7NKY

RNA Polymerase II-Spt4/5-nucleosome-FACT structure

Summary for 7NKY

• Entry DOI: 10.2210/pdb7nky/pdb
• EMDB information: 12450
• Descriptor: RNA (5'-R(P*UP*CP*UP*UP*UP*UP*AP*UP*UP*UP*UP*UP*UP*CP*UP*G)-3'), DNA-directed RNA polymerase II subunit RPB9, DNA-directed RNA polymerases I, II, and III subunit RPABC5, ... (25 entities in total)
• Functional Keywords: chromatin, nucleosome, elongation, histone chaperone, transcription
• Biological source: Saccharomyces cerevisiae (Baker's yeast); More
• Total number of polymer chains: 27
• Total formula weight: 1026147.66

Authors

Farnung, L.,Ochmann, M.,Engeholm, M.,Cramer, P. (deposition date: 2021-02-19, release date: 2021-07-07, Last modification date: 2024-07-10)

Primary citation

Farnung, L.,Ochmann, M.,Engeholm, M.,Cramer, P.
Structural basis of nucleosome transcription mediated by Chd1 and FACT.
Nat.Struct.Mol.Biol., 28:382-387, 2021

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 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.

PubMed: 33846633
DOI: 10.1038/s41594-021-00578-6

Experimental method

ELECTRON MICROSCOPY (3.2 Å)