While it is clear that HIV-1 assembly occurs predominantly on the plasma membrane (PM), the itinerary that the HIV-1 Gag precursor follows to reach this destination remains ill defined. Likewise, the host cell machinery that promotes Gag trafficking to the PM is incompletely understood. We and others have demonstrated that the matrix (MA) domain of Gag regulates targeting to the site of virus assembly, and we discovered that the phosphoinositide PI(4,5)P2 is a key player in directing Gag to the PM. We hypothesize that host factors in addition to PI(4,5)P2 play a vital role in the trafficking of Gag to the PM. In this project, we are defining the role of host cell machinery in Gag trafficking to the PM and in subsequent steps of particle assembly and release. This effort combines virology, biochemistry, cell biology, and imaging techniques. Our overarching goal is to establish a unified view of the mechanism and pathway(s) involved in the late stages of the HIV-1 replication cycle and to develop inhibitors of HIV-1 Gag trafficking, assembly, and release._____ Most of our efforts, and those of our colleagues, with regard to late-acting host factors have focused on factors that promote HIV-1 particle assembly and release. However, we have become increasingly interested in cellular factors that interfere with the late stages of HIV-1 replication. The best-characterized example of a late-acting negative factor is tetherin (BST-2), an interferon-stimulated gene product that restricts viral particle release at the cell surface. Tetherin is counteracted by the HIV-1 Vpu protein and the Nef or Env proteins of certain strains of HIV-2 and simian immunodeficiency virus. Apart from tetherin, however, little is known about the host cell factors that interfere with HIV-1 assembly or release. We are engaged in studying these host proteins, with an initial focus on the T-cell immunoglobulin and mucin domain (TIM) family of phosphatidylserine-binding proteins and ISG15, one of the most strongly upregulated proteins following type 1 interferon stimulation. We recently reported, in collaboration with Dr. Shan-Lu Liu's lab (University of Missouri), that the TIM-family proteins strongly inhibit HIV-1 release by retaining HIV-1 particles on the cell surface through binding to phosphatidylserine on the viral membrane. We will further characterize the mechanism of action by which such host factors restrict HIV-1 particle production, resulting in dimished viral production and replication._____[Corresponds to Freed Project 1 in the July 2016 site visit report of the HIV Dynamics and Replication Program]

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Investigator-Initiated Intramural Research Projects (ZIA)
Project #
1ZIABC011720-01
Application #
9344060
Study Section
Project Start
Project End
Budget Start
Budget End
Support Year
1
Fiscal Year
2016
Total Cost
Indirect Cost
Name
Basic Sciences
Department
Type
DUNS #
City
State
Country
Zip Code
Van Duyne, Rachel; Freed, Eric O (2018) HIV-1 packs in PACSIN2 for cell-to-cell spread. Proc Natl Acad Sci U S A 115:6885-6887
Buttler, Carmen A; Pezeshkian, Nairi; Fernandez, Melissa V et al. (2018) Single molecule fate of HIV-1 envelope reveals late-stage viral lattice incorporation. Nat Commun 9:1861
Waheed, Abdul A; Gitzen, Ariana; Swiderski, Maya et al. (2018) High-Mannose But Not Complex-Type Glycosylation of Tetherin Is Required for Restriction of HIV-1 Release. Viruses 10:
Martins, Angelica N; Ke, Weina; Jawahar, Vaishnavi et al. (2017) Intracellular Reassociation of RNA-DNA Hybrids that Activates RNAi in HIV-Infected Cells. Methods Mol Biol 1632:269-283
Lippincott-Schwartz, J; Freed, E O; van Engelenburg, S B (2017) A Consensus View of ESCRT-Mediated Human Immunodeficiency Virus Type 1 Abscission. Annu Rev Virol :
Urano, Emiko; Miyauchi, Kosuke; Kojima, Yoko et al. (2016) A Triazinone Derivative Inhibits HIV-1 Replication by Interfering with Reverse Transcriptase Activity. ChemMedChem 11:2320-2326
Afonin, Kirill A; Viard, Mathias; Tedbury, Philip et al. (2016) The Use of Minimal RNA Toeholds to Trigger the Activation of Multiple Functionalities. Nano Lett 16:1746-53
Waheed, Abdul A; MacDonald, Scott; Khan, Maisha et al. (2016) The Vpu-interacting Protein SGTA Regulates Expression of a Non-glycosylated Tetherin Species. Sci Rep 6:24934
Mercredi, Peter Y; Bucca, Nadine; Loeliger, Burk et al. (2016) Structural and Molecular Determinants of Membrane Binding by the HIV-1 Matrix Protein. J Mol Biol 428:1637-55
Martins, Angelica N; Waheed, Abdul A; Ablan, Sherimay D et al. (2015) Elucidation of the Molecular Mechanism Driving Duplication of the HIV-1 PTAP Late Domain. J Virol 90:768-79

Showing the most recent 10 out of 11 publications