ジャーナル: Cell Res / 年: 2018 タイトル: Amyloid fibril structure of α-synuclein determined by cryo-electron microscopy. 著者: Yaowang Li / Chunyu Zhao / Feng Luo / Zhenying Liu / Xinrui Gui / Zhipu Luo / Xiang Zhang / Dan Li / Cong Liu / Xueming Li / 要旨: α-Synuclein (α-syn) amyloid fibrils are the major component of Lewy bodies, which are the pathological hallmark of Parkinson's disease (PD) and other synucleinopathies. High-resolution structure of ...α-Synuclein (α-syn) amyloid fibrils are the major component of Lewy bodies, which are the pathological hallmark of Parkinson's disease (PD) and other synucleinopathies. High-resolution structure of α-syn fibril is important for understanding its assembly and pathological mechanism. Here, we determined a fibril structure of full-length α-syn (1-140) at the resolution of 3.07 Å by cryo-electron microscopy (cryo-EM). The fibrils are cytotoxic, and transmissible to induce endogenous α-syn aggregation in primary neurons. Based on the reconstructed cryo-EM density map, we were able to unambiguously build the fibril structure comprising residues 37-99. The α-syn amyloid fibril structure shows two protofilaments intertwining along an approximate 2 screw axis into a left-handed helix. Each protofilament features a Greek key-like topology. Remarkably, five out of the six early-onset PD familial mutations are located at the dimer interface of the fibril (H50Q, G51D, and A53T/E) or involved in the stabilization of the protofilament (E46K). Furthermore, these PD mutations lead to the formation of fibrils with polymorphic structures distinct from that of the wild-type. Our study provides molecular insight into the fibrillar assembly of α-syn at the atomic level and sheds light on the molecular pathogenesis caused by familial PD mutations of α-syn.
詳細: 4 microl of alpha-syn fibril solution was applied to a glow-discharged holey carbon grid (Quantifoil R1.2/1.3, 300 mesh), blotted for 6 s, and plunge-frozen in liquid ethane using FEI ...詳細: 4 microl of alpha-syn fibril solution was applied to a glow-discharged holey carbon grid (Quantifoil R1.2/1.3, 300 mesh), blotted for 6 s, and plunge-frozen in liquid ethane using FEI Vitrobot Mark IV. 95% humidity, 16 degrees グリッドの材料: COPPER / グリッドのサイズ: 300 divisions/in. / グリッドのタイプ: Quantifoil R1.2/1.3
急速凍結
装置: FEI VITROBOT MARK IV / 凍結剤: ETHANE / 湿度: 95 % / 凍結前の試料温度: 289 K