Helmholtz Gemeinschaft

Search
Browse
Statistics
Feeds

HIV-1 Gag release from yeast reveals ESCRT interaction with the Gag N-terminal protein region

[thumbnail of Original Article]
Preview
PDF (Original Article) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
5MB
[thumbnail of Supporting Information]
Preview
PDF (Supporting Information) - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader
13MB

Item Type:Article
Title:HIV-1 Gag release from yeast reveals ESCRT interaction with the Gag N-terminal protein region
Creators Name:Meusser, B., Purfuerst, B. and Luft, F.C.
Abstract:The HIV-1 protein Gag assembles at the plasma membrane and drives virion budding, assisted by the cellular endosomal-complex-required-for-transport (ESCRT) proteins. Two ESCRT proteins, TSG101 and ALIX, bind to the Gag C-terminal p6 peptide. TSG101 binding is important for efficient HIV-1 release, but how ESCRTs contribute to the budding process and how their activity is coordinated with Gag assembly is poorly understood. Yeast, allowing genetic manipulation that is not easily available in human cells, has been used to characterize the cellular ESCRT function. Previous work reported Gag budding from yeast spheroplasts, but Gag release was ESCRT independent. We developed a yeast model for ESCRT-dependent Gag release. We combined yeast genetics and Gag mutational analysis with Gag-ESCRT binding studies and the characterization of Gag-plasma-membrane binding and Gag release. With our system, we identified a previously unknown interaction between ESCRT proteins and the Gag N-terminal protein region. Mutations in the Gag plasma-membrane-binding matrix domain that reduced Gag-ESCRT binding increased Gag-plasma-membrane binding and Gag release. ESCRT knockout mutants showed that the release enhancement was an ESCRT-dependent effect. Similarly, matrix mutation enhanced Gag release from human HEK293 cells. Release enhancement partly depended on ALIX binding to p6, although binding-site mutation did not impair WT Gag release. Accordingly, the relative affinity for matrix compared to p6 in GST-pull-down experiments was higher for ALIX than for TSG101. We suggest that a transient matrix-ESCRT interaction is replaced when Gag binds to the plasma membrane. This step may activate ESCRT proteins and thereby coordinate ESCRT function with virion assembly.
Keywords:Gag, Human Immunodeficiency Virus (HIV), Endosomal Sorting Complexes Required For Transport (ESCRT), Yeast, Saccharomyces Cerevisiae, Virus Releas, Matrix, ALIX, Bro1, Plasma Membrane
Source:Journal of Biological Chemistry
ISSN:0021-9258
Publisher:American Society for Biochemistry and Molecular Biology
Volume:295
Number:52
Page Range:17950-17972
Date:25 December 2020
Official Publication:https://doi.org/10.1074/jbc.RA120.014710
PubMed:View item in PubMed

Repository Staff Only: item control page

Downloads

Downloads per month over past year

Open Access
MDC Library