Endowed Scholars Program in Medical Science of UT southwestern medical center
米国
引用
ジャーナル: Nature / 年: 2017 タイトル: Human TRPML1 channel structures in open and closed conformations. 著者: Philip Schmiege / Michael Fine / Günter Blobel / Xiaochun Li / 要旨: Transient receptor potential mucolipin 1 (TRPML1) is a Ca-releasing cation channel that mediates the calcium signalling and homeostasis of lysosomes. Mutations in TRPML1 lead to mucolipidosis type ...Transient receptor potential mucolipin 1 (TRPML1) is a Ca-releasing cation channel that mediates the calcium signalling and homeostasis of lysosomes. Mutations in TRPML1 lead to mucolipidosis type IV, a severe lysosomal storage disorder. Here we report two electron cryo-microscopy structures of full-length human TRPML1: a 3.72-Å apo structure at pH 7.0 in the closed state, and a 3.49-Å agonist-bound structure at pH 6.0 in an open state. Several aromatic and hydrophobic residues in pore helix 1, helices S5 and S6, and helix S6 of a neighbouring subunit, form a hydrophobic cavity to house the agonist, suggesting a distinct agonist-binding site from that found in TRPV1, a TRP channel from a different subfamily. The opening of TRPML1 is associated with distinct dilations of its lower gate together with a slight structural movement of pore helix 1. Our work reveals the regulatory mechanism of TRPML channels, facilitates better understanding of TRP channel activation, and provides insights into the molecular basis of mucolipidosis type IV pathogenesis.
電子線照射量: 1.6 e/Å2 フィルム・検出器のモデル: GATAN K2 SUMMIT (4k x 4k)
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解析
ソフトウェア
名称: REFMAC / バージョン: 5.8.0158 / 分類: 精密化
EMソフトウェア
ID
名称
カテゴリ
1
RELION
粒子像選択
4
CTFFIND4
CTF補正
13
FREALIGN
3次元再構成
CTF補正
タイプ: PHASE FLIPPING AND AMPLITUDE CORRECTION
対称性
点対称性: C4 (4回回転対称)
3次元再構成
解像度: 3.72 Å / 解像度の算出法: FSC 0.143 CUT-OFF / 粒子像の数: 56105 / 対称性のタイプ: POINT
精密化
解像度: 3.7→78.69 Å / Cor.coef. Fo:Fc: 0.956 / SU B: 50.279 / SU ML: 0.668 立体化学のターゲット値: MAXIMUM LIKELIHOOD WITH PHASES 詳細: HYDROGENS HAVE BEEN ADDED IN THE RIDING POSITIONS
Rfactor
反射数
%反射
Rwork
0.30408
-
-
obs
0.30408
55348
99.99 %
溶媒の処理
イオンプローブ半径: 0.8 Å / 減衰半径: 0.8 Å / VDWプローブ半径: 1.2 Å / 溶媒モデル: MASK