HIV infection is influenced by dynamin at 3 independent points in the viral life cycle.
CD4 T cells are important cellular targets for HIV-1, yet the primary site of HIV fusion remains unresolved. Candidate fusion sites are either the plasma membrane or from within endosomes. One area of investigation compounding the controversy of this field, is the role of the protein dynamin in the HIV life cycle. To understand the role of dynamin in primary CD4 T cells we combined dynamin inhibition with a series of complementary assays based on single particle tracking, HIV fusion, detection of HIV DNA products and active viral transcription. We identify 3 levels of dynamin influence on the HIV life cycle. Firstly, dynamin influences productive infection by preventing cell cycle progression. Secondly, dynamin influences endocytosis rates and increases the probability of endosomal fusion. Finally, we provide evidence in resting CD4 T cells that dynamin directly regulates the HIV fusion reaction at the plasma membrane. We confirm this latter observation using 2 divergent dynamin modulating compounds, one that enhances dynamin conformations associated with dynamin ring formation (ryngo-1-23) and the other that preferentially targets dynamin conformations that appear in helices (dyngo-4a). This in-depth understanding of dynamin's roles in HIV infection clarifies recent controversies and furthermore provides evidence for dynamin regulation specifically in the HIV fusion reaction.
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Anupriya
A
Aggarwal
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Tina L
TL
Hitchen
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Lars
L
Ootes
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Samantha
S
McAllery
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Andrew
A
Wong
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Khanh
K
Nguyen
Centre for Chemical Biology, Chemistry, School of Environmental and Life Sciences, The University of Newcastle, Callaghan, Australia.
Adam
A
McCluskey
Children's Medical Research Institute, The University of Sydney, New South Wales, Australia.
Phillip J
PJ
Robinson
The Kirby Institute, University of New South Wales, New South Wales, Australia.
Stuart G
SG
Turville
D002462:Cell Membrane / Q000378:metabolism; D002478:Cells, Cultured; D034281:Dynamins / Q000378:metabolism*; D004705:Endocytosis / Q000502:physiology*; D011992:Endosomes / Q000378:metabolism*; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D053586:Virus Internalization
D034281:Dynamins

ABO blood group antigen; flow cytometry; glycosphingolipids; haematopoietic stem cell transplantation; red blood cell