Scientists identify genes that shut down HIV-1

Scientists identify genes that shut down HIV-1

The HIV-1 virus consists of only nine genes. To replicate its genome, HIV-1 requires a host cell. Once the virus has infected a cell, it takes over certain native cellular processes so that it can replicate. Ultimately, the infected host cell produces new virions carrying the HIV-1 genome. These virions, in turn, search for new cells to infect, continuing the cycle of infection.

Nef, one of nine primary proteins expressed by HIV, induces numerous changes in the host cell that increase the virus’s ability to infect new cells. One of its jobs is to sequester SERINC3 and SERINC5 (host transmembrane proteins) so that these cellular proteins do not reach the surface of the cell and cannot be incorporated into newly formed virions. In the absence of Nef, upon leaving the cell, virions incorporate the SERINC3 and SERINC5 proteins into the viral envelope and are rendered unable to infect new target cells.

These virions are able to latch onto potential host cells but the HIV-1 genome can’t pass through the viral envelope when SERINC3 and SERINC5 are present. Somehow these proteins are blocking the release of the virus’s genome, essentially keeping the virus from spreading.

These findings demonstrate that the SERINC proteins probably inhibit the infectivity of all retroviruses, even those most distantly related to HIV


Item has a rating of 5 1 vote