Cholesterol depletion inhibits Na⁺,K⁺-ATPase activity in a near-native membrane environment.

ABSTRACT: Cholesterol's effects on Na⁺,K⁺-ATPase reconstituted in phospholipid vesicles have been extensively studied. However, previous studies have reported both cholesterol-mediated stimulation and inhibition of Na⁺,K⁺-ATPase activity. Here, using partial reaction kinetics determined via stopped-flow experiments, we studied cholesterol's effect on Na⁺,K⁺-ATPase in a near-native environment in which purified membrane fragments were depleted of cholesterol with methyl-β-cyclodextrin (mβCD). The mβCD-treated Na⁺,K⁺-ATPase had significantly reduced overall activity and exhibited decreased observed rate constants for ATP phosphorylation (ENa₃⁺ → E2P, i.e. phosphorylation by ATP and Na

SUBMITTER: Garcia A 

PROVIDER: S-EPMC6463725 | biostudies-literature | 2019 Apr

REPOSITORIES: biostudies-literature