8Z8B | pdb_00008z8b

Cryo-EM structure of human HCAR1-Gi complex without ligand (apo state)

• PDB DOI: https://doi.org/10.2210/pdb8Z8B/pdb
• EM Map EMD-39844: EMDB EMDataResource

• Classification: MEMBRANE PROTEIN
• Organism(s): Homo sapiens, synthetic construct
• Expression System: Spodoptera frugiperda, Trichoplusia ni
• Mutation(s): No 


• Deposited: 2024-04-21 Released: 2025-10-29 
• Deposition Author(s): Gao, M., Zang, S., Zhu, Y., Mao, C., Zhang, Y., Ma, X.
• Funding Organization(s): Not funded

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 2.65 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Cryo-EM structure of human HCAR1-Gi complex without ligand (apo state)

Gao, M., Zang, S., Zhu, Y., Mao, C., Zhang, Y., Ma, X.

To be published.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 5-mer - A1B1C1D1E1 

Biological assembly 1 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 152.01 kDa 
• Atom Count: 8,875 
• Modeled Residue Count: 1,137 
• Deposited Residue Count: 1,365 
• Unique protein chains: 5

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Hydroxycarboxylic acid receptor 1	A [auth R]	346	Homo sapiens	Mutation(s): 0  Gene Names: HCAR1, GPR104, GPR81, HCA1, FKSG80
UniProt & NIH Common Fund Data Resources
Find proteins for Q9BXC0 (Homo sapiens) Explore Q9BXC0  Go to UniProtKB:  Q9BXC0
PHAROS:  Q9BXC0 GTEx:  ENSG00000196917

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Guanine nucleotide-binding protein G(i) subunit alpha-1	B [auth A]	354	Homo sapiens	Mutation(s): 0  Gene Names: GNAI1 EC: 3.6.5
UniProt & NIH Common Fund Data Resources
Find proteins for P63096 (Homo sapiens) Explore P63096  Go to UniProtKB:  P63096
PHAROS:  P63096 GTEx:  ENSG00000127955

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1	C [auth B]	345	Homo sapiens	Mutation(s): 0  Gene Names: GNB1
UniProt & NIH Common Fund Data Resources
Find proteins for P62873 (Homo sapiens) Explore P62873  Go to UniProtKB:  P62873
PHAROS:  P62873 GTEx:  ENSG00000078369

Entity ID: 4
Molecule	Chains	Sequence Length	Organism	Details	Image
Guanine nucleotide-binding protein G(I)/G(S)/G(O) subunit gamma-2	D [auth G]	70	Homo sapiens	Mutation(s): 0  Gene Names: GNG2
UniProt & NIH Common Fund Data Resources
Find proteins for P59768 (Homo sapiens) Explore P59768  Go to UniProtKB:  P59768
PHAROS:  P59768 GTEx:  ENSG00000186469

Entity ID: 5
Molecule	Chains	Sequence Length	Organism	Details	Image
single Fab chain (scFv16)	E [auth S]	250	synthetic construct	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 2.65 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2025-10-29 
Deposition Author(s): Gao, M., Zang, S., Zhu, Y., Mao, C., Zhang, Y., Ma, X.

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Funding Organization	Location	Grant Number
Not funded		--

Revision History  

• Version 1.0: 2025-10-29
  Type: Initial release