Structure of the 5th transmembrane segment of the Na,K-ATPase alpha subunit: a cysteine-scanning mutagenesis study

Details

Serval ID
serval:BIB_E27A9F828588
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Structure of the 5th transmembrane segment of the Na,K-ATPase alpha subunit: a cysteine-scanning mutagenesis study
Journal
FEBS Letters
Author(s)
Guennoun  S., Horisberger  J. D.
ISSN
0014-5793 (Print)
Publication state
Published
Issued date
09/2000
Volume
482
Number
1-2
Pages
144-8
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Sep 29
Abstract
To study the structure of the pathway of cations across the Na, K-ATPase, we applied the substituted cysteine accessibility method to the putative 5th transmembrane segment of the alpha subunit of the Na,K-ATPase of the toad Bufo marinus. Only the most extracellular amino acid position (A(796)) was accessible from the extracellular side in the native Na,K-pump. After treatment with palytoxin, six other positions (Y(778), L(780), S(782), P(785), E(786) and L(791)), distributed along the whole length of the segment, became readily accessible to a small-size methanethiosulfonate compound (2-aminoethyl methanethiosulfonate). The accessible residues are not located on the same side of an alpha-helical model but the pattern of reactivity would rather suggest a beta-sheet structure for the inner half of the putative transmembrane segment. These results demonstrate the contribution of the 5th transmembrane segment to the palytoxin-induced channel and indicate which amino acid positions are exposed to the pore of this channel.
Keywords
Acrylamides/pharmacology Amino Acid Sequence Amino Acid Substitution Animals Bufo marinus Cell Membrane/enzymology Cnidarian Venoms/pharmacology *Cysteine Molecular Sequence Data Mutagenesis, Site-Directed Na(+)-K(+)-Exchanging ATPase/*chemistry/genetics/*metabolism Oocytes/physiology Protein Structure, Secondary Protein Subunits Recombinant Proteins/chemistry/metabolism Virulence Factors, Bordetella/pharmacology
Pubmed
Web of science
Open Access
Yes
Create date
24/01/2008 12:38
Last modification date
20/08/2019 16:06
Usage data