A Critical Link in the Assembly and Spread of HIV-1
To multiply and spread infections, viruses must enter and exit cells. Once inside a cell, many viruses take over the cell’s machinery to produce new viral particles and release them into the surroundings. Some viruses—including HIV-1—exit the cell in a manner that wraps them in membrane from the host cell. A virus protein called Gag is required for the release of HIV-1 and other retroviruses. In some cases, Gag proteins bind directly to members of the NEDD4 protein family to facilitate virus release. However, the Gag protein from HIV-1 does not appear to interact directly with NEDD4 proteins, so it was not clear how this virus connects to these proteins. In a study with laboratory-grown human cells, University of Utah researchers show that members of another human protein family called the Angiomotins are required to wrap the HIV-1 virus in membrane, act as a link between Gag and NEDD4L (one member of the NEDD4 family), and are necessary for efficient virus release from human cells.