July 24 (UPI) -- Researchers announced Friday that they have discovered an enzyme that helps COVID-19 enter cells in the human body, allowing the infection to grow.
Called non-structural protein 16, or nsp16, the enzyme is produced by the new coronavirus and acts as a "camouflage," tricking human cells into thinking that the virus is "part of its own code and not foreign," the scientists said in an article published Friday by the journal Nature Communications.
The hope is that the enzyme will provide a target for antiviral drugs designed to cure COVID-19, they said.
"Our work not only enhances basic understanding of this particular pathway, but it provides an opportunity to develop novel antivirals against COVID-19 and emerging coronaviral illnesses in future," co-author Yogesh Gupta told UPI.
These drugs would "block the growth" of the coronavirus in the human body, said Gupta, an assistant professor of biochemistry and structural biology at the University of Texas Health Science Center at San Antonio.
COVID-19 uses nsp16 to disguise its RNA so that human cells can't distinguish the virus's RNA from its own -- allowing the coronavirus to replicate and spread through the body, Gupta said.
"The virus effectively uses this pathway to go undetected and protect its genetic material, while at the same time continuing to grow inside the host body," he said.
In addition to describing its role in the development of COVID-19, Gupta and his team also defined the 3D structure of nsp16. This information can be used by scientists to design antiviral drugs for the disease, they said.
These new drugs would be designed to block nsp16 from disguising its RNA, meaning the human immune system would see the virus as foreign and attack it, according to the researchers.
The findings by Gupta and his colleagues add to research published by the journal Science on July 17, which suggested that another non-structural protein created by the new coronavirus, nsp1, also might work to block the human body's immune system response.
"Viruses need to evade or counteract the immune system to establish an infection," the co-author of the earlier study, Konstantin M. J. Sparrer, told UPI.
"Normally, any infection would trigger the expression of hundreds of antiviral proteins," said Sparrer, a researcher at the Institute of Molecular Virology at Ulm University Medical Center in Germany.
He said that because of nsp1, the coronavirus "manipulates its host to promote its own replication, shutting down ... the innate immune system in the process."