BK channels (big potassium), are large conductance calcium-activated potassium channels,[1] also known as Maxi-K, slo1, or Kca1.1. BK channels are voltage-gated potassium channels that conduct large amounts of potassium ions (K+) across the cell membrane, hence their name, big potassium. These channels can be activated (opened) by either electrical means, or by increasing Ca2+ concentrations in the cell.[2][3] BK channels help regulate physiological processes, such as circadian behavioral rhythms and neuronal excitability.[4] BK channels are also involved in many processes in the body, as it is a ubiquitous channel. They have a tetrameric structure that is composed of a transmembrane domain, voltage sensing domain, potassium channel domain, and a cytoplasmicC-terminal domain, with many X-ray structures for reference. Their function is to repolarize the membrane potential by allowing for potassium to flow outward, in response to a depolarization or increase in calcium levels.
^Zang K, Zhang Y, Hu J, Wang Y (2018). "The Large Conductance Calcium- and Voltage-activated Potassium Channel (BK) and Epilepsy". CNS & Neurological Disorders Drug Targets. 17 (4): 248–254. doi:10.2174/1871527317666180404104055. PMID29623857. S2CID4663325.
^Yuan, P., Leonetti, M., Pico, A., Hsiung, Y., & MacKinnon, R. (2010). Structure of the Human BK Channel Ca2+-Activation Apparatus at 3.0 A Resolution. Science, 329(5988), 182-186. https://dx.doi.org/10.1126/science.1190414
