For the first time, biologists have studied in detail how the human immunodeficiency virus (HIV) multiplies. Scientists have traced how the pathogen integrates its genome into the DNA of the host cell, and found unexpected details. This information will assist in the development of new drugs. Perhaps with its help it will be possible to finally defeat the deadly infection.
The achievement is described in scientific articlepublished in Science by a group led by Wesley Sandqvist (Wesley Sundquist) from the University of Utah.
HIV is one of the most studied viruses in the world. Nevertheless, we still do not know everything about him. It is especially difficult to study the process of its reproduction.
Recall that viruses are not able to reproduce on their own. To create their own copies, they take over control of the infected cell’s systems. Similarly, a computer virus can force an infected computer to create copies of an uninvited guest and send them to different addresses.
HIV belongs to RNA viruses. This means that his genome is not stored in DNA, but in RNA. To multiply, the pathogen rewrites information from RNA to DNA (a process called reverse transcription). It inserts this piece of DNA into the host’s chromosome (this is called integration). As a result, the genome of the infected cell contains commands that force it to produce new copies of the virus.
This process takes place deep in the nucleus of the cell, where its DNA is stored. This is why it is difficult to trace it.
Left is an electron microscope image of the capsid of the virus. On the right is a diagram of its structure.
The authors of the new article have done almost impossible. They created an artificial environment outside the living cell in which HIV performs reverse transcription and integration. This allowed for the first time to study this process in detail.
And, of course, the latest microscopy methods played a role. HIV consists of an elongated protein shell (capsid) in which a strand of RNA is hidden. The capsid is only 130 nanometers long. Nevertheless, the researchers discerned not only the virus envelope itself, but also each of the 240 protein “blocks” that make up it.
It is generally believed that the main role of the capsid is to protect the fragile contents from external influences. However, the new study revealed something unexpected.
“Our data show that the viral capsid plays an active and irreplaceable role in efficient reverse transcription.” explains Sandquist. “This is different from what is written in the textbooks.”
–The capsid of the virus serves as an envelope for the RNA strand (shown in blue). But, as it turned out, it is also necessary for the reproduction of the virus.
This means that drugs that attack the envelope of the virus can suppress the growth of the pathogen. This path may lead to the development of new effective drugs for HIV.
Recall that modern medicines prevent the virus from multiplying, but do not kill it. Therefore, HIV-infected patients are forced to take medicine all my lifeto prevent the virus from multiplying, infecting the immune system and causing AIDS.
Perhaps unprecedentedly detailed observations of this pathogen will allow the development of drugs that will rid patients of the pathogen forever. They can also help with vaccine development from a deadly virus.
By the way, earlier News.Ru talked about first 3D animation virus activity.
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