FRIDAY, SEPTEMBER 30, 2016

Study shows Rab protein crucial for HIV-1 replication

Study shows Rab protein controlling HIV-1 replication | Courtesy of npowetenschap.nl
A recent study revealed that Rab protein is crucial for HIV-1 replication, which requires that the virus’s components coordinate inside the immune cell’s plasma membrane.

The HIV-1 replication requires these coordinated movements to reach virions, where the cells are ultimately assembled and released. Now researchers can see that the Rab protein is in command of intracellular trafficking, which supports the assembly of HIV-1 and urges the cell to produce high levels of lipid, an important membrane.

The new HIV-1 particles gather at specialized sites located within the plasma membrane. These sites are rich with PIP2, a phospholipid component part of the membrane that creates Pr55Gag (Gag), a viral protein that is important in directing HIV-1 assembly.

Scientists have suggested certain cell secretion pathways are needed for this process to occur, which is why researchers from the University of Buenos Aires conducted the study to see whether Rab27a may fulfill the role of a traffic controller within the cell. Rab is a protein that controls membrane-bound deliveries from compartments (endosomes) to plasma membrane.

The researchers discovered that immune cells without Rab do not show as much viral replication of HIV-1. These unique cells have reduced PIP2 levels, which results in Gag proteins cannot create assembly sites for the virus. This research may be crucial to determining whether a manipulating endosomal traffic would be an efficient treatment for HIV-1.

Further details are available in The Journal of Cell Biology.