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Updated: Mar 1, 2026

Visualization of HIV-1 Gag Binding to Giant Unilamellar Vesicle GUV Membranes
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Published on: July 28, 2016

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Phosphatidylinositol (4,5)-bisphosphate-mediated pathophysiological effect of HIV-1 Tat protein

Bruno Beaumelle1, Petra Tóth2, Olfat A Malak3

  • 1Institut de Recherche en Infectiologie de Montpellier, UMR 9004 CNRS, Université Montpellier, Montpellier, France.

Biochimie
|May 28, 2017
PubMed

Human immunodeficiency virus (HIV)-infected cells actively release the transcriptional activator (Tat) viral protein that is required for efficient HIV gene transcription. Extracellular Tat is able to enter uninfected cells. We recently reported that internalized Tat escapes endosomes to reach the cytosol and is then recruited to the plasma membrane by phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). As a consequence, Tat strongly impairs different critical cellular functions in several cell types. Here we will review recent evidences showing that Tat, by affecting the interaction of key cellular effectors with PtdIns(4,5)P2, blocks exocytosis from neuroendocrine cells, perturbs the synaptic vesicle exo-endocytosis cycle, prevents efficient phagocytosis by macrophages, and alters potassium channel activity in cardiac cells. Potential mechanistic aspects of Tat effects on these cellular processes will be discussed.

Keywords:
HIV-1 TatNeurosecretionPhagocytosisPotassium channelsPtdIns(4,5)P(2)

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