Photoreceptor Cells (IMAGE) Michigan Medicine - University of Michigan Caption Rod photoreceptors disassociated from mouse retina expressing green fluorescent protein. Scientists use an NRL gene regulatory element to tag photoreceptor rods and prepare them for transplantation. Amacrine cells in the inner retina are shown in red. Credit University of Michigan Usage Restrictions None 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.