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bioRxiv · 10.1101/2021.02.10.430663

Full assembly of HIV-1 particles requires assistance of the membrane curvature factor IRSp53.

Inamdar, K.·Tsai, F.-C.·dePoret, A.·Dibsy, R.·Manzi, J.·Merida, P.·Muller, R.·Lappalainen, P.·Roingeard, P.·Mak, J.·Bassereau, P.·Favard, C.·MURIAUX, D.
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Abstract

During HIV-1 particle formation, the requisite plasma membrane curvature is thought to be solely driven by the retroviral Gag protein. Here, we reveal that the cellular I-BAR protein IRSp53 is required for the progression of HIV-1 membrane curvature to complete particle assembly. Partial gene editing of IRSp53 induces a decrease in viral particle production and a viral bud arrest at half completion. Single molecule localization microscopy at the cell plasma membrane shows a preferential localization of IRSp53 around HIV-1 Gag assembly sites. In addition, we observe the presence of IRSp53 in purified HIV-1 particles. Finally, HIV-1 Gag protein localizes preferentially to IRSp53 I-BAR domain induced curved membranes on giant unilamellar vesicles. Overall, our data reveal a strong interplay between IRSp53 I-BAR and Gag at membranes during virus assembly. This highlights IRSp53 as a crucial host factor in HIV-1 membrane curvature and its requirement for full HIV-1 particle assembly.

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Inamdar, K., Tsai, F.-C., dePoret, A., Dibsy, R., Manzi, J., Merida, P., Muller, R., Lappalainen, P., Roingeard, P., Mak, J., Bassereau, P., Favard, C., MURIAUX, D.. 2021-02-10. Full assembly of HIV-1 particles requires assistance of the membrane curvature factor IRSp53.. https://doi.org/10.1101/2021.02.10.430663

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