9L1O: ICT01-BTN3A1/BTN3A2 complex, local refinement

Cryo-EM structure of the ICT01-BTN3A1/BTN3A2 complex, local refinement. Determined by electron microscopy at 3.7 Å resolution. Released 17 Dec 2025.

Method: Electron microscopy
Resolution: 3.7 Å
Organism: Homo sapiens
Chains: 3
Atoms: 4,253
Mol. weight: 90.93 kDa
Released: 17 Dec 2025

Explore 9L1O in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

9L1O contains 12 α-helices and 56 β-strands across 3 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 E: 1 helix, 16 β-strands

Element	Residues	Length	Sheet
β-strand	33-34	2	1
β-strand	40-41	2	2
β-strand	43	1	3
β-strand	46	1	3
β-strand	48-54	7	1
β-strand	64-68	5	4
β-strand	69	1	5
β-strand	75-80	6	4
β-strand	83-85	3	4
β-strand	98-101	4	1
α-helix	104-106	3
β-strand	108-113	6	1
β-strand	122-123	2	2
β-strand	124	1	5
β-strand	127-129	3	4
β-strand	134-136	3	4
β-strand	140-142	3	2

Chain H: 5 helices, 19 β-strands

Element	Residues	Length	Sheet
β-strand	3-6	4	6
α-helix	7-9	3
β-strand	10-12	3	7
β-strand	16-25	10	6
β-strand	34-39	6	7
β-strand	45-51	7	7
α-helix	63-65	3
β-strand	68-73	6	6
β-strand	78-86	9	6
α-helix	88-90	3
β-strand	92-99	8	7
β-strand	109-112	4	7
α-helix	114-115	2
β-strand	116-120	5	7
β-strand	126	1	8
β-strand	129-133	5	9
β-strand	145-154	10	9
β-strand	155	1	8
β-strand	161-163	3	10
β-strand	172-174	3	9
β-strand	185-193	9	9
β-strand	204-209	6	10
α-helix	210-212	3
β-strand	214-219	6	10

Chain L: 6 helices, 21 β-strands

Element	Residues	Length	Sheet
β-strand	5-7	3	11
β-strand	10-12	3	12
β-strand	19-24	6	11
β-strand	33-38	6	12
α-helix	43-44	2
β-strand	45-46	2	12
β-strand	48-49	2	13
β-strand	53-54	2	13
α-helix	55	1
β-strand	62-65	4	11
β-strand	70-75	6	11
β-strand	85-90	6	12
β-strand	98	1	12
β-strand	103-105	3	12
β-strand	114-118	5	14
α-helix	119	1
β-strand	120	1	9
α-helix	121	1
α-helix	122-127	6
β-strand	129-139	11	14
β-strand	145-150	6	15
β-strand	153-155	3	15
β-strand	162-163	2	14
β-strand	173-182	10	14
α-helix	183-186	4
β-strand	191-197	7	15
β-strand	206-210	5	15

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Butyrophilin subfamily 3 member A2	E	protein	340	Homo sapiens	P78410 (AlphaFold model)
ICT01 heavy chain	H	protein	255	Homo sapiens
ICT01 light chain	L	protein	236	Homo sapiens

Sequence of entity 1 (E), FASTA

>9L1O_1 Butyrophilin subfamily 3 member A2 (chains E)
MDMRVPAQLLGLLLLWLSGARCQFSVLGPSGPILAMVGEDADLPCHLFPTMSAETMELKW
VSSSLRQVVNVYADGKEVEDRQSAPYRGRTSILRDGITAGKAALRIHNVTASDSGKYLCY
FQDGDFYEKALVELKVAALGSNLHVEVKGYEDGGIHLECRSTGWYPQPQIQWSNAKGENI
PAVEAPVVADGVGLYEVAASVIMRGGSGEGVSCIIRNSLLGLEKTASISIADPFFRSAQP
WIAALAGTLPILLLLLAGASYFLWRQQKEITALSSEIESEQEMKEMGYAATEREISLRES
LQEELKRKKIQYLTRGEESSSDTNKSAGSSGMDYKDDDDK

Sequence of entity 2 (H), FASTA

>9L1O_2 ICT01 heavy chain (chains H)
MEFGLSWLFLVAILKGVQCQVQLVQSGAEVKKPGASVKLSCKASGYIFTRYYMYWVKQRP
GQGLEWIGEINPNNGGTKFNEKFKNRATLTVDKSISTAYMELSRLRSDDTAVYYCSREDD
YDGTPFAMDYWGQGTLVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTV
SWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVE
PKSCGGSHHHHHHHH

Sequence of entity 3 (L), FASTA

>9L1O_3 ICT01 light chain (chains L)
MDMRVPAQLLGLLLLWLSGARCDIQMTQSPSSLSASVGDRVTITCHASQNINVWLSWYQQ
KPGKAPKLLIYKASNLHTGVPSRFSGSGSGTDFTFTISSLQPEDIATYYCQQGQTYPYTF
GQGTKLEIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGN
SQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC

Primary citation

local refinement of the ICT01-BTN3A1/BTN3A2 complex at 3.7 Angstroms resolution. Xin, W.Z., Huang, B.D., Zhou, Q. To be published.

Other PDB entries of the same protein (UniProt P78410 (AlphaFold model), which also has an AlphaFold model), best resolution first:

4F8Q 2.38 Å, Crystal Structure of the Human BTN3A2 Ectodomain
8ZHR 3.0 Å, Cryo-EM structure of the full-length pAg-bound BTN2A1-BTN3A1-BTN3A2 complex
9JQR 3.0 Å, Cryo-EM structure of the Vgamma9Vdelta2 TCR-engaged BTN3A1-BTN3A2-BTN2A1 complex
9IRD 3.2 Å, Cryo-EM structure of BTN2A1-BTN3A1-BTN3A2 mutant (BTN3A1 H381R, BTN2A1 R477A/T510A) in…
9JQQ 3.26 Å, Cryo-EM structure of the HMBPP-primed BTN3A1-BTN3A2-BTN2A1 complex
9JQP 3.34 Å, Cryo-EM structure of the HMBPP-primed BTN3A1-BTN3A2-BTN2A1 in complex with agonist…
8ZJX 3.35 Å, Cryo-EM structure of the full length pAg-bound BTN2A1-BTN3A1-BTN3A2 in complex with…
8ZK0 3.4 Å, Cryo-EM structure of the full length pAg-bound BTN2A1-BTN3A1-BTN3A2 in complex with…
9L1P 3.5 Å, Cryo-EM structure of the ICT01-BTN2A1/BTN3A1/BTN3A2 complex, local refinement
9KWE 3.7 Å, Cryo-EM structure of the ICT01-BTN3A1/BTN3A2 complex
9KWZ 3.7 Å, Cryo-EM structure of the ICT01-BTN2A1/BTN3A1/BTN3A2 complex
8ZK1 3.8 Å, Cryo-EM structure of BTN2A1-BTN3A1-BTN3A2 mutant complex (BTN3A1 H381R, BTN2A1…

Browse structure collections

About this viewer

MolViewer shows 9L1O 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.