Point-of-View www.landesbioscience.com RnA Biology 295

Multi-subunit RNA polymerases are the enzymes that perform transcription in all living organisms and that have emerged before the divergence of domains of life. The structures of cat-alytic cores and their functions during elongation step of transcription cycle are very similar for all multi-subunit RNA polymerases. In contrast, the mecha-nisms for terminating the RNA synthe-sis have seemingly diverged in modern RNA polymerases. However, the recent finding that, much like during bacterial transcription, RNA secondary structure is involved in termination by eukaryotic RNA polymerase III (pol III), suggest