Guinea pig Anti-KCNMA1 (K_Ca1.1) (1097-1196) Antibody

High conductance voltage and Ca²⁺-activated K⁺ channels (also known as BK or Slo1 channels) are a family of K⁺ channels involved in various physiological processes including neuronal excitability and smooth muscle contraction.

K_Ca1.1 channel, also known as KCNMA1, is a member of the BK family and like other BK channels it is comprised of four identical subunits. Each unit consists of seven transmembrane segments and a large intracellular C-terminus. Transmembrane segments S1 to S4 form the channel’s voltage sensor; S5, S6 and the intervening amino acids form the pore and selectivity filter. The C-terminus forms a large cytoplasmic domain. This large domain accounts for two-thirds of the entire channel and is believed to contain the domain for Ca²⁺ binding. Two tandem C-terminal regulator of K⁺ conductance (RCK) domains from each of four channel subunits form a gating ring at the intracellular membrane surface. A sequence of amino acids that is known as the Ca²⁺ bowl, and is located within the second of the tandem RCK domains, creates four Ca²⁺ binding sites on the outer perimeter of the gating ring between RCK domains.

K_Ca1.1 is regulated, both by membrane depolarization and increased intracellular Ca²⁺ levels which cause the channel to open. This causes subsequent membrane hyperpolarization that closes voltage- and Ca²⁺-gated channels thus making K_Ca1.1 a negative feedback regulator for electrical excitation¹.

K_Ca1.1 is implicated in the pathogenesis of several diseases. Elevated levels of K_Ca1.1 mRNA are detected in malignant pleural mesothelioma patients compared with control patients². Also, blocking K_Ca1.1 reduces the symptoms of fibroblast-like synoviocytes in rheumatoid arthritis animal models.