Calcium-activated potassium channel beta subunit explained

Symbol:	CaKB
CaKB
Pfam:	PF03185
Interpro:	IPR003930
Scop:	1jo6
Tcdb:	8.A.14

In molecular biology, the calcium-activated potassium channel beta subunit is a family of proteins comprising the beta subunits of calcium-activated potassium channels.

The functional diversity of potassium channels can arise through homo- or hetero-associations of alpha subunits or association with auxiliary cytoplasmic beta subunits. The beta subunit (which is thought to possess 2 transmembrane domains) increases the calcium sensitivity of the BK channel.^[1] It does this by enhancing the time spent by the channel in burst-like open states. However, it has little effect on the durations of closed intervals between bursts, or on the numbers of open and closed states entered during gating.^[2]

Notes and References

1. McManus OB, Helms LM, Pallanck L, Ganetzky B, Swanson R, Leonard RJ . Functional role of the beta subunit of high conductance calcium-activated potassium channels . Neuron . 14 . 3 . 645–50 . March 1995 . 7695911 . 10.1016/0896-6273(95)90321-6. 6093600 . free .
2. Nimigean CM, Magleby KL . The beta subunit increases the Ca2+ sensitivity of large conductance Ca2+-activated potassium channels by retaining the gating in the bursting states . J. Gen. Physiol. . 113 . 3 . 425–40 . March 1999 . 10051518 . 2222905 . 10.1085/jgp.113.3.425.