TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*8.A.14.1.1









Sloβ auxiliary subunit

Eukaryota
Metazoa
Sloβ from Mus musculus (Q9JIN6)
*8.A.14.1.2









Smooth muscle and brain Ca2+-activated K+ channel β-subunit, Slo-β (β1); confers increased Ca2+ and voltage sensitivity (Tseng-Crank et al., 1996). A steroid interaction site is in transmembrane domain 2 of the potassium (BK) channel accessory β-subunit (Bukiya et al., 2011). A Long-chain omega-3 polyunsaturated fatty acids such as docosahexaenoic acid (DHA), found in oily fish, lower blood pressure by activating vascular BK channels made of Slo1 β1 subunits. Neuronal Slo1 β4 channels were just as well activated by DHA as vascular Slo1 β1 channels, but the stimulatory effect of DHA was much smaller in Slo1 β2, Slo1 LRRC26 (γ1), and Slo1 channels without auxiliary subunits.  Residues responsible for this response to DHA were identified (Hoshi et al. 2013). BK beta1 TMS2 is necessary for this subunit to enable ethanol-induced inhibition of myocyte BK channels and cerebral artery constriction at physiological Ca2+ and voltages (Kuntamallappanavar and Dopico 2017). After moderate or heavy drinking, the ethanol concentration in the blood is 30 - 60 mM.

Eukaryota
Metazoa
Sloβ1 of Homo sapiens (Q16558)
*8.A.14.1.3









Auxillary β-subunit (β2) of voltage-dependent and Ca2+ sensitive K+ channel (MaxiK; 1.A.1.3.2) The increased current reduces excitability (Wallner et al., 1999). 44% identical to TC#8.A.14.1.4). Full=BK channel subunit beta-2; Short=BKbeta2; Short=Hbeta2; AltName: Full=Calcium-activated potassium channel, subfamily M subunit beta-2; AltName: Full=Charybdotoxin receptor subunit beta-2; AltName: Full=Hbeta3; AltName: Full=K(VCA)beta-2; AltName: Full=Maxi K channel subunit beta-2; AltName: Full=Slo-beta-2. Coexpression of KCNMB2 with the human pore-forming alpha subunit of the large conductance voltage and Ca2+-activated K+ channel (hSlo) yields inactivating currents similar to those observed in hippocampal neurons.  β2 not only influences hSlo currents but also limits hSlo surface expression levels via an endocytic mechanism (Zarei et al. 2007).

Eukaryota
Metazoa
β2 of Homo sapiens (Q9Y691)
*8.A.14.1.4









Auxillary β subunit (β3) of voltage-dependent and Ca2+ sensitive K+ channel (MaxiK; 1.A.1.3.2) (Brenner et al., 2000).  44% identical to TC# 8.A.14.1.3.

Eukaryota
Metazoa
β3 of Homo sapiens (Q9NPA1)