Biological Assembly 1  

 3D View: Structure

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 10-mer - A2B2C2D2E1F1 Pseudo Symmetry: Asymmetric - C1 
Pseudo Stoichiometry: Hetero 10-mer - A7B1C1D1 

Biological assembly 1 assigned by authors.

Biological Assembly Evidence: native gel electrophoresis

Macromolecule Content

• Total Structure Weight: 341.47 kDa 
• Atom Count: 15882 
• Residue Count: 1747 
• Unique protein chains: 6
• Unique nucleic acid chains: 2

6UPL

Structure of FACT_subnucleosome complex 2

• DOI: 10.2210/pdb6UPL/pdb
• EMDataResource: EMD-20841

• Classification: TRANSCRIPTION/DNA
• Organism(s): Homo sapiens, Escherichia coli
• Expression System: Escherichia coli 'BL21-Gold(DE3)pLysS AG, Spodoptera frugiperda
• Mutation(s): No 


• Deposited: 2019-10-17 Released: 2019-12-11 
• Deposition Author(s): Zhou, K., Tan, Y.Z., Wei, H., Liu, Y., Carragher, B., Potter, C., Luger, K.
• Funding Organization(s): Howard Hughes Medical Institute (HHMI)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 7.40 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

FACT caught in the act of manipulating the nucleosome.

Liu, Y., Zhou, K., Zhang, N., Wei, H., Tan, Y.Z., Zhang, Z., Carragher, B., Potter, C.S., D'Arcy, S., Luger, K.

(2020) Nature 577: 426-431

• PubMed: 31775157 
• DOI: 10.1038/s41586-019-1820-0
• Primary Citation of Related Structures:  
  6UPL, 6UPK


• PubMed Abstract: 
  

The organization of genomic DNA into nucleosomes profoundly affects all DNA-related processes in eukaryotes. The histone chaperone known as 'facilitates chromatin transcription' (FACT ¹ ) (consisting of subunits SPT16 and SSRP1) promotes both disassembly and reassembly of nucleosomes during gene transcription, DNA replication and DNA repair ² . However, the mechanism by which FACT causes these opposing outcomes is unknown. Here we report two cryo-electron-microscopic structures of human FACT in complex with partially assembled subnucleosomes, with supporting biochemical and hydrogen-deuterium exchange data. We find that FACT is engaged in extensive interactions with nucleosomal DNA and all histone variants. The large DNA-binding surface on FACT appears to be protected by the carboxy-terminal domains of both of its subunits, and this inhibition is released by interaction with H2A-H2B, allowing FACT-H2A-H2B to dock onto a complex containing DNA and histones H3 and H4 (ref. ³ ). SPT16 binds nucleosomal DNA and tethers H2A-H2B through its carboxy-terminal domain by acting as a placeholder for DNA. SSRP1 also contributes to DNA binding, and can assume two conformations, depending on whether a second H2A-H2B dimer is present. Our data suggest a compelling mechanism for how FACT maintains chromatin integrity during polymerase passage, by facilitating removal of the H2A-H2B dimer, stabilizing intermediate subnucleosomal states and promoting nucleosome reassembly. Our findings reconcile discrepancies regarding the many roles of FACT and underscore the dynamic interactions between histone chaperones and nucleosomes.

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Organizational Affiliation: 

Howard Hughes Medical Institute, Chevy Chase, MD, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H3.1	A, E	136	Homo sapiens	Mutation(s): 0  Gene Names:  H3C1, H3FA, HIST1H3A, H3C2, H3FL, HIST1H3B, H3C3, H3FC HIST1H3C, H3C4, H3FB, HIST1H3D, H3C6, H3FD, HIST1H3E, H3C7, H3FI, HIST1H3F, H3C8, H3FH, HIST1H3G, H3C10, H3FK, HIST1H3H, H3C11, H3FF, HIST1H3I, H3C12, H3FJ, HIST1H3J
Find proteins for P68431 (Homo sapiens) Explore P68431  Go to UniProtKB:  P68431
NIH Common Fund Data Resources
PHAROS  P68431 GTEx  ENSG00000197409GTEx  ENSG00000197153GTEx  ENSG00000278828GTEx  ENSG00000275714GTEx  ENSG00000273983GTEx  ENSG00000274750GTEx  ENSG00000275379GTEx  ENSG00000277775

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H4	B, F	103	Homo sapiens	Mutation(s): 0  Gene Names:  HIST1H4A, H4/A, H4FA, HIST1H4B, H4/I, H4FI, HIST1H4C, H4/G, H4FG, HIST1H4D, H4/B, H4FB, HIST1H4E, H4/J, H4FJ, HIST1H4F, H4/C, H4FC, HIST1H4H, H4/H, H4FH, HIST1H4I, H4/M, H4FM, HIST1H4J, H4/E, H4FE, HIST1H4K, H4/D, H4FD, HIST1H4L, H4/K, H4FK, HIST2H4A, H4/N, H4F2, H4FN, HIST2H4, HIST2H4B, H4/O, H4FO, HIST4H4, H4C1, H4C2, H4C3, H4C4, H4C5, H4C6, H4C8, H4C9, H4C11, H4C12, H4C13, H4C14, H4C15, H4-16
Find proteins for P62805 (Homo sapiens) Explore P62805  Go to UniProtKB:  P62805
NIH Common Fund Data Resources
PHAROS  P62805 GTEx  ENSG00000274618GTEx  ENSG00000197238GTEx  ENSG00000197837GTEx  ENSG00000158406GTEx  ENSG00000278705GTEx  ENSG00000197061GTEx  ENSG00000270882GTEx  ENSG00000270276GTEx  ENSG00000273542GTEx  ENSG00000277157GTEx  ENSG00000276966GTEx  ENSG00000276180GTEx  ENSG00000278637GTEx  ENSG00000275126

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H2A	C, K	130	Homo sapiens	Mutation(s): 0  Gene Names: HIST1H2AC, H2AFL, H2AC6
Find proteins for Q93077 (Homo sapiens) Explore Q93077  Go to UniProtKB:  Q93077
NIH Common Fund Data Resources
PHAROS  Q93077 GTEx  ENSG00000180573

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
Histone H2B	D, L	126	Homo sapiens	Mutation(s): 0  Gene Names:  HIST1H2BC, H2BFL, HIST1H2BE, H2BFH, HIST1H2BF, H2BFG, HIST1H2BG, H2BFA, HIST1H2BI, H2BFK, H2BC4, H2BC6, H2BC7, H2BC8, H2BC10
Find proteins for P62807 (Homo sapiens) Explore P62807  Go to UniProtKB:  P62807
NIH Common Fund Data Resources
PHAROS  P62807 GTEx  ENSG00000180596GTEx  ENSG00000277224GTEx  ENSG00000278588GTEx  ENSG00000273802GTEx  ENSG00000274290

Entity ID: 5
Molecule	Chains	Sequence Length	Organism	Details	Image
FACT complex subunit SPT16	G	966	Homo sapiens	Mutation(s): 0  Gene Names: SUPT16H, FACT140, FACTP140
Find proteins for Q9Y5B9 (Homo sapiens) Explore Q9Y5B9  Go to UniProtKB:  Q9Y5B9
NIH Common Fund Data Resources
PHAROS  Q9Y5B9 GTEx  ENSG00000092201

Entity ID: 6
Molecule	Chains	Sequence Length	Organism	Details	Image
FACT complex subunit SSRP1	H	640	Homo sapiens	Mutation(s): 0  Gene Names: SSRP1, FACT80
Find proteins for Q08945 (Homo sapiens) Explore Q08945  Go to UniProtKB:  Q08945
NIH Common Fund Data Resources
PHAROS  Q08945 GTEx  ENSG00000149136

Entity ID: 7
Molecule	Chains	Length	Organism	Image
DNA (79-mer)	I	79	Escherichia coli

Entity ID: 8
Molecule	Chains	Length	Organism	Image
DNA (79-mer)	J	79	Escherichia coli

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 7.40 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2019-10-17 
• Released Date: 2019-12-11 
Deposition Author(s): Zhou, K., Tan, Y.Z., Wei, H., Liu, Y., Carragher, B., Potter, C., Luger, K.

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Funding Organization	Location	Grant Number
Howard Hughes Medical Institute (HHMI)	United States	--

Revision History 

• Version 1.0: 2019-12-11
  Type: Initial release
  
• Version 1.1: 2020-01-15
  Changes: Author supporting evidence
• Version 1.2: 2020-01-29
  Changes: Database references