ジャーナル: Cell Rep / 年: 2014 タイトル: A dynamin mutant defines a superconstricted prefission state. 著者: Anna C Sundborger / Shunming Fang / Jürgen A Heymann / Pampa Ray / Joshua S Chappie / Jenny E Hinshaw / 要旨: Dynamin is a 100 kDa GTPase that organizes into helical assemblies at the base of nascent clathrin-coated vesicles. Formation of these oligomers stimulates the intrinsic GTPase activity of dynamin, ...Dynamin is a 100 kDa GTPase that organizes into helical assemblies at the base of nascent clathrin-coated vesicles. Formation of these oligomers stimulates the intrinsic GTPase activity of dynamin, which is necessary for efficient membrane fission during endocytosis. Recent evidence suggests that the transition state of dynamin's GTP hydrolysis reaction serves as a key determinant of productive fission. Here, we present the structure of a transition-state-defective dynamin mutant K44A trapped in a prefission state at 12.5 Å resolution. This structure constricts to 3.7 nm, reaching the theoretical limit required for spontaneous membrane fission. Computational docking indicates that the ground-state conformation of the dynamin polymer is sufficient to achieve this superconstricted prefission state and reveals how a two-start helical symmetry promotes the most efficient packing of dynamin tetramers around the membrane neck. These data suggest a model for the assembly and regulation of the minimal dynamin fission machine.
名称: GTP STABILIZED HUMAN DYNAMIN 1 K44A SUPER CONSTRICTED POLYMER タイプ: COMPLEX 詳細: K44A DYNAMIN HELICAL TUBES GENERATED IN THE PRESENCE OF GTP AND DOPS LIPOSOMES
緩衝液
pH: 7.2
試料
包埋: NO / シャドウイング: NO / 染色: NO / 凍結: YES
試料支持
詳細: HOLEY CARBON
急速凍結
装置: LEICA EM GP / 凍結剤: ETHANE / 詳細: PLUNGE FROZEN IN LIQUID ETHANE
モード: BRIGHT FIELD / 倍率(公称値): 49000 X / 最大 デフォーカス(公称値): 2500 nm / 最小 デフォーカス(公称値): 500 nm
撮影
電子線照射量: 10 e/Å2 / フィルム・検出器のモデル: KODAK SO-163 FILM
放射波長
相対比: 1
-
解析
EMソフトウェア
ID
名称
カテゴリ
1
Yup.scx
モデルフィッティング
2
SPIDER
3次元再構成
CTF補正
詳細: INDIVIDUAL IMAGES
3次元再構成
手法: IHRSR / 解像度: 12.5 Å / 粒子像の数: 7525 / ピクセルサイズ(公称値): 2.55 Å 詳細: THIS MODEL INCORPORATES COORDINATES FROM 3ZYC, , 3SNH, AND 1DYN, WHICH WERE DOCKED INTO A HELICAL CRYO-EM DENSITY. SUBMISSION BASED ON EXPERIMENTAL DATA FROM EMDB EMD-270. SUBMISSION BASED ON ...詳細: THIS MODEL INCORPORATES COORDINATES FROM 3ZYC, , 3SNH, AND 1DYN, WHICH WERE DOCKED INTO A HELICAL CRYO-EM DENSITY. SUBMISSION BASED ON EXPERIMENTAL DATA FROM EMDB EMD-270. SUBMISSION BASED ON EXPERIMENTAL DATA FROM EMDB EMD-2701. (DEPOSITION ID: 12555). 対称性のタイプ: HELICAL
原子モデル構築
プロトコル: FLEXIBLE FIT / 空間: REAL / 詳細: METHOD--YUP ALGORITHM REFINEMENT PROTOCOL--X-RAY