ジャーナル: Nat Commun / 年: 2019 タイトル: The structural basis of lipid scrambling and inactivation in the endoplasmic reticulum scramblase TMEM16K. 著者: Simon R Bushell / Ashley C W Pike / Maria E Falzone / Nils J G Rorsman / Chau M Ta / Robin A Corey / Thomas D Newport / John C Christianson / Lara F Scofano / Chitra A Shintre / Annamaria ...著者: Simon R Bushell / Ashley C W Pike / Maria E Falzone / Nils J G Rorsman / Chau M Ta / Robin A Corey / Thomas D Newport / John C Christianson / Lara F Scofano / Chitra A Shintre / Annamaria Tessitore / Amy Chu / Qinrui Wang / Leela Shrestha / Shubhashish M M Mukhopadhyay / James D Love / Nicola A Burgess-Brown / Rebecca Sitsapesan / Phillip J Stansfeld / Juha T Huiskonen / Paolo Tammaro / Alessio Accardi / Elisabeth P Carpenter / 要旨: Membranes in cells have defined distributions of lipids in each leaflet, controlled by lipid scramblases and flip/floppases. However, for some intracellular membranes such as the endoplasmic ...Membranes in cells have defined distributions of lipids in each leaflet, controlled by lipid scramblases and flip/floppases. However, for some intracellular membranes such as the endoplasmic reticulum (ER) the scramblases have not been identified. Members of the TMEM16 family have either lipid scramblase or chloride channel activity. Although TMEM16K is widely distributed and associated with the neurological disorder autosomal recessive spinocerebellar ataxia type 10 (SCAR10), its location in cells, function and structure are largely uncharacterised. Here we show that TMEM16K is an ER-resident lipid scramblase with a requirement for short chain lipids and calcium for robust activity. Crystal structures of TMEM16K show a scramblase fold, with an open lipid transporting groove. Additional cryo-EM structures reveal extensive conformational changes from the cytoplasmic to the ER side of the membrane, giving a state with a closed lipid permeation pathway. Molecular dynamics simulations showed that the open-groove conformation is necessary for scramblase activity.
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2019年3月26日
登録サイト: PDBE / 処理サイト: PDBE
改定 1.0
2019年5月1日
Provider: repository / タイプ: Initial release
改定 1.1
2019年7月10日
Group: Data collection / カテゴリ: diffrn_source / Item: _diffrn_source.pdbx_synchrotron_site
解像度: 3.5→39.69 Å / Cor.coef. Fo:Fc: 0.817 / Cor.coef. Fo:Fc free: 0.794 / 交差検証法: THROUGHOUT / σ(F): 0 / SU Rfree Blow DPI: 0.605 詳細: Structure refined using STARANISO anistropically truncated data. Reference model (LSSR) restraints to PDB:5OC9 were also used