New coronavirus protein reveals drug target

Researchers have identified a potential drug target in a newly mapped protein of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19).

Drugs previously developed to treat the earlier SARS outbreak could now be developed as effective drugs against COVID-19, according to a Northwestern University news release on Monday, reports Xinhua.

The newly mapped protein is called Nsp15, which is conserved among coronavirus and is essential in their lifecycle and virulence, said Andrzej Joachimiak, a professor at the University of Chicago.

“Initially, Nsp15 was thought to directly participate in viral replication, but more recently, it was proposed to help the virus replicate possibly by interfering with the host’s immune response,” Andrzei added.

The structure was solved by a team including the University of Chicago, the U.S. Department of Energy’s (DOE) Argonne National Laboratory, Northwestern University Feinberg School of Medicine and the University of California, Riverside School of Medicine (UCR).

The protein Nsp15 from Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is 89% identical to the protein from the earlier outbreak of SARS-CoV. 

Studies published in 2010 on SARS-CoV revealed that inhibition of Nsp15 can slow viral replication. This suggests drugs designed to target Nsp15 could be developed as effective drugs against COVID-19.

"The Nsp15 protein has been investigated in SARS as a novel target for new drug development, but that never went very far because the SARS epidemic went away, and all new drug development ended,” said Karla Satchell, professor of microbiology-immunology at the NU.

“Some inhibitors were identified but never developed into drugs. The inhibitors that were developed for SARS now could be tested against this protein," she added.

Rapid upsurge and proliferation of the novel coronavirus, or SARS-CoV-2, also raised questions about how this virus could become far more transmissible as compared to the SARS and MERS coronavirus.

"While the SARS-CoV-2 is very similar to the SARS virus that caused epidemics in 2003, new structures shed light on the small, but potentially important differences between the two viruses that contribute to the different patterns in the spread and severity of the diseases they cause," said Adam Godzik, a professor of biomedical sciences in the School of Medicine, the University of California Riverside.

Currently, there is no existing drug for COVID-19, but various treatment options, such as utilizing medicines effective in other viral ailments, are being attempted across the world.