Conformational Tuning of Amylin by Charged Styrene-Maleic-Acid Copolymers.
Conformational Tuning of Amylin by Charged Styrene-Maleic-Acid Copolymers.
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DOI：
10.1016/j.jmb.2021.167385
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发表时间：
2022-01-30
影响因子：
5.6
通讯作者：
Ramamoorthy A
中科院分区：
文献类型：
--
作者：
Sahoo BR;Souders CL 2nd;Watanabe-Nakayama T;Deng Z;Linton H;Suladze S;Ivanova MI;Reif B;Ando T;Martyniuk CJ;Ramamoorthy A
人类胰淀素形成结构不均的淀粉样蛋白，与2型糖尿病有关。因此，了解控制胰淀素聚集的分子相互作用可以为其致病形成提供机制上的见解。在这里，我们证明了人工合成的苯乙烯-马来酸两亲共聚物衍生物(SMAQA和SMAEA)改变了淀粉素的纤维形成。通过观察带正电的SMAQA快速形成球状低聚物和阻止纤颤，高速AFM被用来跟踪淀粉素的实时聚集。我们还观察到，在带负电荷的SMAEA存在的情况下，纤维形成加速。荧光、SOFAST-HMQC、DOSY和STD核磁共振实验进一步验证了这些发现。CD和FT-IR的构象分析表明，SMA共聚物对淀粉聚集体的构象有调节作用。SMAQA形成的物种为α螺旋结构，而SMAEA形成的物种具有丰富的β-Sheet结构。用核磁共振和微秒全原子分子动力学模拟绘制了SMAEA或SMAQA与胰淀素的相互作用界面。SMAEA与Phe23有π-π相互作用，与His18有静电π-阳离子相互作用，与Ala13和Val17有疏水堆积，而SMAQA与淀粉蛋白C末端(残基31-37)存在选择性相互作用，属于参与淀粉原纤化的两个β-Sheet区域之一(残基14-19和31-36)。毒性分析表明，两种SMA共聚物在体外都是无毒的，与共聚物形成的淀粉素物种对斑马鱼胚胎的畸形程度最小。总而言之，这项研究表明，化学工具，如共聚物，可以用来调节淀粉酶的聚集，改变物种的构象。
Human amylin forms structurally heterogeneous amyloids that have been linked to type-2 diabetes. Thus, understanding the molecular interactions governing amylin aggregation can provide mechanistic insights in its pathogenic formation. Here, we demonstrate that fibril formation of amylin is altered by synthetic amphipathic copolymer derivatives of the styrene-maleic-acid (SMAQA and SMAEA). High-speed AFM is used to follow the real-time aggregation of amylin by observing the rapid formation of de novo globular oligomers and arrestment of fibrillation by the positively-charged SMAQA. We also observed an accelerated fibril formation in the presence of the negatively-charged SMAEA. These findings were further validated by fluorescence, SOFAST-HMQC, DOSY and STD NMR experiments. Conformational analysis by CD and FT-IR revealed that the SMA copolymers modulate the conformation of amylin aggregates. While the species formed with SMAQA are α-helical, the ones formed with SMAEA are rich in β-sheet structure. The interacting interfaces between SMAEA or SMAQA and amylin are mapped by NMR and microseconds all-atom MD simulation. SMAEA displayed π-π interaction with Phe23, electrostatic π-cation interaction with His18 and hydrophobic packing with Ala13 and Val17; whereas SMAQA showed a selective interaction with amylin’s C-terminus (residues 31–37) that belongs to one of the two β-sheet regions (residues 14–19 and 31–36) involved in amylin fibrillation. Toxicity analysis showed both SMA copolymers to be non-toxic in vitro and the amylin species formed with the copolymers showed minimal deformity to zebrafish embryos. Together, this study demonstrates that chemical tools, such as copolymers, can be used to modulate amylin aggregation, alter the conformation of species.
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影响因子：
6.8
作者：
Huang J;MacKerell AD Jr
通讯作者：
MacKerell AD Jr
DOI：
10.1002/smll.201802825
发表时间：
2018-11
期刊：
Small (Weinheim an der Bergstrasse, Germany)
影响因子：
--
作者：
Faridi A;Sun Y;Okazaki Y;Peng G;Gao J;Kakinen A;Faridi P;Zhao M;Javed I;Purcell AW;Davis TP;Lin S;Oda R;Ding F;Ke PC
通讯作者：
Ke PC
影响因子：
5.1
作者：
HANABUSA, T;KUBO, K;NANJO, K
通讯作者：
NANJO, K
影响因子：
6
作者：
Gurlo, Tatyana;Ryazantsev, Sergey;Butler, Peter C.
通讯作者：
Butler, Peter C.
影响因子：
7.7
作者：
Lin, Chia-Yu;Gurlo, Tatyana;Butler, Peter C.
通讯作者：
Butler, Peter C.