JVI Figure table search 04
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
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 Wang, H
Right arrow Articles by Kabat, D
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wang, H
Right arrow Articles by Kabat, D

 Previous Article  |  Next Article 

J Virol. 1991 December; 65(12): 6468-6477

Plasma membrane receptors for ecotropic murine retroviruses require a limiting accessory factor.

H Wang, R Paul, R E Burgeson, D R Keene and D Kabat

Department of Biochemistry and Molecular Biology, School of Medicine, Oregon Health Sciences University, Portland 97201-3098.

ABSTRACT

A retroviral vector was used to express various amounts of the receptor (ecoR) for ecotropic host range murine retroviruses on naturally barren hamster, mink, and human cells. These cells and murine cells were then incubated for 2 h with dilutions of a helper-free ecotropic retrovirus that encodes human growth hormone, and the number of infected cells was later determined by growth hormone-specific immunofluorescence. For all cells under the conditions of these studies, virus adsorption was the limiting step of infection and the cellular capacities for infection were unsaturated either at cell surfaces or at intracellular sites. Thus, infections occurred at low multiplicities of infection per cell and were directly proportional to virus and cell concentrations, and only a small percentage (ca. 5%) of the infectious virions became adsorbed from the medium during the 2-h incubations. Although increasing the adsorption by raising virus or cell concentrations results in more infections in the cultures, increasing adsorption by raising the number of ecoR above a low threshold had no effect on infections. Thus, cells with a low number of ecoR were infected as efficiently as highly adsorbing cells that contained many times more ecoR. To reconcile these results, we conclude that only a small, set number of cell surface ecoR can be functional for infection and that all excess ecoR can only bind virus into an unsalvageable pool. Therefore, retroviral receptors on single cells are functionally diverse. Our results suggest that activity of ecoR in infection requires a limiting second cellular component.

J Virol. 1991 December; 65(12): 6468-6477




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 © 1991 by the American Society for Microbiology. All rights reserved.