EMD-12971
Structure of active transcription elongation complex Pol II-DSIF-ELL2-EAF1, Map 9, Global map used to fit SPT4-SPT5-NGN
EMD-12971
Single-particle3.5 Å
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Map released: 14/07/2021
Last modified: 01/09/2021
Sample Organism:
Sus scrofa,
Homo sapiens,
HIV whole-genome vector AA1305#18
Sample: Transcription elongation complex of RNA polymerase II with elongation factors DSIF, ELL2 and EAF1
Deposition Authors: Chen Y, Vos SM, Dienemann C, Ninov M, Urlaub H, Cramer P
Sample: Transcription elongation complex of RNA polymerase II with elongation factors DSIF, ELL2 and EAF1
Deposition Authors: Chen Y, Vos SM, Dienemann C, Ninov M, Urlaub H, Cramer P
Allosteric transcription stimulation by RNA polymerase II super elongation complex.
Abstract:
The super elongation complex (SEC) contains the positive transcription elongation factor b (P-TEFb) and the subcomplex ELL2-EAF1, which stimulates RNA polymerase II (RNA Pol II) elongation. Here, we report the cryoelectron microscopy (cryo-EM) structure of ELL2-EAF1 bound to a RNA Pol II elongation complex at 2.8 Å resolution. The ELL2-EAF1 dimerization module directly binds the RNA Pol II lobe domain, explaining how SEC delivers P-TEFb to RNA Pol II. The same site on the lobe also binds the initiation factor TFIIF, consistent with SEC binding only after the transition from transcription initiation to elongation. Structure-guided functional analysis shows that the stimulation of RNA elongation requires the dimerization module and the ELL2 linker that tethers the module to the RNA Pol II protrusion. Our results show that SEC stimulates elongation allosterically and indicate that this stimulation involves stabilization of a closed conformation of the RNA Pol II active center cleft.
The super elongation complex (SEC) contains the positive transcription elongation factor b (P-TEFb) and the subcomplex ELL2-EAF1, which stimulates RNA polymerase II (RNA Pol II) elongation. Here, we report the cryoelectron microscopy (cryo-EM) structure of ELL2-EAF1 bound to a RNA Pol II elongation complex at 2.8 Å resolution. The ELL2-EAF1 dimerization module directly binds the RNA Pol II lobe domain, explaining how SEC delivers P-TEFb to RNA Pol II. The same site on the lobe also binds the initiation factor TFIIF, consistent with SEC binding only after the transition from transcription initiation to elongation. Structure-guided functional analysis shows that the stimulation of RNA elongation requires the dimerization module and the ELL2 linker that tethers the module to the RNA Pol II protrusion. Our results show that SEC stimulates elongation allosterically and indicate that this stimulation involves stabilization of a closed conformation of the RNA Pol II active center cleft.