Mutual dependence of Na,K-ATPase alpha- and beta-subunits for correct posttranslational processing and intracellular transport.
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.
Ackermann
U
U
Institut de Pharmacologie de l'Université, Lausanne, Switzerland.
Geering
K
K
D000818:Animals; D001692:Biological Transport; D002451:Cell Compartmentation; D004721:Endoplasmic Reticulum / Q000378:metabolism; D006031:Glycosylation; D066298:In Vitro Techniques; D046911:Macromolecular Substances; D008562:Membrane Glycoproteins / Q000378:metabolism* / Q000648:ultrastructure; D008657:Metabolic Clearance Rate; D008845:Microinjections; D011233:Precipitin Tests; D011487:Protein Conformation; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000235:genetics; D000254:Sodium-Potassium-Exchanging ATPase / Q000235:genetics / Q000378:metabolism*; D013997:Time Factors; D014982:Xenopus laevis
D046911:Macromolecular Substances; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D000254:Sodium-Potassium-Exchanging ATPase