Mutation of a conserved proline residue in the beta-subunit ectodomain prevents Na(+)-K(+)-ATPase oligomerization
Details
Serval ID
serval:BIB_273B8B1EE078
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Mutation of a conserved proline residue in the beta-subunit ectodomain prevents Na(+)-K(+)-ATPase oligomerization
Journal
American Journal of Physiology
ISSN
0363-6143
Publication state
Published
Issued date
10/1993
Volume
265
Number
4 Pt 1
Pages
C1169-74
Notes
Journal Article
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S. --- Old month value: Oct
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, P.H.S. --- Old month value: Oct
Abstract
A highly conserved sequence motif (4 tyrosines and 1 proline: YYPYY) of the Na(+)-K(+)-adenosinetriphosphatase (ATPase) beta 1-subunit ectodomain has been mutagenized to study its possible role in alpha/beta-assembly and sodium pump function. Single as well as double tyrosine mutants (tyrosine to phenylalanine: Y to F) of Xenopus laevis beta 1-subunits are able to associate with alpha 1-subunits and form functional Na-K pumps at the plasma membrane that are indistinguishable from wild-type alpha 1, beta 1-Na-K pumps (as assessed by measurements of ouabain binding, 86Rb flux, Na-K pump current, and activation by external potassium). In contrast, a single proline mutation (proline to glycine: P244G) reduced by > 90% the proper assembly and function of Na(+)-K(+)-ATPase, despite a normal rate of synthesis and core glycosylation. Our data indicate that proline-244 plays a critical role in the proper folding of the beta-subunit and its ability to associate efficiently with the alpha 1-subunit in the endoplasmic reticulum.
Keywords
Animals
Biological Transport
Cell Membrane/metabolism
*Mutation
Na(+)-K(+)-Exchanging ATPase/*genetics/*metabolism
Oocytes/metabolism
Peptide Fragments/*genetics
Proline/*genetics
Xenopus laevis
Pubmed
Web of science
Create date
24/01/2008 13:28
Last modification date
20/08/2019 14:06