Proteins Found That AIDS Virus Preys On

The AIDS virus
has to hijack human proteins to do its damage, but
scientists until now have known only a few dozen of its
targets. On Thursday, Harvard researchers unveiled a
surprisingly longer list, an important first step in
the hunt for new drugs.

HIV is on its
face a simple virus, consisting of just nine genes. Yet it
makes up for that bare-bones structure in a sinister and
complex way -- by literally taking over the cellular
machinery of its victims so it can multiply and then
destroy.

The proteins it
exploits have been dubbed HIV dependency factors, and 36
had been discovered. The new research, published online
Thursday by the journal Science, found 273 of
these potential HIV targets.

Led by geneticist
Stephen Elledge of Boston's Brigham and Women's
Hospital, the team used a technique called RNA interference
that can disrupt a gene's ability to do its job and
make a protein. One by one, they disrupted thousands
of human genes in test tubes, dropped in some HIV, and
watched what happened. If HIV couldn't grow well, it
signaled the protein that the gene that had failed to
produce must be the reason.

It will take far
more research to figure out the role each of these
proteins plays in HIV's life cycle.

But most of
today's AIDS drugs work by targeting the AIDS virus itself.
In August, the government approved sale of the first drug
that works by blocking an HIV dependency factor, a
cellular doorway called CCR5. The hope is that this
longer list of those factors will point toward spots
where similar drugs might work. (AP)