False-colored scanning electron micrograph of HIV particles (yellow) infecting a human H9 T cell (blue, turquoise)
In some ways, HIV resembles a minimalist painter, using a few basic components to achieve dramatic effects. The virus contains just nine genes encoding 15 proteins, which wreak havoc on the human immune system. But this bare bones approach could have a fatal flaw. Lacking robust machinery, HIV hijacks human proteins to propagate, and these might represent powerful therapeutic targets.
Using a technique called RNA interference to screen thousands of genes, Harvard Medical School researchers have now identified 273 human proteins required for HIV propagation. The vast majority had not been connected to the virus by previous studies. The work appears online in Science Express on Jan. 10.
A report in the January issue of Cell Metabolism, a publication of Cell Press, provides new evidence explaining how stem cells known as satellite cells contribute to building muscles up in response to exercise. These findings could lead to treatments for reversing or improving the muscle loss that occurs in diseases such as cancer and AIDS as well as in the normal aging process, according to the researchers.