9XXT: Probable G-protein coupled receptor 174

Cryo-EM structure of lysophosphatidylserine (18:0)-bound GPR174-Gs complex. Determined by electron microscopy at 2.0 Å resolution. Released 15 Apr 2026.

Method: Electron microscopy
Resolution: 2.0 Å
Organisms: Homo sapiens, synthetic construct
Chains: 5
Atoms: 8,333
Mol. weight: 141.98 kDa
Ligands: A1E1Q
Released: 15 Apr 2026

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

Secondary structure: helices and β-sheets

9XXT contains 37 α-helices and 46 β-strands across 5 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: 10 helices, 6 β-strands

Element	Residues	Length	Sheet
α-helix	12-39	28
β-strand	41-46	6	1
β-strand	208-214	7	1
β-strand	217-223	7	1
α-helix	234-238	5
β-strand	243-249	7	1
α-helix	265-277	13
α-helix	280-282	3
β-strand	286-292	7	1
α-helix	294-303	10
α-helix	308-311	4
α-helix	313-317	5
α-helix	326-327	2
α-helix	332-351	20
β-strand	359-363	5	1
α-helix	371-390	20

Chain B: 3 helices, 28 β-strands

Element	Residues	Length	Sheet
α-helix	3-24	22
α-helix	30-33	4
α-helix	38-39	2
β-strand	45-51	7	2
β-strand	58-63	6	3
β-strand	69-74	6	3
β-strand	78-83	6	3
β-strand	88-94	7	3
β-strand	100-105	6	4
β-strand	111-116	6	4
β-strand	121-125	5	4
β-strand	134-139	6	4
β-strand	146-151	6	5
β-strand	156-161	6	5
β-strand	166-170	5	5
β-strand	175-180	6	5
β-strand	187-192	6	6
β-strand	198-203	6	6
β-strand	208-212	5	6
β-strand	217-222	6	6
β-strand	229-234	6	7
β-strand	240-245	6	7
β-strand	250-254	5	7
β-strand	259-264	6	7
β-strand	273-278	6	8
β-strand	284-289	6	8
β-strand	294-298	5	8
β-strand	304-308	5	8
β-strand	315-320	6	2
β-strand	327-331	5	2
β-strand	336-341	6	2

Chain C: 4 helices, 0 β-strands

Element	Residues	Length
α-helix	7-23	17
α-helix	30-43	14
α-helix	53-55	3
α-helix	56-58	3

Chain N: 4 helices, 12 β-strands

Element	Residues	Length	Sheet
β-strand	3-8	6	9
β-strand	10-11	2	10
β-strand	17-25	9	9
α-helix	29-31	3
β-strand	34-39	6	10
β-strand	45-51	7	10
β-strand	58-60	3	10
α-helix	62-64	3
β-strand	68-73	6	9
β-strand	78-84	7	9
α-helix	88-90	3
β-strand	92-98	7	10
β-strand	118	1	10
β-strand	120	1	9
α-helix	121	1
β-strand	122-125	4	10

Chain R: 16 helices, 0 β-strands

Element	Residues	Length
α-helix	21-50	30
α-helix	56-70	15
α-helix	72-81	10
α-helix	88-121	34
α-helix	123-125	3
α-helix	128-131	4
α-helix	134-148	15
α-helix	151-154	4
α-helix	169-171	3
α-helix	179-190	12
α-helix	191-195	5
α-helix	196-211	16
α-helix	224-257	34
α-helix	265-282	18
α-helix	284-292	9
α-helix	297-302	6

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Probable G-protein coupled receptor 174	R	protein	333	Homo sapiens	Q9BXC1 (AlphaFold model)
Isoform Gnas-2 of Guanine nucleotide-binding protein G(s) subunit alpha isoforms short	A	protein	372	Homo sapiens	P63092 (AlphaFold model)
Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1	B	protein	342	Homo sapiens	P62873 (AlphaFold model)
Nanobody35	N	protein	128	synthetic construct
Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2	C	protein	71	Homo sapiens	P59768 (AlphaFold model)

Sequence of entity 1 (R), FASTA

>9XXT_1 Probable G-protein coupled receptor 174 (chains R)
MPANYTCTRPDGDNTDFRYFIYAVTYTVILVPGLIGNILALWVFYGYMKETKRAVIFMIN
LAIADLLQVLSLPLRIFYYLNHDWPFGPGLCMFCFYLKYVNMYASIYFLVCISVRRFWFL
MYPFRFHDCKQKYDLYISIAGWLIICLACVLFPLLRTSDDTSGNRTKCFVDLPTRNVNLA
QSVVMMTIGELIGFVTPLLIVLYCTWKTVLSLQDKYPMAQDLGEKQKALKMILTCAGVFL
ICFAPYHFSFPLDFLVKSNEIKSCLARRVILIFHSVALCLASLNSCLDPVIYYFSTNEFR
RRLSRQDLHDSIQLHAKSFVSNHTASTMTPELC

Sequence of entity 2 (A), FASTA

>9XXT_2 Isoform Gnas-2 of Guanine nucleotide-binding protein G(s) subunit alpha isoforms short (chains A)
TEDQRNEEKAQREANKMIEKQLQKDKQVYRATHRLLLLGADNSGKSTIVKQMRILHVNGF
NGDSEKATKVQDIKNNLKEAIETIVAAMSNLVPPVELANPENQFRVDYILSVMNVPDFDF
PPEFYEHAKALWEDEGVRACYERSNEYQLIDCAQYFLDKIDVIKQADYVPSDQDLLRCRV
LTSGIFETKFQVDKVNFHMFDVGAQRDERRKWIQCFNDVTAIIFVVDSSDYNMVIREDNQ
TNRLQEALNDFKSIWNNRWLRTISVILFLNKQDLLAEKVLAGKSKIEDYFPEFARYTTPE
DATPEPGEDPRVTRAKYFIRDEFLRISTASGDGRHYCYPHFTCSVDTENARRIFNDCRDI
IQRMHLRQYELL

Sequence of entity 3 (B), FASTA

>9XXT_3 Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1 (chains B)
SELDQLRQEAEQLKNQIRDARKACADATLSQITNNIDPVGRIQMRTRRTLRGHLAKIYAM
HWGTDSRLLVSASQDGKLIIWDSYTTNKVHAIPLRSSWVMTCAYAPSGNYVACGGLDNIC
SIYNLKTREGNVRVSRELAGHTGYLSCCRFLDDNQIVTSSGDTTCALWDIETGQQTTTFT
GHTGDVMSLSLAPDTRLFVSGACDASAKLWDVREGMCRQTFTGHESDINAICFFPNGNAF
ATGSDDATCRLFDLRADQELMTYSHDNIICGITSVSFSKSGRLLLAGYDDFNCNVWDALK
ADRAGVLAGHDNRVSCLGVTDDGMAVATGSWDSFLKIWNGSS

Sequence of entity 4 (N), FASTA

>9XXT_4 Nanobody35 (chains N)
QVQLQESGGGLVQPGGSLRLSCAASGFTFSNYKMNWVRQAPGKGLEWVSDISQSGASISY
TGSVKGRFTISRDNAKNTLYLQMNSLKPEDTAVYYCARCPAPFTRDCFDVTSTTYAYRGQ
GTQVTVSS

Sequence of entity 5 (C), FASTA

>9XXT_5 Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2 (chains C)
MASNNTASIAQARKLVEQLKMEANIDRIKVSKAAADLMAYCEAHAKEDPLLTPVPASENP
FREKKFFCAIL

Ligands and cofactors

ID	Name	Formula	Copies
A1E1Q	(2~{S})-2-azanyl-3-[[(2~{R})-3-octadecanoyloxy-2-oxidanyl-propoxy]-oxidanyl-pho…	C24 H48 N O9 P	1

Primary citation

Hydration network drives activation and G protein selectivity in GPR174. Dong, Y.-J., Xi, K., Zhang, Y.-Z. et al. To be published.

Other PDB entries of the same protein (UniProt Q9BXC1 (AlphaFold model), which also has an AlphaFold model), best resolution first:

7XV3 2.76 Å, Cryo-EM structure of LPS-bound GPR174 in complex with Gs protein
8KH5 2.83 Å, Cryo-EM structure of the GPR174-Gs complex bound to endogenous lysoPS
8IZB 3.06 Å, Lysophosphatidylserine receptor GPR174-Gs complex
20YC 3.4 Å, Cryo-EM structure of GPR174-Gi complex

Browse structure collections

About this viewer

MolViewer shows 9XXT 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.