High-resolution MAS NMR analysis of PI3-SH3 amyloid fibrils: backbone conformation and implications for protofilament assembly and structure .
High-resolution MAS NMR analysis of PI3-SH3 amyloid fibrils: backbone conformation and implications for protofilament assembly and structure .
复制标题
DOI：
10.1021/bi100864t
复制
发表时间：
2010-09-07
期刊：
影响因子：
2.9
通讯作者：
Griffin, Robert G.
中科院分区：
文献类型：
--
作者：
Bayro, Marvin J.;Maly, Thorsten;Birkett, Neil R.;MacPhee, Cait E.;Dobson, Christopher M.;Griffin, Robert G.
PI 3激酶的SH 3结构域（PI 3-SH 3或PI 3 K-SH 3）在体外容易聚集成纤维，并且已经用作研究淀粉样纤维的分子特性和形成机制的重要模型系统。我们描述的分子构象的PI 3-SH 3淀粉样纤维的形式所揭示的魔角旋转（MAS）固态核磁共振（NMR）光谱。这些原纤维的MAS NMR光谱显示出优异的分辨率，具有窄的13 C和15 N线宽，代表了高度的结构有序性和大部分多肽链不存在广泛的分子运动。我们已经确定了82的86个残基的蛋白质中的自旋系统，并获得了顺序共振分配其中的75个。化学位移分析表明，组成原纤维的蛋白质亚基采用紧凑的构象，由四个明确的β-折叠区和四个随机卷曲元件组成，具有不同程度的局部动力学或无序。原纤维形式的PI 3-SH 3的骨架构象与蛋白质的天然状态的骨架构象在二级结构和动态或无序片段的位置上都显著不同。我们在这里报告的PI 3-SH 3原纤维的位点特异性MAS NMR分析与以前发表的机理和结构数据进行了比较，从而详细解释了PI 3-SH 3介导原纤维形成的因素，并使我们能够提出一个可能的模型的核心结构的原纤维。我们的研究结果证实了PI 3-SH 3纤维和淀粉样蛋白之间的结构相似性直接相关的退行性或感染性疾病。
The SH3 domain of the PI3 kinase (PI3-SH3 or PI3K-SH3) readily aggregates into fibrils in vitro and has served as an important model system to investigate the molecular properties and mechanism of formation of amyloid fibrils. We describe the molecular conformation of PI3-SH3 in amyloid fibril form as revealed by magic-angle spinning (MAS) solid-state nuclear magnetic resonance (NMR) spectroscopy. The MAS NMR spectra of these fibrils display excellent resolution, with narrow 13C and 15N line widths, representing a high degree of structural order and the absence of extensive molecular motion for the majority of the polypeptide chain. We have identified the spin-systems of 82 of the 86 residues in the protein, and obtained sequential resonance assignments for 75 of them. Chemical shift analysis indicates that the protein subunits making up the fibril adopt a compact conformation consisting of four well-defined β-sheet regions and four random-coil elements with varying degrees of local dynamics or disorder. The backbone conformation of PI3-SH3 in fibril form differs significantly from that of the native state of the protein, both in secondary structure and in the location of dynamic or disordered segments. The site-specific MAS NMR analysis of PI3-SH3 fibrils we report here is compared with previously published mechanistic and structural data, resulting in a detailed interpretation of the factors that mediate fibril formation by PI3-SH3 and allowing us to propose a possible model of the core structure of the fibrils. Our results confirm the structural similarities between PI3-SH3 fibrils and amyloids directly related to degenerative or infectious diseases.
登录
查看更多内容
影响因子：
5.6
作者：
de Laureto, PP;Taddei, N;Fontana, A
通讯作者：
Fontana, A
DOI：
10.1073/pnas.0812227106
发表时间：
2009-05-12
影响因子：
11.1
作者：
Carullaa, Natalia;Zhou, Min;Dobson, Christopher M.
通讯作者：
Dobson, Christopher M.
影响因子：
4.4
作者：
BENNETT, AE;RIENSTRA, CM;GRIFFIN, RG
通讯作者：
GRIFFIN, RG
影响因子：
1.7
作者：
Baldus, M;Petkova, AT;Griffin, RG
通讯作者：
Griffin, RG
影响因子：
8
作者：
Ahn, Hee-Chul;Le, Yen T. H.;Lim, Kwang Hun
通讯作者：
Lim, Kwang Hun