National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)
GM056324
米国
引用
ジャーナル: Structure / 年: 2019 タイトル: Structural Organization and Dynamics of Homodimeric Cytohesin Family Arf GTPase Exchange Factors in Solution and on Membranes. 著者: Sanchaita Das / Andrew W Malaby / Agata Nawrotek / Wenhua Zhang / Mahel Zeghouf / Sarah Maslen / Mark Skehel / Srinivas Chakravarthy / Thomas C Irving / Osman Bilsel / Jacqueline Cherfils / David G Lambright / 要旨: Membrane dynamic processes require Arf GTPase activation by guanine nucleotide exchange factors (GEFs) with a Sec7 domain. Cytohesin family Arf GEFs function in signaling and cell migration through ...Membrane dynamic processes require Arf GTPase activation by guanine nucleotide exchange factors (GEFs) with a Sec7 domain. Cytohesin family Arf GEFs function in signaling and cell migration through Arf GTPase activation on the plasma membrane and endosomes. In this study, the structural organization of two cytohesins (Grp1 and ARNO) was investigated in solution by size exclusion-small angle X-ray scattering and negative stain-electron microscopy and on membranes by dynamic light scattering, hydrogen-deuterium exchange-mass spectrometry and guanosine diphosphate (GDP)/guanosine triphosphate (GTP) exchange assays. The results suggest that cytohesins form elongated dimers with a central coiled coil and membrane-binding pleckstrin-homology (PH) domains at opposite ends. The dimers display significant conformational heterogeneity, with a preference for compact to intermediate conformations. Phosphoinositide-dependent membrane recruitment is mediated by one PH domain at a time and alters the conformational dynamics to prime allosteric activation by Arf-GTP. A structural model for membrane targeting and allosteric activation of full-length cytohesin dimers is discussed.
Chain - Chain ID: B / Chain - Residue range: 63-399 / Chain - Source name: PDB / Chain - Initial model type: experimental model
詳細
The model with the best correlation coefficient was selected by ADP_EM from a pool of 10000 models generated by RRT_SAMPLE using rigid bodies derived from 2R09 (autoinhibited core, amino acids 63-399) and a canonical antiparallel coiled coil (amino acids 18-53) built with CCBuilder. Flexible regions with reasonable geometry were modeled with MODELLER.
精密化
空間: REAL / プロトコル: RIGID BODY FIT / 当てはまり具合の基準: Correlation coefficient
得られたモデル
PDB-6u3g: Best fitting antiparallel model for Volume 2 of truncated dimeric Cytohesin-3 (Grp1; amino acids 14-399)