CODSWALLOP

Green fluorescent protein

Aequorea victoria · seed P42212 · 238 aa · family defined as ≥30% identity to that seed · compiled 07 October 2026

CATH and SCOP identifiers come from the RCSB's own structure annotations, which the Domains panel already reads, so these are looked up rather than guessed at.

1,174Entries 1,212Entities 697Constructs 73Organisms 295Ligand-bound
0.77 ÅBest res.
2.20 ÅMedian res.

Every figure here is counted over the whole family rather than quoted from one entry.

The reference structure

1KYP, the structure every other member of this family is superposed onto. Rendered by the RCSB and embedded here: the live app shows an interactive viewport, which a document that fetches nothing cannot.

Rendered structure of 1KYP
1KYP at the RCSB · open it in the 3D viewer

Which residues anyone has ever seen

How many of this family's constructs contain each residue of the seed. A trough is a stretch nobody has put in a construct, which is a construct-design answer rather than a disorder one.

11192381204 constructs

Constructs, most-used first

697 distinct constructs across 1,174 entries. 954 polymer entities differ from the UniProt canonical sequence in some way, 461 carry a recognised expression tag and 91 carry a fusion partner.

"Differs from canonical" is not the same as "engineered". The canonical sequence is the full gene product, so a secreted protein whose structures all start after its signal peptide counts every one of them as different: lysozyme's most-used construct, residues 19–147 on 1,239 entities, is simply the mature protein. Read the construct column below for what was actually done, rather than this count.

EntitiesLengthBest (Å)Best entryWhat was made
26 241 1.23 3DQ7 1 internal deletion; M1V, V68L, Q69M +3 more
15 252 1.46 8A7V His6; M1V, F64L, S65A +4 more
15 753 2.98 24VI His8+Strep-II; 3C/PreScission site; M1V, F64L, S65T +3 more
15 861 2.70 7V8A M1G, S30R, Y39N +10 more
12 220 1.31 7QLO residues 1-222; 1 internal deletion; N11K, E70K, H74N +8 more
9 245 1.40 5MA4 M1V, F64L, S65T +1 more
8 272 1.50 6UHJ His6+T7; Enterokinase site; 1 internal deletion; M1V, C48L, F64L +2 more
8 623 3.10 9HNS His6; TEV site; M1V, L18M, H25R +22 more
8 679 3.10 9HNS Strep-II; TEV site; S30R, Y39N, F64L +9 more
7 231 2.35 4W76 no UniProt reference for this entity, so it cannot be diffed against a canonical sequence
7 239 1.02 5OXC M1V, F64L, S65T +8 more
7 253 1.83 8SFV His6; 3C/PreScission site; 1 internal deletion; M1A, S72A, Q177H
7 632 2.72 8U4N FLAG; 3C/PreScission site; M1V, F64L, S65T +2 more
7 680 3.55 8DN3 M1V
6 236 1.45 1Q4A 1 internal deletion; Q80R
6 236 1.70 4W6J no UniProt reference for this entity, so it cannot be diffed against a canonical sequence
6 705 2.54 9LEZ FLAG+Strep-II; 3C/PreScission site; residues 1-241; M1S, G2R, S3M
6 1291 2.71 9W98 fused to GFP, MBP (internal); 1 internal deletion; M1I, D2T, K4S +2 more
6 1315 3.00 9YP9 Avi+FLAG; M1V, F64L, S65T +1 more
6 1622 2.65 9U3P FLAG+His10; fused to GFP; TEV site
5 222 1.02 7QLJ residues 1-222; N11K, H62A, E70K +9 more
5 244 1.65 6GO8 S65A, V68L, S72A
5 251 1.18 6OGC residues 24-238; 2 internal deletions; K26H, F27H, S28H +20 more
5 258 1.16 3SRY FLAG+His6; 1 internal deletion; M1V, S72A, K79R +3 more
5 258 1.19 3ST0 FLAG+His6; 1 internal deletion; M1V, Q69T, S72A +4 more

Showing the 25 most-used of 697.

Positions people deliberately mutate

Columns where the wild-type residue still dominates but a real minority carries something else, which is a different question from "what varies across species".

V163A 62% A206K 62% H231L 61% M153T 53% Y145F 45% F99S 44% I171V 41% N105T 39% S30R 38% Y39N 37% Q80R 35% S72A 34% T203Y 28% S205T 26% H148E 25% N146S 22% S147T 22% S175G 22% K166T 22% Q69L 22% I167L 21% V68L 20% N149K 19% F223Y 19% I128T 18% L194D 18% V150M 18% N198Y 18% S202D 18% Q204I 17%

What it assembles into

Oligomeric stateChainsEntriesShare
monomeric1 633 53.9%
dimeric2 190 16.2%
tetrameric4 147 12.5%
pentameric5 57 4.9%
hexameric6 36 3.1%
octameric8 26 2.2%
trimeric3 24 2.0%
heptameric7 11 0.9%

561 entries have the depositor's assembly corroborated by PISA, 583 carry the depositor's word alone and 29 were assigned by PISA where the depositor gave none. The middle figure is not a disagreement: PISA may have returned nothing or never run. 19 entries carry more than one assembly with different chain counts, so they have no single answer to quote: 1KP5, 2AH8, 2HPW, 3LVC, 3LVD, 3O78, 3P8U, 4OQW, 4W6A, 4W75, 4W76, 4W77, 5FGU, 5J3N, 5KTG, 6B9C, 6DEJ, 6DQ1, 7C03.

Domain architecture

Every source's own domains on the seed axis, one row each. They are not merged: Pfam, CATH, SCOP and InterPro disagree about boundaries, and a merged track would state a consensus none of them gave.

CATHGreen fluorescent proteinSCOP2BGFP-likeGFP-likeGFP-like1119238
DomainSourceSpan (seed)Chains
Green fluorescent proteinCATH 2.40.155.10 5–232 459
GFP-likeSCOP2B 8096046 6–231 425
GFP-likeSCOP2B 8083484 15–230 36
GFP-likeSCOP2B 8101183 37–238 47

What binds it

NAG NAG87 entries POV POV23 entries ADP ADP20 entries YJ0 YJ016 entries A1E7E A1E7E10 entries 6OU 6OU10 entries ABU ABU9 entries 9Z9 9Z96 entries HEX HEX5 entries LBN LBN5 entries P5S P5S5 entries A1CGW A1CGW5 entries
ComponentClassNameEntriesBest (Å)
NAGcofactor 2-Acetamido-2-Deoxy-Beta-D-Glucopyranose 87 2.30
SO4ion Sulfate Ion 85 1.02
GOLcryoprotectant Glycerol 82 1.05
CAion Calcium Ion 73 1.10
MGion Magnesium Ion 67 0.78
EDOcryoprotectant 1,2-Ethanediol 64 1.02
NAion Sodium Ion 59 1.14
CLion Chloride Ion 59 0.94
ZNion Zinc Ion 30 1.44
PO4ion Phosphate Ion 28 1.34
CLRlipid/detergent Cholesterol 26 2.45
PEGcryoprotectant Di(Hydroxyethyl)ether 25 1.35
POVligand (2s)-3-(Hexadecanoyloxy)-2-[(9z)-Octadec-9-Enoyloxy]propyl 2-(Tr 23 2.29
Kion Potassium Ion 21 1.34
CUion Copper (Ii) Ion 20 1.10
ADPcofactor Adenosine-5'-Diphosphate 20 2.60
Y01lipid/detergent Cholesterol Hemisuccinate 19 2.70
YJ0ligand (2r)-2-{[(4-O-Hexopyranosyl-Beta-D-Glucopyranosyl)oxy]methyl}-4- 16 2.77
ACTcryoprotectant Acetate Ion 15 1.15
9PElipid/detergent (1r)-2-{[(S)-(2-Aminoethoxy)(Hydroxy)phosphoryl]oxy}-1-[(Heptano 14 2.98

How it crystallises

Parsed from the free text 773 depositors typed into _exptl_crystal_grow.pdbx_details, out of 777 entries that recorded anything at all. Median pH 7.4 (range 2.0 to 11.0).

Precipitants

PEG × Magnesium chloride × Ammonium sulfate × Sodium chloride × Lithium sulfate × Sodium citrate × MPD × Calcium chloride × Isopropanol × Tacsimate × Sodium formate × Ammonium phosphate × Sodium malonate × PEG (unspecified) ×

Buffers

HEPES × Tris × Sodium acetate × Citrate × MES × Bis-Tris × Phosphate × Sodium cacodylate × Imidazole × Bis-Tris propane × CHES × Glycine × CAPS ×

Which entries to trust

1,171 entries carry a wwPDB validation report: 825 clean, 258 worth a check and 88 with something to explain. Median clashscore 5.78, median RSRZ outliers 2.67%, median R-free minus R-work 0.039. 1,159 have released structure factors.

Across species

OrganismEntriesBest (Å)Ligand-boundSeed covered
Aequorea victoria604 0.77 80 100%
Homo sapiens208 2.25 145 100%
synthetic construct78 1.35 2 100%
Lobophyllia hemprichii45 1.02 0 63%
Rattus norvegicus25 2.03 13 100%
Cytaeis uchidae16 1.45 0 100%
Mus musculus15 2.70 7 100%
Entacmaea quadricolor14 1.50 0 100%
Arabidopsis thaliana13 2.30 0 100%
Escherichia coli12 1.70 8 100%
Gallus gallus11 1.70 0 99%
Clavularia sp.9 1.00 0 100%

Seed sequence

238 residues, numbered every ten. Every identity figure in this document is measured against this sequence.

active or binding site modified residue or glycosylation disulphide cysteine transmembrane or signal the 15 most-substituted positions

1MSKGEELFTG VVPILVELDG DVNGHKFSVS GEGEGDATYG KLTLKFICTT GKLPVPWPTL
61VTTFSYGVQC FSRYPDHMKQ HDFFKSAMPE GYVQERTIFF KDDGNYKTRA EVKFEGDTLV
121NRIELKGIDF KEDGNILGHK LEYNYNSHNV YIMADKQKNG IKVNFKIRHN IEDGSVQLAD
181HYQQNTPIGD GPVLLPDNHY LSTQSALSKD PNEKRDHMVL LEFVTAAGIT HGMDELYK

Sites are UniProt's curated features where the seed is a UniProt accession; the substituted positions are measured from this family's own alignment rather than annotated, and only the fifteen most substituted are marked: every position carrying a minority substitution would be most of the protein, because the family holds orthologues. A residue can carry more than one and is drawn with the first that applies, in the order of the key above.

Primary citations

One record per paper, not per entry.

YearCitation
2026 Structural Basis of the Light-Switchable Interaction between an Azobenzene Side Chain in a Biosynthetic Protein and alpha-Cyclodextrin. Chemistryopen doi:10.1002/open.202500471
2026 Structural and functional insights into the interaction between a PP01 phage gp38 tail fiber tip and an Escherichia coli OmpC receptor. Mbio doi:10.1128/mbio.02110-25
2026 Cryo-EM structure of human AQP11 reveals a trimeric architecture with a large pore. Sci Adv doi:10.1126/sciadv.aeb5769
2026 M18BP1 valency and a distributed interaction footprint determine epigenetic centromere specification in humans. Embo J. doi:10.1038/s44318-026-00698-z
2026 A two-step mechanism for sugar translocation. Nat.Struct.Mol.Biol. doi:10.1038/s41594-026-01784-w
2026 Structural diversity of heat-sensing channel TRPV3 with Olmsted syndrome mutations. Nat Commun doi:10.1038/s41467-026-74687-5
2026 Structural basis of human zinc-activated channel (ZAC) signaling and modulation. Cell Discov doi:10.1038/s41421-026-00878-5
2026 iGABASnFR2 is an improved genetically encoded protein sensor of GABA. Elife doi:10.7554/eLife.108319
2026 Design, synthesis and structural mechanism of action of TRPV1 agonist MSP20 with long-lasting analgesic effect. Nat Commun doi:10.1038/s41467-026-74972-3
2026 Structural insights into the transport and gating mechanisms of the plant high-affinity K + transporter AtHAK5. Mol Plant doi:10.1016/j.molp.2026.08.017
2026 Substrate recognition and allosteric inhibition of human betaine/GABA transporter 1. Nat Commun doi:10.1038/s41467-026-72924-5
2026 Structural insights into measles virus RNA synthesis regulation and pan-paramyxoviral polymerase inhibition by ERDRP-0519. Proc.Natl.Acad.Sci.USA doi:10.1073/pnas.2522978123
2026 A single allosteric site merges activation, modulation and inhibition in TRPM5. Nat.Chem.Biol. doi:10.1038/s41589-025-02097-7
2026 Amino acid and viral binding by the high-affinity Cationic Amino acid Transporter 1 (CAT1) from Mus musculus. Nat Commun doi:10.1038/s41467-026-69421-0
2026 Molecular insight into microtubule nucleation by the XMAP215/ gamma-TuRC module. Nat Commun doi:10.1038/s41467-026-72370-3
2026 Nanobody regulation of C-type inactivation in Kv1.3 channels. Nat Commun doi:10.1038/s41467-026-74630-8
2026 Structural insights into the ligand and G protein recognition by P2Y 13 R. Biochem.Biophys.Res.Commun. doi:10.1016/j.bbrc.2026.153976
2026 Molecular basis of CXC chemokine receptor 3 ligand multispecificity. Sci Adv doi:10.1126/sciadv.adz3767
2026 Structural basis for heteromeric assembly and subthreshold activation of human M-channel Vita doi:10.15302/vita.2026.05.0032
2026 Covalently constrained 'Di-Gembodies' enable parallel structure solutions by cryo-EM. Nat.Chem.Biol. doi:10.1038/s41589-025-01972-7
2026 A novel fusion tool to enable G protein-coupled receptor structure determination. Acta Crystallogr D Struct Biol doi:10.1107/S2059798326003785
2026 Cryo-EM reveals how cardiomyopathy therapeutic drugs modulate the myosin motors of the heart. Sci Adv doi:10.1126/sciadv.aed6472
2026 Biophysical and structural analysis of human green cone opsin. Biophys.J. doi:10.1016/j.bpj.2026.03.029
2026 Tonotopic specialization of MYO7A isoforms in auditory hair cells. Nat Commun doi:10.1038/s41467-026-73220-y
2026 Structural basis for activation and potentiation in a human alpha 5 beta 3 GABA A receptor. Nat Commun doi:10.1038/s41467-026-74279-3
2026 Cryo-EM structure of the bicarbonate receptor GPR30. Elife doi:10.7554/eLife.99874
2026 Structural framework for the assembly of the human tRNA ligase complex. Nat Commun doi:10.1038/s41467-026-77450-y
2026 MDFIC2 is a sensory neuron-specific PIEZO channel auxiliary subunit Proc.Natl.Acad.Sci.USA
2026 Time-Resolved Native Mass Spectrometry for Direct Measurement of Biomolecular Kinetics. J.Am.Chem.Soc. doi:10.1021/jacs.5c21842
2026 A Ligand-Triggered Receptor Conformation Enables the Design of Selective Agonists for the Dopamine 3 Receptor (D 3 R) Using a Bitopic Strategy. Jacs Au doi:10.1021/jacsau.6c00654
2026 The human BAF chromatin remodeler processes nucleosomes bound by pioneer transcription factors OCT4-SOX2. Mol.Cell doi:10.1016/j.molcel.2026.01.021
2026 Evolutionarily conserved short linear motifs drive actin filament binding. Nat.Cell Biol. doi:10.1038/s41556-026-01979-9
2026 Dynamic structures of dengue virus serotype 2 secreted NS1 and their interactions with heparan sulfate. Nat Commun doi:10.1038/s41467-026-71970-3
2026 Structures of partially occupied hetero-tetramers provide insight into kainate receptor activation and desensitization. Nat Commun doi:10.1038/s41467-026-72226-w
2025 Modulating Chromophore Flexibility in GEVIs through Threonine-Based Molecular Switches Reveals an Influence of Membrane Curvature on Protein Activity. ACS Sens doi:10.1021/acssensors.5c01748
2025 Characterization and structural basis for the brightness of mCLIFY: A novel monomeric and circularly permuted bright yellow fluorescent protein. Biophys.J. doi:10.1016/j.bpj.2025.05.012
2025 A unified intracellular pH landscape with SITE-pHorin: a quantum-entanglement-enhanced pH probe. Sci China Life Sci doi:10.1007/s11427-025-2971-5
2025 Molecular features defining the efficiency of bioPROTACs. Commun Biol doi:10.1038/s42003-025-08352-w
2025 Cyan Thermal Proteins Derived From Thermal Green Protein. Proteins doi:10.1002/prot.70003
2025 StayRose: A photostable StayGold derivative redshifted by genetic code expansion. J.Biol.Chem. doi:10.1016/j.jbc.2025.110832