Revealing the aggregation and fibrillation process of variant amyloid proteins is critical for understanding the molecular mechanism of related amyloidosis diseases. Here we characterized the fibrillation morphology and kinetics of type 2 diabetes (T2D) related human islet amyloid polypeptide (hIAPP_1-37) fibril formation process using negative staining transmission electron microscopy (NS-TEM), cryo-electron microscopy (cryo-EM) analysis, and 3D cryo-electron tomography (cryo-ET) reconstruction, together with circular dichroism (CD) and Thioflavin-T (ThT) assays. Our results showed that various amyloid fibrils can be observed at different time points of hIAPP₁₋₃₇ fibrillization process, while the winding of protofibrils presents in different growth stages, which suggests a synchronous process of hIAPP_1-37 amyloid fibrillization. This work provides insights into the understanding of hIAPP_1-37 amyloid aggregation process and the pathogenesis of Type 2 diabetes disease.

揭示变体淀粉样蛋白的聚集和原纤维化过程对于理解相关淀粉样变性病的分子机制至关重要。在这里，我们使用负染色透射电子显微镜（NS-TEM），冷冻电子显微镜（cryo-EM）对2型糖尿病（T2D）相关的人类胰岛淀粉样多肽（hIAPP _1-37）原纤维形成过程的原纤维形态和动力学进行了表征分析和3D冷冻电子断层扫描（cryo-ET）重建，以及圆二色性（CD）和硫黄素-T（ThT）分析。我们的结果表明，在hIAPP _1-37的不同时间点可以观察到各种淀粉样原纤维原纤维的缠绕存在于不同的生长阶段，这表明hIAPP _1-37淀粉样蛋白原纤维化是一个同步过程。这项工作提供了对hIAPP _1-37淀粉样蛋白聚集过程的理解和2型糖尿病疾病发病机理的见解。