By developing the ability to follow single viruses as they assemble, it is possible to identify and characterize discrete steps in viral assembly. The earliest stages of this work established the criteria to be used in determining if a single virion, in this case of HIV-1, is being observed. This was followed by establishing criteria for determining and characterizing the packing of various components at the plasma membrane, for example the packing of Gag, the recruitment of the genome. This current project carries the work to the next level of identifying many more partial reactions in the process of viral assembly: When is the genome recruited? What is the interaction between the genome and Rev for packing, between the genome and Gag for packing? What determines the ability of the membrane to bend outward - is it just packing of Gag or are there additional factors? When are does the protease become active, what determines the apparent specificity of cleavage steps? When does the virion septate from the cell and, how do each of these steps inter-relate? Must the membrane bend to a certain degree to attain a sufficient proximity for the protease to activate or is it sufficient for Gag to pack to a critical spacing? What are the role(s) of the host ESCRT proteins? Do they simply facilitate budding or do they accelerate the assembly rate? With these assays of assembly at the level of the single virion, it becomes possible to final describe and define the process of assembly.

Public Health Relevance

Viruses are a major threat to human health. This work has developed the ability to follow single viruses assembling in living cells. By elucidating the procedure of assembly, in this case for HIV-1, it opens the possibility of targeting these steps for disruption.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI089844-04
Application #
8479309
Study Section
Special Emphasis Panel (ZRG1-BST-F (04))
Program Officer
Stansell, Elizabeth H
Project Start
2010-07-15
Project End
2014-06-30
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
4
Fiscal Year
2013
Total Cost
$393,179
Indirect Cost
$160,529
Name
Rockefeller University
Department
Biology
Type
Other Domestic Higher Education
DUNS #
071037113
City
New York
State
NY
Country
United States
Zip Code
10065
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Bleck, Marina; Itano, Michelle S; Johnson, Daniel S et al. (2014) Temporal and spatial organization of ESCRT protein recruitment during HIV-1 budding. Proc Natl Acad Sci U S A 111:12211-6
Jouvenet, Nolwenn; Simon, Sanford M; Bieniasz, Paul D (2011) Visualizing HIV-1 assembly. J Mol Biol 410:501-11
Jouvenet, Nolwenn; Zhadina, Maria; Bieniasz, Paul D et al. (2011) Dynamics of ESCRT protein recruitment during retroviral assembly. Nat Cell Biol 13:394-401