Scientists identify proteins in Zika that can cause microcephaly

Scientists from USC have identified two proteins within the Zika virus that they believe could be the reason that infected mothers are giving birth to babies with microcephaly.

The Centers for Disease Control and Prevention has concluded that Zika causes microcephaly - an abnormally small head - but scientists have been unsure about how it happens. The USC researchers, who published their study in the journal Cell Stem Cell, found that two of the 10 proteins in the Zika virus appear to be the culprits. 

The science is complicated, but in essence the proteins - dubbed NS4A and NS4B - work together to inhibit brain development in fetuses, which in turn results in a baby with a smaller than average head.

"So we have now [a] target for treatment, so we could actually develop the drug that ultimately can cure microcephaly," said Jae Jung, the leader of the study and chair of the Department of Molecular Microbiology and Immunology at USC's Keck School of Medicine. 

Dr. Hengli Tang, a virologist at Florida State University, agrees. He's contributed other research on Zika and thinks that this is "a significant development because it pinpoints the molecular players that [cause] the disease in fetus brains, and presumably can provide more precise or novel targets for therapeutics."

Microcephaly can cause a variety of developmental issues, such as speech problems and a diminished ability to learn and function in daily life, according to the CDC.

Going forward, scientists could develop drugs that target NS4A and NS4B in a way that’s similar to how HIV is targeted by drugs, said Jung.

That could take a long time, he said: "It takes many, many years to understand ... the specific pathway of viruses."

But compared with research  into HIV, Jung said, research on Zika is moving along quickly.

"It took 10 years to develop the HIV drug and after 40 years we don't even have a vaccine against HIV," he said. "But [with] Zika, we already have a potential vaccine" and other Zika-related drugs are in development.

"So, actually the Zika studies are literally 10 times faster than any other viral infection study," said Jung.

Earlier this month, the federal government started the first human trials of a possible Zika vaccine.