Mutual dependence of Na,K-ATPase alpha- and beta-subunits for correct posttranslational processing and intracellular transport

Abstract

In this study, we have followed the fate of newly synthesized alpha- and beta-subunits of Na,K-ATPase in Xenopus oocytes injected with alpha and/or beta cRNA to examine whether assembly of the two subunits is needed for a correct folding and/or for intracellular transport of Na,K-ATPase. Our data indicate that (1) assembly of alpha- and beta-subunits occurs at the level of the ER, (2) beta-subunits are needed for the newly synthesized alpha-subunit to adopt a stable configuration and (3) alpha- and beta-subunits mutually depend on each other to be transported out of the ER.