+Search query
-Structure paper
Title | Structural basis of nucleosome transcription mediated by Chd1 and FACT. |
---|---|
Journal, issue, pages | Nat Struct Mol Biol, Vol. 28, Issue 4, Page 382-387, Year 2021 |
Publish date | Apr 12, 2021 |
Authors | Lucas Farnung / Moritz Ochmann / Maik Engeholm / Patrick Cramer / |
PubMed Abstract | Efficient transcription of RNA polymerase II (Pol II) through nucleosomes requires the help of various factors. Here we show biochemically that Pol II transcription through a nucleosome is ...Efficient transcription of RNA polymerase II (Pol II) through nucleosomes requires the help of various factors. Here we show biochemically that Pol II transcription through a nucleosome is facilitated by the chromatin remodeler Chd1 and the histone chaperone FACT when the elongation factors Spt4/5 and TFIIS are present. We report cryo-EM structures of transcribing Saccharomyces cerevisiae Pol II-Spt4/5-nucleosome complexes with bound Chd1 or FACT. In the first structure, Pol II transcription exposes the proximal histone H2A-H2B dimer that is bound by Spt5. Pol II has also released the inhibitory DNA-binding region of Chd1 that is poised to pump DNA toward Pol II. In the second structure, Pol II has generated a partially unraveled nucleosome that binds FACT, which excludes Chd1 and Spt5. These results suggest that Pol II progression through a nucleosome activates Chd1, enables FACT binding and eventually triggers transfer of FACT together with histones to upstream DNA. |
External links | Nat Struct Mol Biol / PubMed:33846633 / PubMed Central |
Methods | EM (single particle) |
Resolution | 2.7 - 3.5 Å |
Structure data | EMDB-12449, PDB-7nkx: EMDB-12450, PDB-7nky: EMDB-12666: EMDB-12667: EMDB-12668: EMDB-12669: EMDB-12670: EMDB-12671: |
Chemicals | ChemComp-ZN: ChemComp-MG: ChemComp-ADP: ChemComp-BEF: |
Source |
|
Keywords | TRANSCRIPTION / chromatin remodelling / nucleosome / chromatin / elongation / histone chaperone |