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Quantifying hydrostatic pressure in plant cells by using indentation with an atomic force microscope.

ABSTRACT: Plant cell growth depends on a delicate balance between an inner drive-the hydrostatic pressure known as turgor-and an outer restraint-the polymeric wall that surrounds a cell. The classical technique to measure turgor in a single cell, the pressure probe, is intrusive and cannot be applied to small cells. In order to overcome these limitations, we developed a method that combines quantification of topography, nanoindentation force measurements, and an interpretation using a published mechanical model for the pointlike loading of thin elastic shells. We used atomic force microscopy to estimate the elastic properties of the cell wall and turgor pressure from a single force-depth curve. We applied this method to onion epidermal peels and quantified the response to changes in osmolality of the bathing solution. Overall our approach is accessible and enables a straightforward estimation of the hydrostatic pressure inside a walled cell.

SUBMITTER: Beauzamy L

PROVIDER: S-EPMC4457008 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Quantifying hydrostatic pressure in plant cells by using indentation with an atomic force microscope.

Beauzamy Léna L Derr Julien J Boudaoud Arezki A

Biophysical journal 20150501 10

Plant cell growth depends on a delicate balance between an inner drive-the hydrostatic pressure known as turgor-and an outer restraint-the polymeric wall that surrounds a cell. The classical technique to measure turgor in a single cell, the pressure probe, is intrusive and cannot be applied to small cells. In order to overcome these limitations, we developed a method that combines quantification of topography, nanoindentation force measurements, and an interpretation using a published mechanical ...[more]

PMID: 25992723

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