Structure of the complete elongation complex of RNA polymerase II with basal factors

Abstract

Transcription machinery remains steadfast Eukaryotic transcription of mRNA is a multistep process mediated by RNA polymerase II (Pol II). Pol II combines with several other factors to form an elongation complex that promotes transcription elongation. Ehara et al. determined the high-resolution structure of the elongation complex by means of x-ray crystallography and cryo-electron microscopy (see the Perspective by Fouqueau and Werner). Multiple elongation factors are distributed on a wide surface of Pol II and establish an RNA exit path and DNA entry or exit tunnels, which facilitate nascent transcript transfer and DNA unwinding or rewinding. The Pol II elongation complex thus adopts a stable architecture suitable for processive transcription. Science , this issue p. 921 ; see also p. 871