Regulation of Intracellular Cholesterol Distribution by Na/K-ATPase

Regulation of intracellular cholesterol distribution by Na/K-ATPase.

Recent studies have ascribed many non-pumping functions to the Na/K-ATPase. We show here that graded knockdown of cellular Na/K-ATPase alpha1 subunit produces a parallel decrease in both caveolin-1 and cholesterol in light fractions of LLC-PK1 cell lysates. This observation is further substantiated by imaging analyses, showing redistribution of cholesterol from the plasma membrane to intracellu...

Regulation of NaK-ATPase Activity by Neurotransmitters

The hitherto unknown NT-regulated mechanism of NaK-ATPase localized in the nerve ending membranes is found. The mechanism certainly has a functional significance and must be involved in the regulation – modulation of chemical synaptic transmission. On the other hand , the availability of the discovered specific protein, regulators (SFa and SFi) of synaptic origin, makes it possible to consider ...

Modeling Spatial Distribution of Intracellular Organelles by Molecular Motors

Localization of NaK ATPase on cultured human retinal pigment epithelium.

PURPOSE To localize NaK ATPase sites on cultured human retinal pigment epithelium (RPE). METHODS Cultured human RPE from fetal, 2-year-old, and 21-year-old donors was grown to confluence in microporous culture wells for 4 months to 2 years, mounted in a small-volume Ussing chamber, and perfused with growth medium. Ouabain (10(-5)-M) was applied to the basal and apical sides of the RPE. Change...

Role of adenosine triphosphate (ATP) and NaK ATPase in the inhibition of proximal tubule transport with intracellular cystine loading.

Cellular cystine loading with cystine dimethyl ester inhibits volume absorption, transepithelial potential difference, glucose transport, and bicarbonate transport in proximal convoluted tubules perfused in vitro. This study examined the roles of ATP and NaK ATPase in this in vitro model of the Fanconi syndrome of cystinosis. Intracellular ATP was measured using the luciferin-luciferase assay. ...