Scientists have for the first time peeled open the virus — that can lead to AIDS — from its shell raising, giving a priceless insight into how it can be stopped from infecting millions across the globe every year.
A team of researchers from the University of Pittsburgh School of Medicine have announced that they have peeled open HIV’s outer coating and discovered 4-million-atom structure inside the protein shell.
The findings, researchers say, will ultimately lead the way to fending off an often-changing virus that has been very hard to conquer.
It’s been 30 years since the AIDS epidemic spread to every corner of the world killing nearly 30 million people, infecting more than 60 million. There is still no vaccine or cure for it.
Scientists say developing an effective vaccine to prevent HIV infection is one of the most daunting challenges ever faced. One of the main reason for this is that HIV is an incredibly elusive virus.
HIV is among the most mutating viruses.
Scientists have long struggled to decipher how the HIV capsid shell is chemically put together.
Senior author Peijun Zhang, department of structural biology, University of Pittsburgh School of Medicine said, “The capsid is critically important for HIV replication, so knowing its structure in detail could lead us to new drugs that can treat or prevent the infection,” she said.
“This approach has the potential to be a powerful alternative to our current HIV therapies, which work by targeting certain enzymes, but drug resistance is an enormous challenge due to the virus’ high mutation rate.”
Previous research has shown that the cone-shaped shell is composed of identical capsid proteins linked together in a complex lattice.
But the shell is non-uniform and asymmetrical; uncertainty remained about the exact number of proteins involved and how the hexagons of six protein subunits and pentagons of five subunits are joined.
Standard structural biology methods to decipher the molecular architecture were insufficient because they rely on averaged data, collected on samples of pieces of the highly variable capsid to identify how these pieces tend to go together.
“The capsid is very sensitive to mutation, so if we can disrupt those interfaces, we could interfere with capsid function,” Dr Zhang said. “The capsid has to remain intact to protect the HIV genome and get it into the human cell, but once inside it has to come apart to release its content so that the virus can replicate. Developing drugs that cause capsid dysfunction by preventing its assembly or disassembly might stop the virus from reproducing.”
“By using a combination of experimental and computational approaches, this team of investigators has produced a clearer picture of the structure of HIV’s protective covering,” said the National Institutes of Health’s Michael Sakalian.
“The new structural details may reveal vulnerabilities that could be exploited by future therapeutics.”
Source: The Times of India
