- How does the nCoV identify its human host cell?
- Reference: https://science.sciencemag.org/content/367/6485/1444
- In this paper, Yan and colleagues set out to characterize the structure of the human molecule that binds to the viral protein and grants entry into the cell. Cells in the lungs, kidneys and intestine have a protein called Angiotensin Converting Enzyme-2 (ACE2) on their surface. This protein is responsible for processing a hormone called Angiotensin, which enlarges blood vessels surrounding these cells. The coronavirus has proteins called Spike proteins (spiky things you see on coronavirus images) which bind to this ACE2 and gains entry into the cell. If we can block this event from happening, we could in principle stop viral entry and infection. Understanding how ACE2 and spike protein look together would therefore act as a guide in our pursuit for therapy. Research by Yan and colleagues does exactly this. We now have, for the first time, a picture of the full human ACE2 receptor and a portion of the n-CoV spike protein that is responsible for binding to this receptor. Besides, this work also identifies key differences in the modes of entry between the novel coronavirus and the virus that was responsible for the previous SARS outbreak. These differences could be responsible to the 10-15-fold higher affinity for the nCoV over the previous coronavirus (research from Wrapp and colleagues). Such details offer important insight into the mechanism by which nCoV infects a human cell opening up novel avenues for the development of better therapy.
- Summary by: Manoj Kumar Rathinaswamy, Graduate Student at University of Victoria, Canada.
Photo credit: National Cancer Institute on Unsplash