium channels. Kv4.2, encoded by the KCND2 gene, is broadly expressed in the central nervous system and is predominantly localized on neuronal dendrites, with increased density on distal dendrites (1). A-type potassium channels are important regulators of neuronal excitability, modulating...

Ion channel activity drives ion channel expression.

Channel a -Subunits

Plant K 1 uptake channel types differ with respect to their voltage, Ca 2 1 , and pH dependence. Here, we constructed recombinant chimeric channels between KST1, a member of the inward-rectifying, acid-activated KAT1 family, and AKT3, a member of the weakly voltage-dependent, proton-blocked AKT2/3 family. The homologous pore regions of AKT3 (amino acids 216 to 287) and KST1 (amino acids 217 to ...