This image is a scanning electron micrograph of HIV-1 budding from a cultured cell. The secrets of the AIDS virus may all come down to a protein named ALIX. Researchers have devised a way to watch newly forming AIDS particles emerging or “budding” from infected human cells without interfering with the process. The method shows that a protein named ALIX (which stands for “alg-2 interacting protein x”) gets involved during the final stages of virus replication, not early on, as was believed. ALIX assists in separating new virus buds from a cell. These buds repeat the replication process and further infect their host. “We watch one cell at a time” and use a digital camera and special microscope to make movies and photos of the budding process, says virologist Saveez Saffarian, a scientist at the University of Utah, and co-author of a paper on HIV budding published recently in the journal PLOS ONE.
Image credit: CDC