Exit Sandman (IMAGE) Picower Institute at MIT Caption Staining of cortex glia show much less of the protein sandman (green) in the zyd mutant flies (right) vs. the typical "wild-type" flies (left). Credit Shirley Weiss/Troy Littleton/MIT Usage Restrictions with credit 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.