Identification of caveolae-like structures on the surface of intact cells using scanning force microscopy

Item Type:	Article
Title:	Identification of caveolae-like structures on the surface of intact cells using scanning force microscopy
Creators Name:	Lucius, H. and Friedrichson, T. and Kurzchalia, T.V. and Lewin, G.R.
Abstract:	Caveolae are small, functionally important membrane invaginations found on the surface of many different cell types. Using electron microscopy, caveolae can be unequivocally identified in cell membranes by virtue of their size and the presence of caveolin/VIP22 proteins in the caveolar coat. In this study we have applied for the first time scanning force microscopy (SFM), to visualize caveolae on the surface of living and fixed cells. By scanning the membranes of Chinese hamster ovary cells (CHO), using the tapping mode of the SFM in fluid, we could visualize small membrane pits on the cell membranes of living and fixed cells. Two populations of pits with mean diameters of around 100 nm and 200 nm were present. In addition, the location of many pits visualized with the SFM was coincident with membrane spots fluorescently labeled with a green fluorescent protein-caveolin-1 fusion protein. Scanning force microscopy on cells treated with methyl-β-cyclodextrin, an agent that sequesters cholesterol and disrupts caveolae, abolished pits with a measured diameter of 100 nm but left pits of around 200 nm diameter intact. Thus, the smallest membrane pits measured with the SFM in CHO cells were indeed very likely to be identical to caveolae. These experiments show for the first time that SFM can be used to visualize caveolae in intact cells.
Keywords:	Atomic Force Microscopy, Caveolae, GFP, Membrane Pits, Methyl-{beta}-Cyclodextrin, Caveolin-1, Cholesterol, Coated Vesicles, CHO cells, Animals
Source:	Journal of Membrane Biology
ISSN:	0022-2631
Publisher:	Springer
Volume:	194
Number:	2
Page Range:	97-108
Date:	June 2003
Official Publication:	https://doi.org/10.1007/s00232-003-2029-5
PubMed:	View item in PubMed

Repository Staff Only: item control page