Clamping RNA polymerase Ribozyme - Science, 2021 (VIDEO) Simon Fraser University This video is under embargo. Please login to access this video. Caption At the dawn of life, polymerases made from RNA likely replicated RNA genomes and maintained metabolic RNA enzymes essential for life. The clamping RNA polymerase ribozyme uses a specificity primer to recognize an RNA promoter. Once localized, the polymerase rearranges into a processive complex, capable of copying extended regions of template. This promoter recognition and processivity is similar to many aspects of modern promoter dependent transcription and demonstrates how early in evolution RNA genes might have been replicated and expressed. Credit Simon Fraser 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.