凝聚蛋白質老化成麥克斯韋流體
作者:
小柯機器人發布時間:2020/12/14 16:05:57
德國馬克斯·普朗克研究所Frank Jülicher研究團隊發現凝聚蛋白質老化後呈現為麥克斯韋流體。 該項研究成果發表在2020年12月11日出版的《科學》。
凝聚蛋白質是一種複雜的流體,可以隨時間改變其物質的流變性。然而,這些流體合適的流變學描述仍然缺失。
該文中,研究人員使用基於雷射鑷子的主動流變學和基於微珠的被動流變學來表徵體外蛋白質聚合物的時間依賴特性。對於不同的蛋白質,凝聚蛋白質經不同老化時間均表現為粘彈性麥克斯韋流體。它們的粘度隨老化時間的增加而顯著增加,而彈性模量變化不大。在早期和晚期,電子顯微鏡下未發現明顯的結構差異。
因此得出結論,蛋白質凝聚物可以是軟玻璃狀材料,具有與老化時間相關的材料屬性,研究人員稱之為麥克斯韋玻璃。研究人員討論了玻璃化行為對細胞生物化學調節的可能優勢。
附:英文原文
Title: Protein condensates as aging Maxwell fluids
Author: Louise Jawerth, Elisabeth Fischer-Friedrich, Suropriya Saha, Jie Wang, Titus Franzmann, Xiaojie Zhang, Jenny Sachweh, Martine Ruer, Mahdiye Ijavi, Shambaditya Saha, Julia Mahamid, Anthony A. Hyman, Frank Jülicher
Issue&Volume: 2020/12/11
Abstract: Protein condensates are complex fluids that can change their material properties with time. However, an appropriate rheological description of these fluids remains missing. We characterize the time-dependent material properties of in vitro protein condensates using laser tweezer–based active and microbead-based passive rheology. For different proteins, the condensates behave at all ages as viscoelastic Maxwell fluids. Their viscosity strongly increases with age while their elastic modulus varies weakly. No significant differences in structure were seen by electron microscopy at early and late ages. We conclude that protein condensates can be soft glassy materials that we call Maxwell glasses with age-dependent material properties. We discuss possible advantages of glassy behavior for modulation of cellular biochemistry.
DOI: 10.1126/science.aaw4951
Source: https://science.sciencemag.org/content/370/6522/1317