A Red Flag (IMAGE) Rockefeller University Caption Researchers engineered cultured cells to contain a red marker that moves into the nucleus upon HCV infection. Nothing happened when normal cells were exposed to HCV (top), but when the researchers expressed the protein SEC14L2, some nuclei changed color from blue to purple (bottom). Credit Laboratory of Virology and Infectious Disease at The Rockefeller University/<em>Nature</em> Usage Restrictions This image may only be used illustrate the research described in the accompanying release. License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.