活細胞超分辨PAINT成像揭示皮牛級別細胞牽引力
作者:
小柯機器人發布時間:2020/9/17 16:00:43
埃默裡大學Khalid Salaita研究小組取得一項新突破。他們的研究開發出了活細胞超分辨PAINT技術用於成像皮牛(pN)級別細胞牽引力量。 這一研究成果發表在2020年9月14日出版的《自然—方法學》上。
該研究團隊通過整合分子張力探針和DNA點積累在納米尺度的地形(DNA-PAINT)成像技術開發了tPAINT,用於映射~25-nm解析度下皮牛級別機械力。為實現活細胞動態張力成像,課題組設計了可逆探針,該探針有一個神秘的對接位點,只有在探針受到作用力超過機械閾值(~ 7-21 pN)時才會出現。
此外,課題組報告了第二種不可逆tPAINT探針,其對接位點永久暴露,可以整合力隨時間的歷史變化,從而提供通過時間動力學信息換取更高空間解析度的可能。研究團隊應用這兩種類型的tPAINT探針,在活的人類血小板和老鼠胚胎成纖維細胞中映射整合素受體所受機械力。重要的是,tPAINT揭示了細胞前沿的血小板受力與Arp2/3複合物核化的動態肌動蛋白環之間的關聯。
據介紹,儘管機械力在生物學中起著至關重要的作用,但在亞100 nm解析度尺度成像細胞力仍然是一個挑戰。
附:英文原文
Title: Live-cell super-resolved PAINT imaging of piconewton cellular traction forces
Author: Joshua M. Brockman, Hanquan Su, Aaron T. Blanchard, Yuxin Duan, Travis Meyer, M. Edward Quach, Roxanne Glazier, Alisina Bazrafshan, Rachel L. Bender, Anna V. Kellner, Hiroaki Ogasawara, Rong Ma, Florian Schueder, Brian G. Petrich, Ralf Jungmann, Renhao Li, Alexa L. Mattheyses, Yonggang Ke, Khalid Salaita
Issue&Volume: 2020-09-14
Abstract: Despite the vital role of mechanical forces in biology, it still remains a challenge to image cellular force with sub-100-nm resolution. Here, we present tension points accumulation for imaging in nanoscale topography (tPAINT), integrating molecular tension probes with the DNA points accumulation for imaging in nanoscale topography (DNA-PAINT) technique to map piconewton mechanical events with ~25-nm resolution. To perform live-cell dynamic tension imaging, we engineered reversible probes with a cryptic docking site revealed only when the probe experiences forces exceeding a defined mechanical threshold (~7–21pN). Additionally, we report a second type of irreversible tPAINT probe that exposes its cryptic docking site permanently and thus integrates force history over time, offering improved spatial resolution in exchange for temporal dynamics. We applied both types of tPAINT probes to map integrin receptor forces in live human platelets and mouse embryonic fibroblasts. Importantly, tPAINT revealed a link between platelet forces at the leading edge of cells and the dynamic actin-rich ring nucleated by the Arp2/3 complex.
DOI: 10.1038/s41592-020-0929-2
Source: https://www.nature.com/articles/s41592-020-0929-2