康奈尔大学Matthew J. Paszek研究组近期的工作阐述了糖萼调控细胞膜形貌的物理原理。该研究成果发表在2019年6月出版的国际学术期刊《细胞》上。

细胞能够将质膜弯折成高度弯曲的形貌来与外界局部环境接触，但这些形貌生成是如何被调控的还未彻底解析。

在这项工作中，研究人员报道了细胞形貌产生过程中，细胞内部的改变过程与细胞表明糖萼的组织之间的协同作用。糖萼中的黏蛋白生物高分子与长链多糖能够产生熵力，从而有利或不利于细胞表面挤压出球状和指头状的延伸。糖萼的高分子刷模型成功地预测了磷脂高分子的尺寸和细胞膜的密度对质膜形貌的影响。特定的糖萼组合能够导致质膜不稳定，从而产生凹凸不平的珍珠状膜结构，并促使外泌小泡的分泌。总而言之，这项工作表明，糖萼在调控细胞膜弯曲中扮演了一个基本的角色，并为细胞与细胞、细胞与胞外基质之间的交流提供可能。

附：英文摘要

Title: Physical Principles of Membrane Shape Regulation by the Glycocalyx

Author: Carolyn R. Shurer, Joe Chin-Hun Kuo, LaDeidra Monét Roberts, Gerald W. Feigenson, Heidi L. Reesink, Matthew J. Paszek

Issue&Volume: Jun 13, 2019 Volume 177Issue 7

Abstract: Cells bend their plasma membranes into highly curved forms to interact with the local environment, but how shape generation is regulated is not fully resolved. Here, we report a synergy between shape-generating processes in the cell interior and the external organization and composition of the cell-surface glycocalyx. Mucin biopolymers and long-chain polysaccharides within the glycocalyx can generate entropic forces that favor or disfavor the projection of spherical and finger-like extensions from the cell surface. A polymer brush model of the glycocalyx successfully predicts the effects of polymer size and cell-surface density on membrane morphologies. Specific glycocalyx compositions can also induce plasma membrane instabilities to generate more exotic undulating and pearled membrane structures and drive secretion of extracellular vesicles. Together, our results suggest a fundamental role for the glycocalyx in regulating curved membrane features that serve in communication between cells and with the extracellular matrix.

DOI: https://doi.org/10.1016/j.cell.2019.04.017

Source: https://www.cell.com/cell/fulltext/S0092-8674(19)30403-9