Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

Fibrinogen C domain-containing protein 1

Gene

FIBCD1

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Acetyl group-binding receptor which shows a high-affinity and calcium-dependent binding to acetylated structures such as chitin, some N-acetylated carbohydrates, and amino acids, but not to their non-acetylated counterparts. Can facilitate the endocytosis of acetylated components.2 Publications

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Metal bindingi393 – 3931CalciumBy similarity
Metal bindingi395 – 3951CalciumBy similarity
Sitei405 – 4051Implicated in ligand binding
Sitei415 – 4151Implicated in ligand binding
Sitei431 – 4311Implicated in ligand binding
Sitei432 – 4321Implicated in ligand binding

GO - Molecular functioni

  • chitin binding Source: UniProtKB
  • metal ion binding Source: UniProtKB-KW
Complete GO annotation...

Keywords - Ligandi

Calcium, Chitin-binding, Metal-binding

Names & Taxonomyi

Protein namesi
Recommended name:
Fibrinogen C domain-containing protein 1
Gene namesi
Name:FIBCD1
ORF Names:UNQ701/PRO1346
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 9

Organism-specific databases

HGNCiHGNC:25922. FIBCD1.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 3333CytoplasmicSequence analysisAdd
BLAST
Transmembranei34 – 5421Helical; Signal-anchor for type II membrane proteinSequence analysisAdd
BLAST
Topological domaini55 – 461407ExtracellularSequence analysisAdd
BLAST

GO - Cellular componenti

  • integral component of membrane Source: UniProtKB-KW
  • membrane Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Membrane

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi393 – 3931D → N: Complete loss of binding to acetylated bovine serum albumin and reduced binding to chitin; when associated with A-395. 1 Publication
Mutagenesisi395 – 3951D → A: Complete loss of binding to acetylated bovine serum albumin and reduced binding to chitin; when associated with N-395. 1 Publication
Mutagenesisi405 – 4051Y → S: Significantly reduced binding to acetylated bovine serum albumin and loss of binding to chitin; when associated with S-431. 1 Publication
Mutagenesisi415 – 4151H → G: Complete loss of binding to acetylated bovine serum albumin and chitin. 1 Publication
Mutagenesisi431 – 4311Y → S: Significantly reduced binding to acetylated bovine serum albumin and loss of binding to chitin; when associated with S-405. 1 Publication
Mutagenesisi432 – 4321A → V: Complete loss of binding to acetylated bovine serum albumin and chitin. 1 Publication
Mutagenesisi443 – 4431W → S: Slight reduction in binding to acetylated bovine serum albumin and no effect on binding to chitin. 1 Publication

Organism-specific databases

PharmGKBiPA134891641.

Polymorphism and mutation databases

BioMutaiFIBCD1.
DMDMi152032456.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 461461Fibrinogen C domain-containing protein 1PRO_0000294315Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi244 ↔ 273PROSITE-ProRule annotation
Glycosylationi340 – 3401N-linked (GlcNAc...)Sequence analysis
Disulfide bondi401 ↔ 414PROSITE-ProRule annotation

Keywords - PTMi

Disulfide bond, Glycoprotein

Proteomic databases

PaxDbiQ8N539.
PRIDEiQ8N539.

PTM databases

iPTMnetiQ8N539.
PhosphoSiteiQ8N539.

Expressioni

Tissue specificityi

Expressed in the small and large intestinal epithelial cells with a highly polarized localization to the apical surface corresponding to the brush border and in the ducts of the salivary gland.1 Publication

Gene expression databases

BgeeiQ8N539.
CleanExiHS_FIBCD1.
ExpressionAtlasiQ8N539. baseline and differential.
GenevisibleiQ8N539. HS.

Organism-specific databases

HPAiHPA053898.
HPA055353.

Interactioni

Subunit structurei

Homotetramer; disulfide-linked.2 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
MALP211453EBI-10200808,EBI-3932027

Protein-protein interaction databases

BioGridi124363. 1 interaction.
IntActiQ8N539. 1 interaction.
STRINGi9606.ENSP00000361413.

Structurei

Secondary structure

1
461
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi244 – 2496Combined sources
Beta strandi256 – 2605Combined sources
Beta strandi269 – 2746Combined sources
Helixi277 – 2793Combined sources
Beta strandi282 – 29110Combined sources
Helixi299 – 3046Combined sources
Beta strandi311 – 3144Combined sources
Helixi317 – 3248Combined sources
Beta strandi329 – 3368Combined sources
Beta strandi342 – 35312Combined sources
Turni359 – 3635Combined sources
Beta strandi366 – 37510Combined sources
Helixi380 – 3823Combined sources
Beta strandi395 – 3995Combined sources
Helixi401 – 4044Combined sources
Beta strandi412 – 4143Combined sources
Beta strandi416 – 4183Combined sources
Beta strandi429 – 4324Combined sources
Beta strandi434 – 4374Combined sources
Helixi438 – 4414Combined sources
Beta strandi443 – 4464Combined sources
Beta strandi448 – 4569Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4M7FX-ray2.10A/B236-461[»]
4M7HX-ray2.00A/B236-461[»]
ProteinModelPortaliQ8N539.
SMRiQ8N539. Positions 167-457.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini235 – 458224Fibrinogen C-terminalPROSITE-ProRule annotationAdd
BLAST

Sequence similaritiesi

Contains 1 fibrinogen C-terminal domain.PROSITE-ProRule annotation

Keywords - Domaini

Signal-anchor, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG2579. Eukaryota.
ENOG410ZYS4. LUCA.
GeneTreeiENSGT00830000128240.
HOGENOMiHOG000037127.
HOVERGENiHBG001644.
InParanoidiQ8N539.
OMAiRDNDHSE.
PhylomeDBiQ8N539.
TreeFamiTF351983.

Family and domain databases

Gene3Di3.90.215.10. 1 hit.
4.10.530.10. 1 hit.
InterProiIPR014716. Fibrinogen_a/b/g_C_1.
IPR014715. Fibrinogen_a/b/g_C_2.
IPR002181. Fibrinogen_a/b/g_C_dom.
IPR020837. Fibrinogen_CS.
[Graphical view]
PfamiPF00147. Fibrinogen_C. 1 hit.
[Graphical view]
SMARTiSM00186. FBG. 1 hit.
[Graphical view]
SUPFAMiSSF56496. SSF56496. 1 hit.
PROSITEiPS00514. FIBRINOGEN_C_1. 1 hit.
PS51406. FIBRINOGEN_C_2. 1 hit.
[Graphical view]

Sequences (2)i

Sequence statusi: Complete.

This entry describes 2 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q8N539-1) [UniParc]FASTAAdd to basket

This isoform has been chosen as the 'canonical' sequence. All positional information in this entry refers to it. This is also the sequence that appears in the downloadable versions of the entry.

« Hide

        10         20         30         40         50
MVNDRWKTMG GAAQLEDRPR DKPQRPSCGY VLCTVLLALA VLLAVAVTGA
60 70 80 90 100
VLFLNHAHAP GTAPPPVVST GAASANSALV TVERADSSHL SILIDPRCPD
110 120 130 140 150
LTDSFARLES AQASVLQALT EHQAQPRLVG DQEQELLDTL ADQLPRLLAR
160 170 180 190 200
ASELQTECMG LRKGHGTLGQ GLSALQSEQG RLIQLLSESQ GHMAHLVNSV
210 220 230 240 250
SDILDALQRD RGLGRPRNKA DLQRAPARGT RPRGCATGSR PRDCLDVLLS
260 270 280 290 300
GQQDDGVYSV FPTHYPAGFQ VYCDMRTDGG GWTVFQRRED GSVNFFRGWD
310 320 330 340 350
AYRDGFGRLT GEHWLGLKRI HALTTQAAYE LHVDLEDFEN GTAYARYGSF
360 370 380 390 400
GVGLFSVDPE EDGYPLTVAD YSGTAGDSLL KHSGMRFTTK DRDSDHSENN
410 420 430 440 450
CAAFYRGAWW YRNCHTSNLN GQYLRGAHAS YADGVEWSSW TGWQYSLKFS
460
EMKIRPVRED R
Length:461
Mass (Da):50,744
Last modified:July 10, 2007 - v2
Checksum:iB217DBFD370A3443
GO
Isoform 2 (identifier: Q8N539-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-158: Missing.
     317-357: LKRIHALTTQ...GSFGVGLFSV → PLDRCTLSLA...PPVPGGPTLQ
     358-461: Missing.

Show »
Length:198
Mass (Da):21,564
Checksum:i62988F2B05D27622
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti79 – 791L → V in AAH32953 (PubMed:15489334).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 158158Missing in isoform 2. 1 PublicationVSP_026618Add
BLAST
Alternative sequencei317 – 35741LKRIH…GLFSV → PLDRCTLSLALLVPVAPSPT PPHSFVNVLHPPVPGGPTLQ in isoform 2. 1 PublicationVSP_026619Add
BLAST
Alternative sequencei358 – 461104Missing in isoform 2. 1 PublicationVSP_026620Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY358311 mRNA. Translation: AAQ88678.1.
AK027716 mRNA. Translation: BAB55319.1.
AL161733 Genomic DNA. Translation: CAM45760.1.
AL161733 Genomic DNA. Translation: CAM45761.1.
BC032953 mRNA. Translation: AAH32953.1.
CCDSiCCDS6937.1. [Q8N539-1]
RefSeqiNP_001138578.1. NM_001145106.1. [Q8N539-1]
NP_116232.3. NM_032843.4. [Q8N539-1]
UniGeneiHs.133205.

Genome annotation databases

EnsembliENST00000372338; ENSP00000361413; ENSG00000130720. [Q8N539-1]
ENST00000448616; ENSP00000414501; ENSG00000130720. [Q8N539-1]
GeneIDi84929.
KEGGihsa:84929.
UCSCiuc004bzz.4. human. [Q8N539-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY358311 mRNA. Translation: AAQ88678.1.
AK027716 mRNA. Translation: BAB55319.1.
AL161733 Genomic DNA. Translation: CAM45760.1.
AL161733 Genomic DNA. Translation: CAM45761.1.
BC032953 mRNA. Translation: AAH32953.1.
CCDSiCCDS6937.1. [Q8N539-1]
RefSeqiNP_001138578.1. NM_001145106.1. [Q8N539-1]
NP_116232.3. NM_032843.4. [Q8N539-1]
UniGeneiHs.133205.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4M7FX-ray2.10A/B236-461[»]
4M7HX-ray2.00A/B236-461[»]
ProteinModelPortaliQ8N539.
SMRiQ8N539. Positions 167-457.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi124363. 1 interaction.
IntActiQ8N539. 1 interaction.
STRINGi9606.ENSP00000361413.

PTM databases

iPTMnetiQ8N539.
PhosphoSiteiQ8N539.

Polymorphism and mutation databases

BioMutaiFIBCD1.
DMDMi152032456.

Proteomic databases

PaxDbiQ8N539.
PRIDEiQ8N539.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000372338; ENSP00000361413; ENSG00000130720. [Q8N539-1]
ENST00000448616; ENSP00000414501; ENSG00000130720. [Q8N539-1]
GeneIDi84929.
KEGGihsa:84929.
UCSCiuc004bzz.4. human. [Q8N539-1]

Organism-specific databases

CTDi84929.
GeneCardsiFIBCD1.
H-InvDBHIX0008476.
HGNCiHGNC:25922. FIBCD1.
HPAiHPA053898.
HPA055353.
MIMi613357. gene.
neXtProtiNX_Q8N539.
PharmGKBiPA134891641.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG2579. Eukaryota.
ENOG410ZYS4. LUCA.
GeneTreeiENSGT00830000128240.
HOGENOMiHOG000037127.
HOVERGENiHBG001644.
InParanoidiQ8N539.
OMAiRDNDHSE.
PhylomeDBiQ8N539.
TreeFamiTF351983.

Miscellaneous databases

GenomeRNAii84929.
PROiQ8N539.
SOURCEiSearch...

Gene expression databases

BgeeiQ8N539.
CleanExiHS_FIBCD1.
ExpressionAtlasiQ8N539. baseline and differential.
GenevisibleiQ8N539. HS.

Family and domain databases

Gene3Di3.90.215.10. 1 hit.
4.10.530.10. 1 hit.
InterProiIPR014716. Fibrinogen_a/b/g_C_1.
IPR014715. Fibrinogen_a/b/g_C_2.
IPR002181. Fibrinogen_a/b/g_C_dom.
IPR020837. Fibrinogen_CS.
[Graphical view]
PfamiPF00147. Fibrinogen_C. 1 hit.
[Graphical view]
SMARTiSM00186. FBG. 1 hit.
[Graphical view]
SUPFAMiSSF56496. SSF56496. 1 hit.
PROSITEiPS00514. FIBRINOGEN_C_1. 1 hit.
PS51406. FIBRINOGEN_C_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
  2. "Complete sequencing and characterization of 21,243 full-length human cDNAs."
    Ota T., Suzuki Y., Nishikawa T., Otsuki T., Sugiyama T., Irie R., Wakamatsu A., Hayashi K., Sato H., Nagai K., Kimura K., Makita H., Sekine M., Obayashi M., Nishi T., Shibahara T., Tanaka T., Ishii S.
    , Yamamoto J., Saito K., Kawai Y., Isono Y., Nakamura Y., Nagahari K., Murakami K., Yasuda T., Iwayanagi T., Wagatsuma M., Shiratori A., Sudo H., Hosoiri T., Kaku Y., Kodaira H., Kondo H., Sugawara M., Takahashi M., Kanda K., Yokoi T., Furuya T., Kikkawa E., Omura Y., Abe K., Kamihara K., Katsuta N., Sato K., Tanikawa M., Yamazaki M., Ninomiya K., Ishibashi T., Yamashita H., Murakawa K., Fujimori K., Tanai H., Kimata M., Watanabe M., Hiraoka S., Chiba Y., Ishida S., Ono Y., Takiguchi S., Watanabe S., Yosida M., Hotuta T., Kusano J., Kanehori K., Takahashi-Fujii A., Hara H., Tanase T.-O., Nomura Y., Togiya S., Komai F., Hara R., Takeuchi K., Arita M., Imose N., Musashino K., Yuuki H., Oshima A., Sasaki N., Aotsuka S., Yoshikawa Y., Matsunawa H., Ichihara T., Shiohata N., Sano S., Moriya S., Momiyama H., Satoh N., Takami S., Terashima Y., Suzuki O., Nakagawa S., Senoh A., Mizoguchi H., Goto Y., Shimizu F., Wakebe H., Hishigaki H., Watanabe T., Sugiyama A., Takemoto M., Kawakami B., Yamazaki M., Watanabe K., Kumagai A., Itakura S., Fukuzumi Y., Fujimori Y., Komiyama M., Tashiro H., Tanigami A., Fujiwara T., Ono T., Yamada K., Fujii Y., Ozaki K., Hirao M., Ohmori Y., Kawabata A., Hikiji T., Kobatake N., Inagaki H., Ikema Y., Okamoto S., Okitani R., Kawakami T., Noguchi S., Itoh T., Shigeta K., Senba T., Matsumura K., Nakajima Y., Mizuno T., Morinaga M., Sasaki M., Togashi T., Oyama M., Hata H., Watanabe M., Komatsu T., Mizushima-Sugano J., Satoh T., Shirai Y., Takahashi Y., Nakagawa K., Okumura K., Nagase T., Nomura N., Kikuchi H., Masuho Y., Yamashita R., Nakai K., Yada T., Nakamura Y., Ohara O., Isogai T., Sugano S.
    Nat. Genet. 36:40-45(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 2).
  3. "DNA sequence and analysis of human chromosome 9."
    Humphray S.J., Oliver K., Hunt A.R., Plumb R.W., Loveland J.E., Howe K.L., Andrews T.D., Searle S., Hunt S.E., Scott C.E., Jones M.C., Ainscough R., Almeida J.P., Ambrose K.D., Ashwell R.I.S., Babbage A.K., Babbage S., Bagguley C.L.
    , Bailey J., Banerjee R., Barker D.J., Barlow K.F., Bates K., Beasley H., Beasley O., Bird C.P., Bray-Allen S., Brown A.J., Brown J.Y., Burford D., Burrill W., Burton J., Carder C., Carter N.P., Chapman J.C., Chen Y., Clarke G., Clark S.Y., Clee C.M., Clegg S., Collier R.E., Corby N., Crosier M., Cummings A.T., Davies J., Dhami P., Dunn M., Dutta I., Dyer L.W., Earthrowl M.E., Faulkner L., Fleming C.J., Frankish A., Frankland J.A., French L., Fricker D.G., Garner P., Garnett J., Ghori J., Gilbert J.G.R., Glison C., Grafham D.V., Gribble S., Griffiths C., Griffiths-Jones S., Grocock R., Guy J., Hall R.E., Hammond S., Harley J.L., Harrison E.S.I., Hart E.A., Heath P.D., Henderson C.D., Hopkins B.L., Howard P.J., Howden P.J., Huckle E., Johnson C., Johnson D., Joy A.A., Kay M., Keenan S., Kershaw J.K., Kimberley A.M., King A., Knights A., Laird G.K., Langford C., Lawlor S., Leongamornlert D.A., Leversha M., Lloyd C., Lloyd D.M., Lovell J., Martin S., Mashreghi-Mohammadi M., Matthews L., McLaren S., McLay K.E., McMurray A., Milne S., Nickerson T., Nisbett J., Nordsiek G., Pearce A.V., Peck A.I., Porter K.M., Pandian R., Pelan S., Phillimore B., Povey S., Ramsey Y., Rand V., Scharfe M., Sehra H.K., Shownkeen R., Sims S.K., Skuce C.D., Smith M., Steward C.A., Swarbreck D., Sycamore N., Tester J., Thorpe A., Tracey A., Tromans A., Thomas D.W., Wall M., Wallis J.M., West A.P., Whitehead S.L., Willey D.L., Williams S.A., Wilming L., Wray P.W., Young L., Ashurst J.L., Coulson A., Blocker H., Durbin R.M., Sulston J.E., Hubbard T., Jackson M.J., Bentley D.R., Beck S., Rogers J., Dunham I.
    Nature 429:369-374(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  4. "The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
    The MGC Project Team
    Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Brain.
  5. "Characterization of FIBCD1 as an acetyl group-binding receptor that binds chitin."
    Schlosser A., Thomsen T., Moeller J.B., Nielsen O., Tornoee I., Mollenhauer J., Moestrup S.K., Holmskov U.
    J. Immunol. 183:3800-3809(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, SUBUNIT, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
  6. "The recognition unit of FIBCD1 organizes into a noncovalently linked tetrameric structure and uses a hydrophobic funnel (S1) for acetyl group recognition."
    Thomsen T., Moeller J.B., Schlosser A., Sorensen G.L., Moestrup S.K., Palaniyar N., Wallis R., Mollenhauer J., Holmskov U.
    J. Biol. Chem. 285:1229-1238(2010) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, SUBUNIT, IDENTIFICATION BY MASS SPECTROMETRY, MUTAGENESIS OF ASP-393; ASP-395; TYR-405; HIS-415; TYR-431; ALA-432 AND TRP-443.

Entry informationi

Entry nameiFBCD1_HUMAN
AccessioniPrimary (citable) accession number: Q8N539
Secondary accession number(s): A3KFK0, Q6UXK6, Q96SJ7
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 10, 2007
Last sequence update: July 10, 2007
Last modified: June 8, 2016
This is version 100 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program
DisclaimerAny medical or genetic information present in this entry is provided for research, educational and informational purposes only. It is not in any way intended to be used as a substitute for professional medical advice, diagnosis, treatment or care.

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. Human chromosome 9
    Human chromosome 9: entries, gene names and cross-references to MIM
  2. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  3. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  4. SIMILARITY comments
    Index of protein domains and families

Similar proteinsi

Links to similar proteins from the UniProt Reference Clusters (UniRef) at 100%, 90% and 50% sequence identity:
100%UniRef100 combines identical sequences and sub-fragments with 11 or more residues from any organism into one UniRef entry.
90%UniRef90 is built by clustering UniRef100 sequences that have at least 90% sequence identity to, and 80% overlap with, the longest sequence (a.k.a seed sequence).
50%UniRef50 is built by clustering UniRef90 seed sequences that have at least 50% sequence identity to, and 80% overlap with, the longest sequence in the cluster.