Related Experiment Video
Updated: Apr 17, 2026

Spot Variation Fluorescence Correlation Spectroscopy for Analysis of Molecular Diffusion at the Plasma Membrane of Living Cells
Published on: November 12, 2020
Barriers to the free diffusion of proteins and lipids in the plasma membrane
William S Trimble1, Sergio Grinstein2
1Cell Biology Program, Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, Canada.
Abstract:
Biological membranes segregate into specialized functional domains of distinct composition, which can persist for the entire life of the cell. How separation of their lipid and (glyco)protein components is generated and maintained is not well understood, but the existence of diffusional barriers has been proposed. Remarkably, the physical nature of such barriers and the manner whereby they impede the free diffusion of molecules in the plane of the membrane has rarely been studied in depth. Moreover, alternative mechanisms capable of generating membrane inhomogeneity are often disregarded. Here we describe prototypical biological systems where membrane segregation has been amply documented and discuss the role of diffusional barriers and other processes in the generation and maintenance of their structural and functional compartmentalization.
More Related Videos
Related Concept Videos
Protein Diffusion in the Membrane
Diffusion
Diffusion
Facilitated Transport
Facilitated Transport
Physiological Barriers
The blood endothelial barrier is the most porous of these. It allows all small ionized, un-ionized, and lipophilic molecules to pass through the endothelial lining into the interstitial space...

