Nucleoporins and Transcription (IMAGE) Salk Institute Caption Polytene chromosomes -- giant chromosomes found in the salivary glands of fruit flies -- revealed that nucleoporins pull double duty as transcription factors regulating the activity of genes active during early development. Image: Credit Courtesy of Dr. Maya Capelson, Salk Institute for Biological Studies 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.