HIV infection is influenced by dynamin at three independent points in the viral life cycle

Abstract
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 three 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 two 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.

Synopsis
The concept that HIV endocytosis is the rate limiting step for HI...

Source: Traffic - February 28, 2017 Category: Research Authors: Anupriya Aggarwal, Tina L. Hitchen, Lars Ootes, Samantha McAllery, Andrew Wong, Khanh Nguyen, Adam McCluskey, Phillip J. Robinson, Stuart G. Turville Tags: ORIGINAL ARTICLE Source Type: research