Baylor College of Medicine researchers said they discovered a protein found in the virulent avian flu virus strain called H5N1 forms tiny tubules in which it "hides" the pieces of double-stranded RNA formed during viral infection.

Professor B.V. Venkataram Prasad and Zachary Bornholdt, now with the Scripps Research Institute, discovered two portions of the protein NS1 combine to form tiny tubules in which the double-stranded RNA is hidden from the immune system.

"Once we confirm the importance of this structural information, we should be able to design drugs to block this action," Prasad said. "There are other things the protein could do to interfere with different immune mechanisms. We don't know if this is the only mechanism or if there are others that also come into play during influenza virus infection."

The study, funded by the National Institutes of Health and the Robert Welch Foundation, appears in the online edition of the journal Nature.