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Calcein Fluorescence Quenching to Measure Plasma Membrane Water Flux in Live Mammalian Cells.

ABSTRACT: Aquaporins (AQPs) are membrane channel proteins that facilitate the movement of water down osmotic gradients across biological membranes. This protocol allows measurements of AQP-mediated water transport across the plasma membrane of live mammalian cells. Calcein is a fluorescent dye that is quenched in a concentration-dependent manner. Therefore, on short timescales, its concentration-dependent fluorescence can be used as a probe of cell volume, and therefore a probe of water transport into or out of cells. For complete details on the use and execution of this protocol, please refer to Kitchen et al. (2020) and Kitchen and Conner (2015). For the underlying methodology development, please refer to Fenton et al. (2010) and Solenov et al. (2004).

SUBMITTER: Kitchen P

PROVIDER: S-EPMC7757292 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Calcein Fluorescence Quenching to Measure Plasma Membrane Water Flux in Live Mammalian Cells.

Kitchen Philip P Salman Mootaz M MM Abir-Awan Mohammed M Al-Jubair Tamim T Törnroth-Horsefield Susanna S Conner Alex C AC Bill Roslyn M RM

STAR protocols 20201102 3

Aquaporins (AQPs) are membrane channel proteins that facilitate the movement of water down osmotic gradients across biological membranes. This protocol allows measurements of AQP-mediated water transport across the plasma membrane of live mammalian cells. Calcein is a fluorescent dye that is quenched in a concentration-dependent manner. Therefore, on short timescales, its concentration-dependent fluorescence can be used as a probe of cell volume, and therefore a probe of water transport into or ...[more]

PMID: 33377051

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