ジャーナル: Structure / 年: 2020 タイトル: Near-Complete Structure and Model of Tel1ATM from Chaetomium thermophilum Reveals a Robust Autoinhibited ATP State. 著者: Marijke Jansma / Christian Linke-Winnebeck / Sebastian Eustermann / Katja Lammens / Dirk Kostrewa / Kristina Stakyte / Claudia Litz / Brigitte Kessler / Karl-Peter Hopfner / 要旨: Tel1 (ATM in humans) is a large kinase that resides in the cell in an autoinhibited dimeric state and upon activation orchestrates the cellular response to DNA damage. We report the structure of an ...Tel1 (ATM in humans) is a large kinase that resides in the cell in an autoinhibited dimeric state and upon activation orchestrates the cellular response to DNA damage. We report the structure of an endogenous Tel1 dimer from Chaetomium thermophilum. Major parts are at 2.8 Å resolution, including the kinase active site with ATPγS bound, and two different N-terminal solenoid conformations are at 3.4 Å and 3.6 Å, providing a side-chain model for 90% of the Tel1 polypeptide. We show that the N-terminal solenoid has DNA binding activity, but that its movements are not coupled to kinase activation. Although ATPγS and catalytic residues are poised for catalysis, the kinase resides in an autoinhibited state. The PIKK regulatory domain acts as a pseudo-substrate, blocking direct access to the site of catalysis. The structure allows mapping of human cancer mutations and defines mechanisms of autoinhibition at near-atomic resolution.
詳細: 1 mM MgCl2 and 0.1 mM ATPgS (final concentrations) added before plunging
凍結
凍結剤: ETHANE / チャンバー内湿度: 95 % / チャンバー内温度: 288.15 K / 装置: LEICA EM GP 詳細: TWEEN-20 was added to a final concentration of 0.05% immediately before vitrification. Sample was preincubated 45 seconds before plunging into liquid ethane..