ジャーナル: Nature / 年: 2022 タイトル: Structural architecture of the human NALCN channelosome. 著者: Marc Kschonsak / Han Chow Chua / Claudia Weidling / Nourdine Chakouri / Cameron L Noland / Katharina Schott / Timothy Chang / Christine Tam / Nidhi Patel / Christopher P Arthur / Alexander ...著者: Marc Kschonsak / Han Chow Chua / Claudia Weidling / Nourdine Chakouri / Cameron L Noland / Katharina Schott / Timothy Chang / Christine Tam / Nidhi Patel / Christopher P Arthur / Alexander Leitner / Manu Ben-Johny / Claudio Ciferri / Stephan Alexander Pless / Jian Payandeh / 要旨: Depolarizing sodium (Na) leak currents carried by the NALCN channel regulate the resting membrane potential of many neurons to modulate respiration, circadian rhythm, locomotion and pain sensitivity. ...Depolarizing sodium (Na) leak currents carried by the NALCN channel regulate the resting membrane potential of many neurons to modulate respiration, circadian rhythm, locomotion and pain sensitivity. NALCN requires FAM155A, UNC79 and UNC80 to function, but the role of these auxiliary subunits is not understood. NALCN, UNC79 and UNC80 are essential in rodents, and mutations in human NALCN and UNC80 cause severe developmental and neurological disease. Here we determined the structure of the NALCN channelosome, an approximately 1-MDa complex, as fundamental aspects about the composition, assembly and gating of this channelosome remain obscure. UNC79 and UNC80 are massive HEAT-repeat proteins that form an intertwined anti-parallel superhelical assembly, which docks intracellularly onto the NALCN-FAM155A pore-forming subcomplex. Calmodulin copurifies bound to the carboxy-terminal domain of NALCN, identifying this region as a putative modulatory hub. Single-channel analyses uncovered a low open probability for the wild-type complex, highlighting the tightly closed S6 gate in the structure, and providing a basis to interpret the altered gating properties of disease-causing variants. Key constraints between the UNC79-UNC80 subcomplex and the NALCN DI-DII and DII-DIII linkers were identified, leading to a model of channelosome gating. Our results provide a structural blueprint to understand the physiology of the NALCN channelosome and a template for drug discovery to modulate the resting membrane potential.
超分子 #1: Pentameric complex of the leak channel NALCN with FAM155A, Calmod...
超分子
名称: Pentameric complex of the leak channel NALCN with FAM155A, Calmodulin, UNC79 and UNC80 タイプ: complex / ID: 1 / 親要素: 0 / 含まれる分子: #1-#5 詳細: Calmodulin was not overexpressed but co-purified from Expi293 cells
由来(天然)
生物種: Homo sapiens (ヒト)
+
分子 #1: Sodium leak channel non-selective protein,Enhanced green fluoresc...
分子
名称: Sodium leak channel non-selective protein,Enhanced green fluorescent protein タイプ: protein_or_peptide / ID: 1 / コピー数: 1 / 光学異性体: LEVO
凍結剤: ETHANE / チャンバー内湿度: 100 % / チャンバー内温度: 277 K / 装置: LEICA EM GP / 詳細: 3.5 sec blotting.
詳細
NALCN was reconstituted into lipid nanodiscs and mildly crosslinkned with 0.05% EM grade glutaraldehyde for 10 min at room temperature. Cross-linking was quenched with 9 mM Tris pH 7.5