4MRM: Extracellular domain of human GABA(B) receptor

Crystal structure of the extracellular domain of human GABA(B) receptor bound to the antagonist phaclofen. Determined by X-ray diffraction at 2.86 Å resolution. Released 11 Dec 2013.

Method: X-ray diffraction
Resolution: 2.86 Å
Organism: Homo sapiens
Chains: 2
Atoms: 6,753
Mol. weight: 98.42 kDa
Ligands: NAG, 2BY
Released: 11 Dec 2013

Explore 4MRM in 3D Show helices and sheets RCSB PDB PDBe

Secondary structure: helices and β-sheets

4MRM contains 42 α-helices and 34 β-strands across 2 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: 22 helices, 18 β-strands

Element	Residues	Length	Sheet
α-helix	50	1
β-strand	51-59	9	1
α-helix	68-83	16
β-strand	92-100	9	1
α-helix	105-116	12
α-helix	121	1
β-strand	124-126	3	1
α-helix	130-139	10
α-helix	140-143	4
β-strand	146-149	4	1
α-helix	155-157	3
β-strand	166-168	3	1
α-helix	171-172	2
α-helix	173-175	3
α-helix	176-186	11
β-strand	191-197	7	2
α-helix	200-214	15
β-strand	219-226	8	2
α-helix	231-239	9
β-strand	244-248	5	2
α-helix	251-263	13
β-strand	272-276	5	2
α-helix	280	1
α-helix	295-302	8
β-strand	306-310	5	2
α-helix	326-336	11
α-helix	341-343	3
α-helix	350-367	18
α-helix	378-380	3
α-helix	387-397	11
β-strand	401-403	3	3
β-strand	406-408	3	3
β-strand	410	1	4
β-strand	415	1	1
β-strand	416	1	4
α-helix	417	1
β-strand	420-426	7	2
β-strand	429-437	9	2
β-strand	442-445	4	2
α-helix	452-454	3

Chain B: 20 helices, 16 β-strands

Element	Residues	Length	Sheet
β-strand	55-62	8	5
α-helix	71-90	20
β-strand	98-105	8	5
α-helix	110-123	14
β-strand	129-132	4	5
α-helix	136-145	10
α-helix	146-149	4
β-strand	152-155	4	5
α-helix	161-164	4
β-strand	172-174	3	5
α-helix	177-178	2
α-helix	179-181	3
α-helix	182-192	11
β-strand	197-203	7	6
α-helix	206-219	14
β-strand	225-232	8	6
α-helix	237-245	9
β-strand	250-254	5	6
α-helix	257-269	13
β-strand	278-282	5	6
α-helix	285-286	2
α-helix	304-311	8
α-helix	314	1
β-strand	315-319	5	6
α-helix	335-346	12
α-helix	350-351	2
α-helix	355-377	23
α-helix	393-404	12
β-strand	407-410	4	7
β-strand	413-418	6	7
β-strand	421-423	3	7
β-strand	425-432	8	6
β-strand	435-443	9	6
β-strand	448-451	4	6
α-helix	452	1
α-helix	463-465	3

Molecules and chains

Molecule	Chains	Type	Length	Organism	UniProt
Gamma-aminobutyric acid type B receptor subunit 1	A	protein	420	Homo sapiens	Q9UBS5 (AlphaFold model)
Gamma-aminobutyric acid type B receptor subunit 2	B	protein	433	Homo sapiens	O75899 (AlphaFold model)

Sequence of entity 1 (A), FASTA

>4MRM_1 Gamma-aminobutyric acid type B receptor subunit 1 (chains A)
SERRAVYIGALFPMSGGWPGGQACQPAVEMALEDVNSRRDILPDYELKLIHHDSKCDPGQ
ATKYLYELLYNDPIKIILMPGCSSVSTLVAEAARMWNLIVLSYGSSSPALSNRQRFPTFF
RTHPSATLHNPTRVKLFEKWGWKKIATIQQTTEVFTSTLDDLEERVKEAGIEITFRQSFF
SDPAVPVKNLKRQDARIIVGLFYETEARKVFCEVYKERLFGKKYVWFLIGWYADNWFKIY
DPSINCTVDEMTEAVEGHITTEIVMLNPANTRSISNMTSQEFVEKLTKRLKRHPEETGGF
QEAPLAYDAIWALALALNKTSGGGGRSGVRLEDFNYNNQTITDQIYRAMNSSSFEGVSGH
VVFDASGSRMAWTLIEQLQGGSYKKIGYYDSTKDDLSWSKTDKWIGGSPPADDYKDDDDK

Sequence of entity 2 (B), FASTA

>4MRM_2 Gamma-aminobutyric acid type B receptor subunit 2 (chains B)
WARGAPRPPPSSPPLSIMGLMPLTKEVAKGSIGRGVLPAVELAIEQIRNESLLRPYFLDL
RLYDTECDNAKGLKAFYDAIKYGPNHLMVFGGVCPSVTSIIAESLQGWNLVQLSFAATTP
VLADKKKYPYFFRTVPSDNAVNPAILKLLKHYQWKRVGTLTQDVQRFSEVRNDLTGVLYG
EDIEISDTESFSNDPCTSVKKLKGNDVRIILGQFDQNMAAKVFCCAYEENMYGSKYQWII
PGWYEPSWWEQVHTEANSSRCLRKNLLAAMEGYIGVDFEPLSSKQIKTISGKTPQQYERE
YNNKRSGVGPSKFHGYAYDGIWVIAKTLQRAMETLHASSRHQRIQDFNYTDHTLGRIILN
AMNETNFFGVTGQVVFRNGERMGTIKFTQFQDSREVKVGEYNAVADTLEIINDTIRFQGS
EPPKDDYKDDDDK

Ligands and cofactors

ID	Name	Formula	Copies
NAG	2-acetamido-2-deoxy-beta-D-glucopyranose	C8 H15 N O6	1
2BY	phaclofen	C9 H13 Cl N O3 P	1

Primary citation

Structural mechanism of ligand activation in human GABA(B) receptor. Geng, Y., Bush, M., Mosyak, L. et al. Nature (2013) 504:254-259. DOI 10.1038/nature12725 · PubMed

Other PDB entries of the same protein (UniProt Q9UBS5 (AlphaFold model), which also has an AlphaFold model), best resolution first:

4PAS 1.62 Å, Heterodimeric coiled-coil structure of human GABA(B) receptor
4MS4 1.9 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MR7 2.15 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MR8 2.15 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MQF 2.22 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MS1 2.25 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MQE 2.35 Å, Crystal structure of the extracellular domain of human GABA(B) receptor in the apo form
4MR9 2.35 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
4MS3 2.5 Å, Crystal structure of the extracellular domain of human GABA(B) receptor bound to the…
7C7S 2.9 Å, Cryo-EM structure of the CGP54626-bound human GABA(B) receptor in inactive state.
7C7Q 3.0 Å, Cryo-EM structure of the baclofen/BHFF-bound human GABA(B) receptor in active state
6W2Y 3.2 Å, CryoEM Structure of GABAB1b Homodimer

Browse structure collections

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