Discriminator Element (1 of 2) (IMAGE) Rutgers University Caption A crystal structure of a bacterial transcription initiation complex reveals that the initiation factor recognizes the promoter -10 element and promoter discriminator element through interactions that include the unstacking of DNA bases and their insertion into pockets formed by residues of [Interactions of σ (yellow) with the -10 element (blue) and discriminator element (light blue) are illustrated. DNA bases that are unstacked and inserted into pockets are indicated with cyan boxes. An amino acid of σ that can be crosslinked to discriminator position -5 is indicated in green.] Credit Yu Zhang and Richard H. Ebright, Rutgers University Usage Restrictions Permission is granted to reproduce the image in connection with news coverage of this story. All other rights are reserved. 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.