7LBM

Structure of the human Mediator-bound transcription pre-initiation complex

This is a non-PDB format compatible entry.

Summary for 7LBM

• Entry DOI: 10.2210/pdb7lbm/pdb
• EMDB information: 23255
• Descriptor: Isoform 2 of Mediator of RNA polymerase II transcription subunit 16, DNA-directed RNA polymerases I, II, and III subunit RPABC2, DNA-directed RNA polymerase II subunit RPB7, ... (59 entities in total)
• Functional Keywords: pre-initiation complex, mediator, initiation, complex, transcription, transcription-dna complex, transcription/dna
• Biological source: Homo sapiens (Human); More
• Total number of polymer chains: 56
• Total formula weight: 2509244.44

Authors

Abdella, R.,Talyzina, A.,He, Y. (deposition date: 2021-01-08, release date: 2021-03-24, Last modification date: 2024-10-16)

Primary citation

Abdella, R.,Talyzina, A.,Chen, S.,Inouye, C.J.,Tjian, R.,He, Y.
Structure of the human Mediator-bound transcription preinitiation complex.
Science, 372:52-56, 2021

PubMed Abstract: Eukaryotic transcription requires the assembly of a multisubunit preinitiation complex (PIC) composed of RNA polymerase II (Pol II) and the general transcription factors. The coactivator Mediator is recruited by transcription factors, facilitates the assembly of the PIC, and stimulates phosphorylation of the Pol II C-terminal domain (CTD) by the TFIIH subunit CDK7. Here, we present the cryo-electron microscopy structure of the human Mediator-bound PIC at a resolution below 4 angstroms. Transcription factor binding sites within Mediator are primarily flexibly tethered to the tail module. CDK7 is stabilized by multiple contacts with Mediator. Two binding sites exist for the Pol II CTD, one between the head and middle modules of Mediator and the other in the active site of CDK7, providing structural evidence for Pol II CTD phosphorylation within the Mediator-bound PIC.

PubMed: 33707221
DOI: 10.1126/science.abg3074

Experimental method

ELECTRON MICROSCOPY (4.8 Å)