Pioneer Transcription Factor Rap1 (IMAGE) Ecole Polytechnique Fédérale de Lausanne Caption The pioneer transcription factor Rap1 pries open compact chromatin structure to activate genes. Credit Beat Fierz, EPFL Usage Restrictions Media purposes only. Commercial usage restricted; by permission only. 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.