Researchers identify a protein that viruses use as gateway into cells

Enlarge / An electron micrograph of multiple copies of the chikungunya virus. (credit: CDC/Cynthia Goldsmith)

The word “chikungunya” (chik-en-gun-ye) comes from Kimakonde, the language spoken by the Makonde people in southeast Tanzania and northern Mozambique. It means “to become contorted,” because that’s what happens to people who get infected. The contortion is a result of severe and debilitating joint pain. Chikungunya was first identified in Tanzania in 1952, but by now cases have been reported around the globe. There is no cure; the CDC recommends that “travelers can protect themselves by preventing mosquito bites.”

Chikungunya is only one of a family of viruses transmitted through mosquitoes for which we have no targeted treatment. This may partially be due to the fact that we didn’t know how they get into our cells. But for chikungunya, we've just found one of the proteins responsible.

Identification via deletion

Researchers used the CRISPR-Cas9 DNA editing system to delete more than twenty-thousand mouse genes—a different one in each cell in a dish. Then they added chikungunya to the dish, isolated the cells that didn’t get infected, and looked to see which gene they lacked. This gene would encode a protein required for viral infection, since infection didn’t happen in its absence.