Calcium-driven regulation of voltage-sensing domains in BK channels

• DOI: 10.7554/elife.44934
• Publication Date: 2019-09-11T12:00:18Z
• Authors: Yenisleidy Lorenz...; Willy Carrasquel-...; Karen Castillo; Osvaldo Alvarez; Ramon Latorre
• Keywords: BK channel; Crosstalk

Allosteric interactions between the voltage-sensing domain (VSD), Ca2+-binding sites, and pore govern mammalian Ca2+- voltage-activated K+ (BK) channel opening. However, functional relevance of crosstalk mechanisms on BK gating is still debated. We examined energetic interaction Ca2+ binding VSD activation by investigating effects internal currents. Our results indicate that sensor occupancy has a strong impact through coordinated mechanism in which to single α-subunit affects all VSDs equally. Moreover, two distinct high-affinity sites contained C-terminus domains, RCK1 RCK2, contribute equally decrease free energy necessary activate VSD. conclude voltage-dependent opening channels modulated great extent sensors VSDs.