脂質門控單價離子流調控內吞運輸並促進免疫監視
作者:
小柯機器人發布時間:2019/12/6 11:40:09
加拿大病童醫院Sergio Grinstein、Spencer A. Freeman等研究人員合作發現脂質門控單價離子流調控內吞運輸並促進免疫監視。相關論文2019年12月5日在線發表於國際學術期刊《科學》。
儘管胞外液(巨)胞飲作用的發生,但內吞途徑的體積保持不變。為了研究潛在的機制,研究人員使用高解析度的視頻成像技術來分析巨噬細胞在體外和原位形成的巨胞飲體的命運。
內化的主要陽離子滲透劑Na離子通過兩個孔道(TPC)離開胞吞液泡,同時伴隨Cl離子和滲透耦合水的平行流出。產生的收縮引起膜的起皺,促進了曲率敏感蛋白的募集。這些蛋白質穩定了管腔並促進了它們的伸長,促使液泡重塑、受體再循環和細胞器的分解。無法實現內吞的液體損害了駐留巨噬細胞的組織監測活性。因此,滲透驅動的內膜表面體積比增加促進了隔室之間的運輸並有助於確保組織的動態平衡。
附:英文原文
Title: Lipid-gated monovalent ion fluxes regulate endocytic traffic and support immune surveillance
Author: Spencer A. Freeman, Stefan Uderhardt, Amra Saric, Richard F. Collins, Catherine M. Buckley, Sivakami Mylvaganam, Parastoo Boroumand, Jonathan Plumb, Ronald N. Germain, Dejian Ren, Sergio Grinstein
Issue&Volume: 2019/12/05
Abstract: Despite ongoing (macro)pinocytosis of extracellular fluid, the volume of the endocytic pathway remains unchanged. To investigate the underlying mechanism, we used high-resolution video imaging to analyze the fate of macropinosomes formed by macrophages in vitro and in situ. Na+, the primary cationic osmolyte internalized, exited endocytic vacuoles via two pore channels (TPC), accompanied by parallel efflux of Cl and osmotically-coupled water. The resulting shrinkage caused crenation of the membrane which fostered recruitment of curvature-sensing proteins. These proteins stabilized tubules and promoted their elongation, driving vacuolar remodeling, receptor recycling, and resolution of the organelles. Failure to resolve internalized fluid impairs the tissue surveillance activity of resident macrophages. Thus, osmotically-driven increases in the surface-to-volume ratio of endomembranes promote traffic between compartments and help to ensure tissue homeostasis.
DOI: 10.1126/science.aaw9544
Source: https://science.sciencemag.org/content/early/2019/12/04/science.aaw9544
Science:《科學》,創刊於1880年。隸屬於美國科學促進會,最新IF:41.037