9CG9: HMGB1 box

Cryo-EM structure of an HMGB1 box bound to nucleosome at SHL-2. Determined by electron microscopy at 2.94 Å resolution. Released 2 Jul 2025.

Method: Electron microscopy
Resolution: 2.94 Å
Organisms: Xenopus laevis, synthetic construct, Homo sapiens
Chains: 11
Atoms: 12,706
Mol. weight: 228.24 kDa
Released: 2 Jul 2025

Explore 9CG9 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9CG9 contains 43 α-helices and 20 β-strands across 9 chains. Residue ranges use author residue numbering, as in the PDB file, from PDBe. To see them in 3D, choose the Cartoon representation with Secondary structure coloring: helices, sheets and coils get different colors.

Chain A: 5 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	41-42	2
α-helix	45-56	12
α-helix	64-75	12
β-strand	83-84	2	1
α-helix	86-113	28
β-strand	118-119	2	2
α-helix	121-130	10

Chain B: 4 helices, 3 β-strands

Element	Residues	Length	Sheet
α-helix	26-28	3
α-helix	31-40	10
β-strand	45-46	2	2
α-helix	50-75	26
β-strand	80-81	2	1
α-helix	83-92	10
β-strand	96-98	3	3

Chain C: 6 helices, 3 β-strands

Element	Residues	Length	Sheet
α-helix	17-21	5
α-helix	27-36	10
β-strand	42-43	2	4
α-helix	46-72	27
β-strand	77-78	2	5
α-helix	80-89	10
α-helix	91-96	6
β-strand	101-102	2	6
α-helix	113-115	3

Chain D: 4 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	38-48	11
β-strand	53-54	2	5
α-helix	56-83	28
β-strand	88-89	2	4
α-helix	91-101	11
α-helix	104-124	21

Chain E: 5 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	41-42	2
α-helix	45-56	12
α-helix	64-76	13
β-strand	83-84	2	7
α-helix	86-113	28
β-strand	118-119	2	8
α-helix	121-130	10

Chain F: 4 helices, 3 β-strands

Element	Residues	Length	Sheet
α-helix	25-28	4
α-helix	31-40	10
β-strand	45-46	2	8
α-helix	50-75	26
β-strand	80-81	2	7
α-helix	83-92	10
β-strand	97-98	2	6

Chain G: 7 helices, 3 β-strands

Element	Residues	Length	Sheet
α-helix	12-14	3
α-helix	17-21	5
α-helix	27-36	10
β-strand	42-43	2	9
α-helix	46-72	27
β-strand	77-78	2	10
α-helix	80-89	10
α-helix	93-96	4
β-strand	100-102	3	3
α-helix	113-115	3

Chain H: 4 helices, 2 β-strands

Element	Residues	Length	Sheet
α-helix	38-48	11
β-strand	53-54	2	10
α-helix	56-83	28
β-strand	88-89	2	9
α-helix	91-101	11
α-helix	104-122	19

1 more chain groups are not listed. Open the entry in the viewer and use the sequence panel to see them.

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Histone H3.2	A, E	protein	135	Xenopus laevis	P84233 (AlphaFold model)
Histone H4	B, F	protein	102	Xenopus laevis	P62799 (AlphaFold model)
Histone H2A type 1	C, G	protein	129	Xenopus laevis	P06897 (AlphaFold model)
Histone H2B	D, H	protein	122	Xenopus laevis	P02281 (AlphaFold model)
Widom 601 DNA reverse strand (147-mer)	I	DNA	154	synthetic construct
Widom 601 DNA forward strand (147-mer)	J	DNA	154	synthetic construct
High mobility group protein B1	K	protein	217	Homo sapiens	P09429

Sequence of entity 1 (A, E), FASTA

>9CG9_1 Histone H3.2 (chains A, E)
ARTKQTARKSTGGKAPRKQLATKAARKSAPATGGVKKPHRYRPGTVALREIRRYQKSTEL
LIRKLPFQRLVREIAQDFKTDLRFQSSAVMALQEASEAYLVALFEDTNLAAIHAKRVTIM
PKDIQLARRIRGERA

Sequence of entity 2 (B, F), FASTA

>9CG9_2 Histone H4 (chains B, F)
SGRGKGGKGLGKGGAKRHRKVLRDNIQGITKPAIRRLARRGGVKRISGLIYEETRGVLKV
FLENVIRDAVTYTEHAKRKTVTAMDVVYALKRQGRTLYGFGG

Sequence of entity 3 (C, G), FASTA

>9CG9_3 Histone H2A type 1 (chains C, G)
SGRGKQGGKTRAKAKTRSSRAGLQFPVGRVHRLLRKGNYAERVGAGAPVYLAAVLEYLTA
EILELAGNAARDNKKTRIIPRHLQLAVRNDEELNKLLGRVTIAQGGVLPNIQSVLLPKKT
ESSKSAKSK

Sequence of entity 4 (D, H), FASTA

>9CG9_4 Histone H2B (chains D, H)
AKSAPAPKKGSKKAVTKTQKKDGKKRRKTRKESYAIYVYKVLKQVHPDTGISSKAMSIMN
SFVNDVFERIAGEASRLAHYNKRSTITSREIQTAVRLLLPGELAKHAVSEGTKAVTKYTS
AK

Sequence of entity 5 (I), FASTA

>9CG9_5 Widom 601 DNA reverse strand (147-mer) (chains I)
TACATGCACAGGATGTATATATCTGACACGTGCCTGGAGACTAGGGAGTAATCCCCTTGG
CGGTTAAAACGCGGGGGACAGCGCGTACGTGCGTTTAAGCGGTGCTAGAGCTGTCTACGA
CCAATTGAGCGGCCTCGGCACCGGGATTCTCCAG

Sequence of entity 6 (J), FASTA

>9CG9_6 Widom 601 DNA forward strand (147-mer) (chains J)
CTGGAGAATCCCGGTGCCGAGGCCGCTCAATTGGTCGTAGACAGCTCTAGCACCGCTTAA
ACGCACGTACGCGCTGTCCCCCGCGTTTTAACCGCCAAGGGGATTACTCCCTAGTCTCCA
GGCACGTGTCAGATATATACATCCTGTGCATGTA

Sequence of entity 7 (K), FASTA

>9CG9_7 High mobility group protein B1 (chains K)
GSMGKGDPKKPRGKMSSYAFFVQTCREEHKKKHPDASVNFSEFSKKCSERWKTMSAKEKG
KFEDMAKADKARYEREMKTYIPPKGETKKKFKDPNAPKRPPSAFFLFCSEYRPKIKGEHP
GLSIGDVAKKLGEMWNNTAADDKQPYEKKAAKLKEKYEKDIAAYRAKGKPDAAKKGVVKA
EKSKKKKEEEEDEEDEEDEEEEEDEEDEDEEEDDDDE

Primary citation

HMGB1 deforms nucleosomal DNA to generate a dynamic chromatin environment counteracting the effects of linker histone. Saunders, H.S., Chio, U.S., Moore, C.M. et al. Sci Adv (2025) 11:eads4473-eads4473. DOI 10.1126/sciadv.ads4473 · PubMed

Other PDB entries of the same protein (UniProt P84233 (AlphaFold model), which also has an AlphaFold model), best resolution first:

2HUE 1.7 Å, Structure of the H3-H4 chaperone Asf1 bound to histones H3 and H4
3GV6 1.76 Å, Crystal Structure of human chromobox homolog 6 (CBX6) with H3K9 peptide
1KX5 1.94 Å, X-Ray Structure of the Nucleosome Core Particle, NCP147, at 1.9 A Resolution
1KX3 2.0 Å, X-Ray Structure of the Nucleosome Core Particle, NCP146, at 2.0 A Resolution
4QEO 2.0 Å, crystal structure of KRYPTONITE in complex with mCHH DNA, H3(1-15) peptide and SAH
1S32 2.05 Å, Molecular Recognition of the Nucleosomal 'Supergroove'
3UTA 2.07 Å, Crystal Structure of Nucleosome Core Particle Assembled with an Alpha-Satellite Sequence…
3C1B 2.2 Å, The effect of H3 K79 dimethylation and H4 K20 trimethylation on nucleosome and chromatin…
3UT9 2.2 Å, Crystal Structure of Nucleosome Core Particle Assembled with a Palindromic Widom '601'…
3UTB 2.2 Å, Crystal Structure of Nucleosome Core Particle Assembled with the 146b Alpha-Satellite…
6WZ5 2.2 Å, Bridging of double-strand DNA break activates PARP2/HPF1 to modify chromatin
8RUQ 2.29 Å, Borealin N-terminus in complex with H3.T3p-nucleosome

Browse structure collections

About this viewer

MolViewer shows 9CG9 directly in your browser with nothing to install. Switch between cartoon, ball-and-stick, spacefill and surface views, color by chain, secondary structure or B-factor, measure distances, angles and dihedrals, and share or embed the view.