6V35

Cryo-EM structure of Ca2+-free hsSlo1-beta4 channel complex

6V35 の概要

• エントリーDOI: 10.2210/pdb6v35/pdb
• 関連するPDBエントリー: 6V22
• EMDBエントリー: 21025 21028 21029 21036
• 分子名称: Calcium-activated potassium channel subunit alpha-1, Calcium-activated potassium channel subunit beta-4, (1R)-2-{[(S)-{[(2S)-2,3-dihydroxypropyl]oxy}(hydroxy)phosphoryl]oxy}-1-[(hexadecanoyloxy)methyl]ethyl (9Z)-octadec-9-enoate, ... (5 entities in total)
• 機能のキーワード: high conductance ca2+-activated k+ channel, slo1 channel, bk channel, maxik channel, slo1 beta subunit, beta4 subunit, transport protein
• 由来する生物種: Homo sapiens (Human); 詳細
• タンパク質・核酸の鎖数: 8
• 化学式量合計: 614742.45

構造登録者

Tao, X.,MacKinnon, R. (登録日: 2019-11-25, 公開日: 2019-12-25, 最終更新日: 2024-10-30)

主引用文献

Tao, X.,MacKinnon, R.
Molecular structures of the human Slo1 K + channel in complex with beta 4.
Elife, 8:-, 2019

PubMed Abstract: Slo1 is a Ca- and voltage-activated K channel that underlies skeletal and smooth muscle contraction, audition, hormone secretion and neurotransmitter release. In mammals, Slo1 is regulated by auxiliary proteins that confer tissue-specific gating and pharmacological properties. This study presents cryo-EM structures of Slo1 in complex with the auxiliary protein, β4. Four β4, each containing two transmembrane helices, encircle Slo1, contacting it through helical interactions inside the membrane. On the extracellular side, β4 forms a tetrameric crown over the pore. Structures with high and low Ca concentrations show that identical gating conformations occur in the absence and presence of β4, implying that β4 serves to modulate the relative stabilities of 'pre-existing' conformations rather than creating new ones. The effects of β4 on scorpion toxin inhibition kinetics are explained by the crown, which constrains access but does not prevent binding.

PubMed: 31815672
DOI: 10.7554/eLife.51409

実験手法

ELECTRON MICROSCOPY (3.5 Å)