Protein: Calcium-activated potassium channel subunit beta-1 (BK channel subunit beta-1) (BKbeta) (BKbeta1) (Calcium-activated potassium channel, subfamily M subunit beta-1) (Calcium-activated potassium channel subunit beta) (Charybdotoxin receptor subunit beta-1) (K(VCA)beta-1) (Maxi K channel subunit beta-1) (Slo-beta-1) (Slo-beta) (Q8CAE3)
Organism: Mus musculus (Mouse)
Function: Regulatory subunit of the calcium activated potassium KCNMA1 (maxiK) channel. Modulates the calcium sensitivity and gating kinetics of KCNMA1, thereby contributing to KCNMA1 channel diversity. Increases the apparent Ca(2+)/voltage sensitivity of the KCNMA1 channel. It also modifies KCNMA1 channel kinetics and alters its pharmacological properties. It slows down the activation and the deactivation kinetics of the channel. Acts as a negative regulator of smooth muscle contraction by enhancing the calcium sensitivity to KCNMA1. Its presence is also a requirement for internal binding of the KCNMA1 channel opener dehydrosoyasaponin I (DHS-1) triterpene glycoside and for external binding of the agonist hormone 17-beta-estradiol (E2). Increases the binding activity of charybdotoxin (CTX) toxin to KCNMA1 peptide blocker by increasing the CTX association rate and decreasing the dissociation rate.
Subcellular location: Membrane; Multi-pass membrane protein.
Sequence: MGKKLVMAQKRGETRALCLGVAMVVCAAITYYVLGTTVLPLYQKSVWTQESICHLIETNIKDQEELEGKKVPQYPCLWVNVSAVGRWAMLYHTEDTRDQNQQCSYIPRNLDNYQTALADVKKVRANFYKHHEFYCLSAPQVNETSVVYQRLYGPQVLLFSFFWPTFLLTGGLLLIAMVKLNRSLSILAAQK
InterPro domains: - IPR003930: Potassium channel, calcium-activated, BK, beta subunit (family) [3-190]
Interaction partners: - Calcium-activated potassium channel subunit alpha-1
- Calcium-activated potassium channel subunit beta-4
- Potassium channel subfamily U member 1 current)
- Small conductance calcium-activated potassium channel protein 1
- Intermediate conductance calcium-activated potassium channel protein 4
- Small conductance calcium-activated potassium channel protein 2
- Small conductance calcium-activated potassium channel protein 3
- cAMP-dependent protein kinase catalytic subunit alpha
- cAMP-dependent protein kinase catalytic subunit beta
- cGMP-dependent protein kinase 1
Gene Ontology annotations:
Molecular Function (MF): GO:0003674 (molecular function), GO:0098772 (molecular function regulator activity), GO:0005488 (binding), GO:0016247 (channel regulator activity), GO:0005515 (protein binding), GO:0099106 (ion channel regulator activity), GO:0015459 (potassium channel regulator activity)
Biological Process (BP): GO:0008150 (biological process), GO:0009987 (cellular process), GO:0023052 (signaling), GO:0051179 (localization), GO:0051234 (establishment of localization), GO:0007267 (cell-cell signaling), GO:0007154 (cell communication), GO:0099536 (synaptic signaling), GO:0006810 (transport), GO:0006811 (monoatomic ion transport), GO:0099537 (trans-synaptic signaling), GO:0006812 (monoatomic cation transport), GO:0098916 (anterograde trans-synaptic signaling), GO:0030001 (metal ion transport), GO:0007268 (chemical synaptic transmission), GO:0006813 (potassium ion transport)
Cellular Component (CC): GO:0005575 (cellular component), GO:0110165 (cellular anatomical entity), GO:0071944 (cell periphery), GO:0016020 (membrane), GO:0005886 (plasma membrane)