A Colorful Expression (IMAGE) Brown University Caption Finding cells that have bone-making potential is more efficiently done by looking at the genes they express -- ALPL, in this case -- than at proteins on their surface. The bone matrix being produced by cells is stained red in samples of cells that are sorted for not expressing ALPL (left), sorted for expressing ALPL (right), and left as an unsorted control (center). Credit Darling lab/Brown University 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.