Department of Chemistry, University of Wisconsin-Madison, 1101 University Ave, Madison, WI 53706, USA.
Phys Chem Chem Phys. 2019 Jan 23;21(4):1863-1871. doi: 10.1039/c8cp06971a.
Intrinsically disordered proteins (IDPs) are crucial to many cellular processes and have been linked to neurodegenerative diseases. Single molecules of tau, an IDP associated with Alzheimer's disease, are trapped in solution using a microfluidic device, and a time-resolved fluorescence anisotropy decay is recorded for each molecule. Multiple rotational components are resolved and a novel k-means algorithm is used to sort the molecules into two families of conformations. Differences in rotational dynamics suggest a change in the rigidity and steric hindrance surrounding a sequence (306VQIVYK311) which is central to paired helical filament formation. This single-molecule approach can be applied to other IDPs to resolve heterogeneous populations and underlying differences in conformational dynamics.
无规卷曲蛋白 (IDP) 对许多细胞过程至关重要，并且与神经退行性疾病有关。使用微流控设备将与阿尔茨海默病相关的 IDP tau 的单个分子固定在溶液中，并记录每个分子的时间分辨荧光各向异性衰减。解析出多个旋转分量，并使用新的 K 均值算法将分子分为两种构象家族。旋转动力学的差异表明围绕一个序列 (306VQIVYK311) 的刚性和空间位阻发生变化，该序列是形成成对螺旋丝的关键。这种单分子方法可应用于其他 IDP 以解析异质群体和构象动力学的潜在差异。
