Interrelationship between cytoplasmic retroviral Gag concentration and Gag-membrane association.

Autor: Fogarty KH; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, USA; School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA., Berk S; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA., Grigsby IF; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, USA., Chen Y; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA., Mansky LM; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; Department of Diagnostic and Biological Sciences, School of Dentistry, University of Minnesota, Minneapolis, MN 55455, USA; Department of Microbiology, University of Minnesota, Minneapolis, MN 55455, USA. Electronic address: mansky@umn.edu., Mueller JD; Institute for Molecular Virology, University of Minnesota, Minneapolis, MN 55455, USA; School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA; Department of Biomedical Engineering, University of Minnesota, Minneapolis, MN 55455, USA. Electronic address: mueller@physics.umn.edu.
Jazyk: angličtina
Zdroj: Journal of molecular biology [J Mol Biol] 2014 Apr 03; Vol. 426 (7), pp. 1611-24. Date of Electronic Publication: 2013 Dec 04.
DOI: 10.1016/j.jmb.2013.11.025
Abstrakt: The early events in the retrovirus assembly pathway, particularly the timing and nature of Gag translocation from the site of protein translation to the inner leaflet of the plasma membrane, are poorly understood. We have investigated the interrelationship between cytoplasmic Gag concentration and plasma membrane association using complementary live-cell biophysical fluorescence techniques in real time with both human T-cell leukemia virus type 1 (HTLV-1) and human immunodeficiency virus type 1 (HIV-1) Gag proteins. In particular, dual-color, z-scan fluorescence fluctuation spectroscopy in conjunction with total internal reflection fluorescence and conventional, epi-illumination imaging were utilized. Our results demonstrate that HTLV-1 Gag is capable of membrane targeting and particle assembly at low (i.e., nanomolar) cytoplasmic concentrations and that there is a critical threshold concentration (approaching micromolar) prior to the observation of HIV-1 Gag associated with the plasma membrane. These observations imply fundamental differences between HIV-1 and HTLV-1 Gag trafficking and membrane association.
(Copyright © 2013 Elsevier Ltd. All rights reserved.)
Databáze: MEDLINE
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