Database of articles cited by EMDB/PDB/SASBDB data

Keywords
Structure methods	All X-ray diffraction NMR electron microscopy small angle scattering neutron diffraction fiber diffraction powder diffraction infrared spectroscopy EPR fluorescence transfer theoretical model Hybrid
Author
Journal
IF	>30 >20 >10 >5 all

Title	Ball-and-chain inactivation of a human large conductance calcium-activated potassium channel.
Journal, issue, pages	Nat Commun, Vol. 16, Issue 1, Page 1769, Year 2025
Publish date	Feb 19, 2025
Authors	Shubhangi Agarwal / Elizabeth D Kim / Sangyun Lee / Alexander Simon / Alessio Accardi / Crina M Nimigean /
PubMed Abstract	BK channels are large-conductance calcium (Ca)-activated potassium channels crucial for neuronal excitability, muscle contraction, and neurotransmitter release. The pore-forming (α) subunits co- ...BK channels are large-conductance calcium (Ca)-activated potassium channels crucial for neuronal excitability, muscle contraction, and neurotransmitter release. The pore-forming (α) subunits co-assemble with auxiliary (β and γ) subunits that modulate their function. Previous studies demonstrated that the N-termini of β2-subunits can inactivate BK channels, but with no structural correlate. Here, we investigate BK β2-subunit inactivation using cryo-electron microscopy, electrophysiology and molecular dynamics simulations. We find that the β2 N-terminus occludes the pore only in the Ca-bound open state, via a ball-and-chain mechanism. The first three hydrophobic residues of β2 are crucial for occlusion, while the remainder of the N-terminus remains flexible. Neither the closed channel conformation obtained in the absence of Ca nor an intermediate conformation found in the presence of Ca show density for the N-terminus of the β2 subunit in their pore, likely due to narrower side access portals preventing their entry into the channel pore.
External links	Nat Commun / PubMed:39971906 / PubMed Central
Methods	EM (single particle)
Resolution	2.57 - 3.54 Å
Structure data	46416 9czh EMDB-46416, PDB-9czh: Ca2+ bound intermediate state of hSlo1 + beta2N-beta4 channel in detergent. Method: EM (single particle) / Resolution: 2.9 Å 46418 9czj EMDB-46418, PDB-9czj: Ca2+ free hSlo1 + beta2N-beta4 channel in detergent. Method: EM (single particle) / Resolution: 3.54 Å 46419 9czk EMDB-46419, PDB-9czk: Ca2+ free hSlo1 + beta2N-beta4 channel in nanodisc. Method: EM (single particle) / Resolution: 3.5 Å 46421 9czm EMDB-46421, PDB-9czm: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in nanodisc. Method: EM (single particle) / Resolution: 2.57 Å 46423 9czo EMDB-46423, PDB-9czo: Ca2+ bound intermediate state of hSlo1 + beta2N-beta4 channel in nanodisc. Method: EM (single particle) / Resolution: 2.87 Å 46425 9czq 9d18 9d19 EMDB-46425, PDB-9czq: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent. PDB-9d18: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent-conformation 2 of inactivating domain PDB-9d19: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent-conformation 3 of inactivating domain Method: EM (single particle) / Resolution: 2.88 Å EMDB-46467: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent- Class 2 Method: EM (single particle) / Resolution: 2.96 Å EMDB-46468: Ca2+ bound open-inactivated hSlo1 + beta2N-beta4 channel in detergent-Class 3 Method: EM (single particle) / Resolution: 3.07 Å
Chemicals	ChemComp-CA: Unknown entry ChemComp-K: Unknown entry ChemComp-POV: (2S)-3-(hexadecanoyloxy)-2-[(9Z)-octadec-9-enoyloxy]propyl 2-(trimethylammonio)ethyl phosphate / phospholipidYM ChemComp-CLR: CHOLESTEROL ChemComp-MG*: Unknown entry
Source	homo sapiens (human)
Keywords	MEMBRANE PROTEIN / Potassium ion channel / calcium and voltage gated ion channel / big potassium channel / human BK / hSlo1 / intermediate hSlo1 / ball and chain inactivation / hSlo1 inactivating subunit complex / detergent micelle. / beta2 / beta4 subunits / apo hSlo1 / closed hSlo1 / detergent micelle / nanodisc / open-inactivated hSlo1 / beta2 beta4 / beta4