8ZK1: BTN2A1-BTN3A1-BTN3A2 mutant complex

Cryo-EM structure of BTN2A1-BTN3A1-BTN3A2 mutant complex (BTN3A1 H381R, BTN2A1 R477A/T510A). Determined by electron microscopy at 3.8 Å resolution. Released 26 Nov 2025.

Method: Electron microscopy
Resolution: 3.8 Å
Organism: Homo sapiens
Chains: 4
Atoms: 6,619
Mol. weight: 218.35 kDa
Released: 26 Nov 2025

Explore 8ZK1 in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

8ZK1 contains 18 α-helices and 91 β-strands across 4 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, 22 β-strands

Element	Residues	Length	Sheet
β-strand	31-33	3	1
α-helix	38	1
β-strand	39-41	3	2
β-strand	47-51	5	3
β-strand	52-54	3	1
β-strand	63-67	5	2
β-strand	76-79	4	2
β-strand	82-84	3	2
β-strand	96-99	4	3
β-strand	108-112	5	3
α-helix	117-119	3
β-strand	121-129	9	2
β-strand	132-142	11	2
β-strand	144	1	4
α-helix	147-149	3
β-strand	150-151	2	5
β-strand	156-157	2	6
β-strand	160-161	2	6
β-strand	164-170	7	5
β-strand	171	1	4
β-strand	174-179	6	7
α-helix	186-188	3
β-strand	190-195	6	5
β-strand	201-206	6	5
β-strand	216-223	8	7
β-strand	228-235	8	7
α-helix	238-240	3

Chain B: 5 helices, 25 β-strands

Element	Residues	Length	Sheet
β-strand	32-33	2	8
α-helix	38	1
β-strand	39	1	9
α-helix	40	1
β-strand	47-53	7	8
β-strand	63-67	5	10
β-strand	74	1	11
β-strand	76-79	4	10
β-strand	82-83	2	10
β-strand	88	1	11
β-strand	96-99	4	8
β-strand	107-112	6	8
β-strand	121-123	3	9
β-strand	124-129	6	10
β-strand	132-135	4	10
β-strand	138-140	3	9
β-strand	144	1	12
α-helix	147-149	3
β-strand	150-153	4	13
β-strand	161-170	10	13
β-strand	171	1	12
α-helix	173-174	2
β-strand	175-179	5	14
β-strand	185-186	2	14
α-helix	187-188	2
β-strand	190-192	3	13
β-strand	201-209	9	13
β-strand	216-223	8	14
β-strand	228-230	3	14
β-strand	233-235	3	14

Chain E: 4 helices, 21 β-strands

Element	Residues	Length	Sheet
β-strand	33-34	2	15
α-helix	39	1
β-strand	40-43	4	16
β-strand	48-54	7	15
β-strand	64-69	6	16
β-strand	75-80	6	16
β-strand	83-84	2	16
β-strand	97-100	4	15
α-helix	104-106	3
β-strand	108-113	6	15
β-strand	122-129	8	16
β-strand	134-144	11	16
β-strand	145	1	17
β-strand	151-156	6	18
β-strand	162-171	10	18
β-strand	172	1	17
α-helix	174-175	2
β-strand	176-177	2	19
β-strand	180-181	2	19
β-strand	186	1	19
β-strand	190-191	2	18
α-helix	192-194	3
β-strand	202-210	9	18
β-strand	218-223	6	19
β-strand	230-236	7	19

Chain F: 4 helices, 23 β-strands

Element	Residues	Length	Sheet
β-strand	33-34	2	20
β-strand	40-43	4	21
β-strand	48-54	7	20
β-strand	64-69	6	21
β-strand	74-80	7	21
β-strand	83	1	21
α-helix	91-93	3
β-strand	97-103	7	20
β-strand	108-113	6	20
β-strand	122-130	9	21
β-strand	133-144	12	21
β-strand	145	1	22
α-helix	148-150	3
β-strand	151-153	3	19
β-strand	162-171	10	19
β-strand	172	1	22
β-strand	176-181	6	18
β-strand	186	1	18
β-strand	190-191	2	19
α-helix	192-194	3
β-strand	195	1	23
β-strand	202	1	19
β-strand	203	1	23
β-strand	204-210	7	19
β-strand	218-224	7	18
β-strand	229-237	9	18
α-helix	239-241	3

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Butyrophilin subfamily 2 member A1	A, B	protein	534	Homo sapiens	Q7KYR7 (AlphaFold model)
Butyrophilin subfamily 3 member A2	E	protein	340	Homo sapiens	P78410 (AlphaFold model)
Butyrophilin subfamily 3 member A1	F	protein	539	Homo sapiens	O00481 (AlphaFold model)

Sequence of entity 1 (A, B), FASTA

>8ZK1_1 Butyrophilin subfamily 2 member A1 (chains A, B)
MDMRVPAQLLGLLLLWLSGARCQFIVVGPTDPILATVGENTTLRCHLSPEKNAEDMEVRW
FRSQFSPAVFVYKGGRERTEEQMEEYRGRTTFVSKDISRGSVALVIHNITAQENGTYRCY
FQEGRSYDEAILHLVVAGLGSKPLISMRGHEDGGIRLECISRGWYPKPLTVWRDPYGGVA
PALKEVSMPDADGLFMVTTAVIIRDKSVRNMSCSINNTLLGQKKESVIFIPESFMPSVSP
CAVALPIIVVILMIPIAVCIYWINKLQKEKKILSGEKEFERETREIALKELEKERVQKEE
ELQVKEKLQEELRWRRTFLHAVDVVLDPDTAHPDLFLSEDRRSVRRCPFRHLGESVPDNP
ERFDSQPCVLGRESFASGKHYWEVEVENVIEWTVGVCRDSVERKGEVLLIPQNGFWTLEM
HKGQYRAVSSPDRILPLKESLCRVGVFLDYEAGDVSFYNMRDRSHIYTCPASAFSVPVRP
FFRLGCEDSPIFICPALTGANGVAVPEEGLTLHRVGTHQSLGSSGMDYKDDDDK

Sequence of entity 2 (E), FASTA

>8ZK1_2 Butyrophilin subfamily 3 member A2 (chains E)
MDMRVPAQLLGLLLLWLSGARCQFSVLGPSGPILAMVGEDADLPCHLFPTMSAETMELKW
VSSSLRQVVNVYADGKEVEDRQSAPYRGRTSILRDGITAGKAALRIHNVTASDSGKYLCY
FQDGDFYEKALVELKVAALGSNLHVEVKGYEDGGIHLECRSTGWYPQPQIQWSNAKGENI
PAVEAPVVADGVGLYEVAASVIMRGGSGEGVSCIIRNSLLGLEKTASISIADPFFRSAQP
WIAALAGTLPILLLLLAGASYFLWRQQKEITALSSEIESEQEMKEMGYAATEREISLRES
LQEELKRKKIQYLTRGEESSSDTNKSAGSSGMDYKDDDDK

Sequence of entity 3 (F), FASTA

>8ZK1_3 Butyrophilin subfamily 3 member A1 (chains F)
MDMRVPAQLLGLLLLWLSGARCQFSVLGPSGPILAMVGEDADLPCHLFPTMSAETMELKW
VSSSLRQVVNVYADGKEVEDRQSAPYRGRTSILRDGITAGKAALRIHNVTASDSGKYLCY
FQDGDFYEKALVELKVAALGSDLHVDVKGYKDGGIHLECRSTGWYPQPQIQWSNNKGENI
PTVEAPVVADGVGLYAVAASVIMRGSSGEGVSCTIRSSLLGLEKTASISIADPFFRSAQR
WIAALAGTLPVLLLLLGGAGYFLWQQQEEKKTQFRKKKREQELREMAWSTMKQEQSTRVK
LLEELRWRSIQYASRGERHSAYNEWKKALFKPADVILDPKTANPILLVSEDQRSVQRAKE
PQDLPDNPERFNWAYCVLGCESFISGRHYWEVEVGDRKEWHIGVCSKNVQRKGWVKMTPE
NGFWTMGLTDGNKYRTLTEPRTNLKLPKPPKKVGVFLDYETGDISFYNAVDGSHIHTFLD
VSFSEALYPVFRILTLEPTALTICPAGSSGAWSHPQFEKGGGSGGGSGGSAWSHPQFEK

Primary citation

Phosphoantigen-driven dissociation of butyrophilin oligomers activates gamma delta T cells. Xin, W., Huang, B., Gao, W. et al. Cell Discov (2026) 12. DOI 10.1038/s41421-026-00911-7 · PubMed

Other PDB entries of the same protein (UniProt Q7KYR7 (AlphaFold model), which also has an AlphaFold model), best resolution first:

8IGT 1.56 Å, Crystal Structure of Intracellular B30.2 Domain of BTN2A1
8DFW 2.1 Å, Crystal Structure of Human BTN2A1 in Complex With Vgamma9-Vdelta2 T Cell Receptor
8JYE 2.18 Å, Crystal Structure of Intracellular B30.2 Domain of BTN3A1 and BTN2A1 in Complex with HMBPP
8JYC 2.29 Å, Crystal Structure of Intracellular B30.2 Domain of BTN3A1 and BTN2A1 in Complex with DMAPP
8VC7 2.76 Å, Crystal Structure of Human BTN2A1 ectodomain in complex with Antagonist 2A1.9 Fab
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
9II6 3.27 Å, Cryo-EM structure of the intracellular domains of BTN2A1-BTN3A1-BTN3A3
9JQ6 3.34 Å, Cryo-EM structure of BTN2A1 in complex with antagonist antibody TH002
9JQP 3.34 Å, Cryo-EM structure of the HMBPP-primed BTN3A1-BTN3A2-BTN2A1 in complex with agonist…

Browse structure collections

About this viewer

MolViewer shows 8ZK1 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.