JVI Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Salaün, C.
Right arrow Articles by Heard, J. M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Salaün, C.
Right arrow Articles by Heard, J. M.

Journal of Virology, June 2001, p. 5584-5592, Vol. 75, No. 12
0022-538X/01/$04.00+0   DOI: 10.1128/JVI.75.12.5584-5592.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Transmembrane Topology of PiT-2, a Phosphate Transporter-Retrovirus Receptor

Christine Salaün, Pierre Rodrigues, and Jean Michel Heard*

Laboratoire Rétrovirus et Transfert Génétique, CNRS URA 1930, Institut Pasteur, 75724 Paris, France

Received 27 November 2000/Accepted 16 March 2001

PiT-1 and PiT-2 are related multiple transmembrane proteins which function as sodium-dependent phosphate transporters and as the cell receptors of several oncoretroviruses. Two copies of a homology domain that is found in distantly related species assign these proteins to a large family of phosphate transporters. A current membrane topology model of PiT-1 and PiT-2 predicts 10 transmembrane domains. However, the validity of this model has not been addressed experimentally. We addressed this issue by a comprehensive study of human PiT-2. Evidence was obtained for glycosylation of asparagine 81. Epitope tagging showed that the N- and C-terminal extremities are extracellular. The orientation of C-terminal-truncation mutants expressed in cell-free translation assays and incorporated into microsomal membranes was examined by immunoprecipitation. Data were interpreted with respect to previous knowledge about retrovirus binding sites, to the existence of repeated homology domains, and to predictions made in family members. A model in which PiT-2 has 12 transmembrane domains and extracellular N- and C-terminal extremities is proposed. This model, which differs significantly from previous predictions about PiT-2 topology, may be useful for further investigations of PiT-2 interactions with other proteins and for the understanding of PiT-2 transporter and virus receptor functions.


* Corresponding author. Mailing address: Laboratoire Rétrovirus et Transfert Génétique, Institut Pasteur, 28 rue du Dr. Roux, 75724 Paris, France. Phone: 33 0 1 45 68 82 46. Fax: 33 0 1 45 68 89 40. E-mail: jmheard{at}pasteur.fr.


Journal of Virology, June 2001, p. 5584-5592, Vol. 75, No. 12
0022-538X/01/$04.00+0   DOI: 10.1128/JVI.75.12.5584-5592.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.



This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Mol. Cell. Biol. Microbiol. Mol. Biol. Rev.
Clin. Vaccine Immunol. ALL ASM JOURNALS

Copyright © 2001 by the American Society for Microbiology. All rights reserved.