Mechanistic insight into the relationship between N-terminal acetylation of α-synuclein and fibril formation rates by NMR and fluorescence.
Mechanistic insight into the relationship between N-terminal acetylation of α-synuclein and fibril formation rates by NMR and fluorescence.
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DOI：
10.1371/journal.pone.0075018
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发表时间：
2013
期刊：
影响因子：
3.7
通讯作者：
Baum J
中科院分区：
文献类型：
--
作者：
Kang L;Janowska MK;Moriarty GM;Baum J
α-突触核蛋白（αSyn）是帕金森病患者路易体内含物中的主要蛋白组分，当正常可溶的内在无序蛋白转化为淀粉样纤维时，α-突触核蛋白（αSyn）聚集。在这项工作中，我们提供了一个机制的观点，N-末端乙酰化的作用，首先建立单体二级结构倾向和原纤维组装动力学之间的定量关系，其次通过证明在N-末端乙酰化形式的早发性A53 T突变，N-末端瞬时螺旋形成和/或抑制N-末端乙酰化调节原纤维组装速率。使用NMR化学位移和荧光实验，我们报告了残基5-8，14-31和50-57中的二级结构倾向与原纤维生长速率高度相关。N-末端乙酰化A53 T和WT αSyn与非乙酰化A53 T和WT α Syn的二级结构倾向和纤维生长速率的四因素比较提供了N-末端乙酰化在淀粉样蛋白纤维形成中作用的新机制见解。我们表明，N-末端乙酰化抑制的“原纤化促进”瞬时螺旋的形成在残基14-31产生的A53 T突变的非乙酰化的变体，并支持形成的“原纤化抑制”瞬时螺旋的残基1-12，从而导致在较慢的原纤化率相对于先前研究的非乙酰化的A53 T的变体。我们的研究结果突出了关键的相互作用的区域特异性的瞬态二级结构的N-末端区域与原纤维，和N-末端乙酰基在原纤维形成的抑制作用。
Aggregation of α-synuclein (αSyn), the primary protein component in Lewy body inclusions of patients with Parkinson’s disease, arises when the normally soluble intrinsically disordered protein converts to amyloid fibrils. In this work, we provide a mechanistic view of the role of N-terminal acetylation on fibrillation by first establishing a quantitative relationship between monomer secondary structural propensity and fibril assembly kinetics, and secondly by demonstrating in the N-terminal acetylated form of the early onset A53T mutation, that N-terminal transient helices formed and/or inhibited by N-terminal acetylation modulate the fibril assembly rates. Using NMR chemical shifts and fluorescence experiments, we report that secondary structural propensity in residues 5–8, 14–31, and 50–57 are highly correlated to fibril growth rate. A four-way comparison of secondary structure propensity and fibril growth rates of N-terminally acetylated A53T and WT αSyn with non-acetylated A53T and WT αSyn present novel mechanistic insight into the role of N-terminal acetylation in amyloid fibril formation. We show that N-terminal acetylation inhibits the formation of the “fibrillation promoting” transient helix at residues 14–31 resulting from the A53T mutation in the non-acetylated variant and supports the formation of the “fibrillation inhibiting” transient helix in residues 1–12 thereby resulting in slower fibrillation rates relative to the previously studied non-acetylated A53T variant. Our results highlight the critical interplay of the region-specific transient secondary structure of the N-terminal region with fibrillation, and the inhibitory role of the N-terminal acetyl group in fibril formation.
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DOI：
10.1073/pnas.0407146102
发表时间：
2005-02-01
影响因子：
11.1
作者：
Bertoncini, CW;Jung, YS;Zweckstetter, M
通讯作者：
Zweckstetter, M
影响因子：
5.6
作者：
Ma B;Nussinov R
通讯作者：
Nussinov R
影响因子：
2.9
作者：
Kim, TD;Paik, SR;Yang, CH
通讯作者：
Yang, CH
影响因子：
13.8
作者：
Dobson, CM
通讯作者：
Dobson, CM
影响因子：
3.4
作者：
Brorsson, Ann-Christin;Bolognesi, Benedetta;Luheshi, Leila M.
通讯作者：
Luheshi, Leila M.