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Atomic force microscopy study of early morphological changes during apoptosis.

Jessica A Hessler·Andrew Budor·Krishna Putchakayala·Almut Mecke·Daniel Rieger·Mark M Banaszak Holl·Bradford G Orr·Anna Bielinska·James Beals·James Baker
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Abstract

Apoptosis is defined by a distinct set of morphological changes observed during cell death including loss of focal adhesions, the formation of cell membrane buds or blebs, and a decrease in total cell volume. Recent studies suggest that these dramatic morphological changes, particularly apoptotic volume decrease (AVD), are an early prerequisite to apoptosis and precede key biochemical time-points. Here we use atomic force microscopy to observe early stage AVD of KB cells undergoing staurosporine-induced apoptosis. After a 3-h exposure to 1 microM staurosporine, a 32% decrease in total cell height and a 50% loss of total cell volume is observed accompanied by only a 15% change in cell diameter. The observed AVD precedes key biochemical hallmarks of apoptosis such as loss of mitochondrial membrane potential, phosphatidyl serine translocation, nuclear fragmentation, and measurable caspase-3 activity. This suggests that morphological volume changes occur very early in the induction of apoptosis.

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ApoptosisCell MembraneCell NucleusCell SizeHumansKB CellsMicroscopy, Atomic ForceMitochondriaPhosphatidylserinesTime FactorsJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, P.H.S.

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Jessica A Hessler, Andrew Budor, Krishna Putchakayala, Almut Mecke, Daniel Rieger, Mark M Banaszak Holl, Bradford G Orr, Anna Bielinska, James Beals, James Baker. 2005-09-27. Atomic force microscopy study of early morphological changes during apoptosis.. https://doi.org/10.1021/la051837g

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