Find impregnable areas for HIV
The AIDS virus inserts its genetic material into the genome of the infected cell. In a recent paper, scientists at the German Centre for Research on Cancer found for the first time that the process of integration into the human genome prevents the virus only a few specific sites. What do these particular sites?. According to thi s work finding may be useful for the development of new specific drugs against AIDS.
Like all retroviruses, the AIDS virus (HIV), integrates its DNA into the genome of the infected cell. Usually the preferred sites of HIV integration are active genes transcribed often. This is advantageous for the virus because here is where a large number of enzymes that are responsible for viral replication. That is, the virus takes advantage and uses the cellular machinery for their own benefit.
Where is inserted HIV virus in the human genome? This question is crucial because depending on the position, this process can result in permanent activation of oncogenes or other damage. Therefore, the researchers looked in detail over 46,000 known sites of HIV integration.
So far, researchers have been convinced that HIV has a special preference for transcription start sites of genes. At these sites there is an abundance of enzymes that the virus needs. However, analysis of databases data showed a contrasting picture. Although HIV uses many of these sites near transcription start sites, the researchers found that such sites rarely or never used for virus integration.
“For the first time we have very clearly defined areas in the human genome where HIV rarely integrated.” Must be a reason why HIV evades these sites. “We assume that there is a special mechanism at work that blocks viral way for these sites. “” On the other hand, it is possible that some factor that HIV needs for integration is not on these sites. ”
A viral enzyme called integrase, and responsible for integrating the viral DNA into the genome of the infected cell, is an interesting candidate. This enzyme is located in the center of the search for better AIDS treatment. New HIV treatments attack the virus from different angles with different drugs: reverse transcriptase inhibitors prevent viral genome copy. Protease inhibitors block the maturation of new viral proteins. Add a drug that blocks the integration could help in this effort.
Scientists agree that the HIV virus can be combated by avoiding the integration of viral genetic material into the DNA of host cells. The prevention of these substances, called integrase inhibitors have been used in recent years, but virus have begun to escape its effects through mutations. Therefore, virologists are seeking new approaches to blocking this key enzyme of the virus. The mechanism that prevents HIV integration sites ESTs “impregnable” could be a model molecular development of these substances.
