Humans have a built-in weapon against HIV, but until recently no one knew how to unlock its potential.
HIV Life Cycle lesson - Easy-to-read info on treating AIDS. Drugs, Forums, Lessons, & News
New HIV treatment - herbal extracts may help increas CD4 and lower virus counts
HIV Antigen Specialists - Find World Class Purified Antigens Great Service!
APOBEC-3G is present in every human cell. It is capable of stopping HIV at the first step of replication, when the retrovirus transcribes its RNA into viral DNA.
The study's authors, led by Xiaojiang Chen of the University of Southern California, were able to show the atomic structure of the active portion of APOBEC-3G.
The discovery suggests how and where the enzyme binds to the viral DNA, mutating and destroying it.
"We understand how this enzyme can interact with DNA," said Chen, a professor of molecular and computational biology at USC. "This understanding provides a platform for designing anti-HIV drugs."
If APOBEC-3G works so well, why do people get AIDS? Because the HIV virus has evolved to encode the protein Vif, known as a "virulence factor," that blocks APOBEC-3G.
With APOBEC-3G out of the way, the RNA of the HIV virus can be successfully transcribed to viral DNA, an essential step for infection and for producing many more HIV viruses.
Chen said his group's research offers important clues on where Vif binds to APOBEC-3G. The knowledge could be used to design drugs that would prevent Vif from binding and allow APOBEC-3G to do its job, Chen said.
That would unlock humans' innate ability to fight HIV.
"We were born with it, and it's there waiting," Chen said.
In addition to fighting HIV, APOBEC-3G can inhibit the Hepatitis B virus. Other members of the APOBEC family serve important roles in antibody maturation, fat metabolism and heart development.
No comments:
Post a Comment