MilliporeSigma

K+ Release Assay and K+ Measurement in Oocyte Assay.

Bio-protocol (2021-03-05)
Hong Li
ABSTRACT

The Xenopus oocyte is a powerful system for the exogenous expression and functional characterization of plant membrane transport proteins. Until now, a number of potassium transporters and channels have been identified in oocytes expression system by the two-electrode voltage clamp technology. It is difficult to characterize K+/H+ anti-transporters, especially, electroneutral transporter. The K+ efflux assay system enables easy, fast, large-scale measurement of the transporters activity without two-electrode voltage clamp technology. This protocol describes a technique to measure the efflux activity of potassium transporter in oocytes expressing system.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Potassium chloride, ACS reagent, 99.0-100.5%
Sigma-Aldrich
Sodium acetate, anhydrous, for molecular biology, ≥99%
Sigma-Aldrich
Sodium chloride, BioXtra, ≥99.5% (AT)
Sigma-Aldrich
Sodium bicarbonate, powder, BioReagent, for molecular biology, suitable for cell culture, suitable for insect cell culture
Sigma-Aldrich
Trypsin inhibitor from chicken egg white, Type III-O (free of ovoinhibitor)
Sigma-Aldrich
Collagenase from Clostridium histolyticum, for general use, Type I, 0.25-1.0 FALGPA units/mg solid, ≥125 CDU/mg solid
Sigma-Aldrich
Calcium chloride, anhydrous, granular, ≤7.0 mm, ≥93.0%
Sigma-Aldrich
MES, low moisture content, ≥99% (titration)
Sigma-Aldrich
Gentamicin sulfate, meets USP testing specifications, powder
Sigma-Aldrich
Proteinase K from Tritirachium album, lyophilized powder, BioUltra, ≥30 units/mg protein, for molecular biology
Sigma-Aldrich
Streptomycin Sulfate, Streptomyces sp. - CAS 3810-74-0 - Calbiochem, Streptomycin Sulfate, Streptomyces sp., CAS 3810-74-0, is an antibiotic effective against Gram-positive and Gram-negative bacteria. Blocks initiation, elongation, and termination in prokaryotes.
Sigma-Aldrich
Magnesium chloride hexahydrate, BioXtra, ≥99.0%