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Protein

Alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase B

Gene

MGAT5B

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

Functioni

Glycosyltransferase that acts on alpha-linked mannose of N-glycans and O-mannosyl glycans. Catalyzes the transfer of N-acetylglucosamine (GlcNAc) to the beta 1-6 linkage of the mannose residue of GlcNAcbeta1,2-Manalpha on both the alpha1,3- and alpha1,6-linked mannose arms in the core structure of N-glycan. Also acts on the GlcNAcbeta1,2-Manalpha1-Ser/Thr moiety, forming a 2,6-branched structure in brain O-mannosyl glycan. Plays an active role in modulating integrin and laminin-dependent adhesion and migration of neuronal cells via its activity in the O-mannosyl glycan pathway.5 Publications

Catalytic activityi

UDP-N-acetyl-D-glucosamine + 6-(2-(N-acetyl-beta-D-glucosaminyl)-alpha-D-mannosyl)-beta-D-mannosyl-R = UDP + 6-(2,6-bis(N-acetyl-beta-D-glucosaminyl)-alpha-D-mannosyl)-beta-D-mannosyl-R.2 Publications

Pathwayi

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Glycosyltransferase, Transferase

Keywords - Ligandi

Metal-binding

Enzyme and pathway databases

BioCyciMetaCyc:HS15606-MONOMER.
UniPathwayiUPA00378.

Protein family/group databases

CAZyiGT18. Glycosyltransferase Family 18.

Names & Taxonomyi

Protein namesi
Recommended name:
Alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase B (EC:2.4.1.-, EC:2.4.1.155)
Alternative name(s):
Alpha-mannoside beta-1,6-N-acetylglucosaminyltransferase B
GlcNAc-T Vb
Short name:
GNT-Vb
Short name:
hGnTVb
Mannoside acetylglucosaminyltransferase 5B
N-acetylglucosaminyl-transferase Vb
N-acetylglucosaminyltransferase IX
Short name:
GNT-IX
Gene namesi
Name:MGAT5B
Synonyms:KIAA2008
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 17

Organism-specific databases

HGNCiHGNC:24140. MGAT5B.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 2424CytoplasmicSequence AnalysisAdd
BLAST
Transmembranei25 – 4521Helical; Signal-anchor for type II membrane proteinSequence AnalysisAdd
BLAST
Topological domaini46 – 792747LumenalSequence AnalysisAdd
BLAST

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Golgi apparatus, Membrane

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA134987427.

Polymorphism and mutation databases

BioMutaiMGAT5B.
DMDMi152040009.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 792792Alpha-1,6-mannosylglycoprotein 6-beta-N-acetylglucosaminyltransferase BPRO_0000288611Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Glycosylationi127 – 1271N-linked (GlcNAc...)Sequence Analysis

Keywords - PTMi

Glycoprotein

Proteomic databases

MaxQBiQ3V5L5.
PaxDbiQ3V5L5.
PRIDEiQ3V5L5.

Expressioni

Tissue specificityi

Predominantly expressed in brain. Expressed in all area of the adult and fetal brain Also expressed at much lower level in testis, spleen and thymus.2 Publications

Gene expression databases

BgeeiQ3V5L5.
CleanExiHS_MGAT5B.
ExpressionAtlasiQ3V5L5. baseline and differential.
GenevestigatoriQ3V5L5.

Organism-specific databases

HPAiHPA017424.

Interactioni

Binary interactionsi

WithEntry#Exp.IntActNotes
Hoxa1P090223EBI-3957727,EBI-3957603From a different organism.

Protein-protein interaction databases

BioGridi127000. 22 interactions.
IntActiQ3V5L5. 2 interactions.
STRINGi9606.ENSP00000391227.

Structurei

3D structure databases

ProteinModelPortaliQ3V5L5.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Belongs to the glycosyltransferase 18 family.Curated

Keywords - Domaini

Signal-anchor, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG270839.
GeneTreeiENSGT00390000012263.
HOGENOMiHOG000006557.
HOVERGENiHBG052469.
InParanoidiQ3V5L5.
KOiK09661.
OMAiNHLYPAF.
OrthoDBiEOG71K629.
PhylomeDBiQ3V5L5.
TreeFamiTF313714.

Family and domain databases

InterProiIPR026116. GlyclTrfase_18.
[Graphical view]
PANTHERiPTHR15075. PTHR15075. 1 hit.

Sequences (3)i

Sequence statusi: Complete.

This entry describes 3 isoformsi produced by alternative splicing. AlignAdd to basket

Isoform 1 (identifier: Q3V5L5-1) [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
MITVNPDGKI MVRRCLVTLR PFRLFVLGIG FFTLCFLMTS LGGQFSARRL
60 70 80 90 100
GDSPFTIRTE VMGGPESRGV LRKMSDLLEL MVKRMDALAR LENSSELHRA
110 120 130 140 150
GGDLHFPADR MPPGAGLMER IQAIAQNVSD IAVKVDQILR HSLLLHSKVS
160 170 180 190 200
EGRRDQCEAP SDPKFPDCSG KVEWMRARWT SDPCYAFFGV DGTECSFLIY
210 220 230 240 250
LSEVEWFCPP LPWRNQTAAQ RAPKPLPKVQ AVFRSNLSHL LDLMGSGKES
260 270 280 290 300
LIFMKKRTKR LTAQWALAAQ RLAQKLGATQ RDQKQILVHI GFLTEESGDV
310 320 330 340 350
FSPRVLKGGP LGEMVQWADI LTALYVLGHG LRVTVSLKEL QSNLGVPPGR
360 370 380 390 400
GSCPLTMPLP FDLIYTDYHG LQQMKRHMGL SFKKYRCRIR VIDTFGTEPA
410 420 430 440 450
YNHEEYATLH GYRTNWGYWN LNPKQFMTMF PHTPDNSFMG FVSEELNETE
460 470 480 490 500
KRLIKGGKAS NMAVVYGKEA SIWKLQGKEK FLGILNKYME IHGTVYYESQ
510 520 530 540 550
RPPEVPAFVK NHGLLPQPEF QQLLRKAKLF IGFGFPYEGP APLEAIANGC
560 570 580 590 600
IFLQSRFSPP HSSLNHEFFR GKPTSREVFS QHPYAENFIG KPHVWTVDYN
610 620 630 640 650
NSEEFEAAIK AIMRTQVDPY LPYEYTCEGM LERIHAYIQH QDFCRAPDPA
660 670 680 690 700
LPEAHAPQSP FVLAPNATHL EWARNTSLAP GAWPPAHALR AWLAVPGRAC
710 720 730 740 750
TDTCLDHGLI CEPSFFPFLN SQDAFLKLQV PCDSTESEMN HLYPAFAQPG
760 770 780 790
QECYLQKEPL LFSCAGSNTK YRRLCPCRDF RKGQVALCQG CL
Length:792
Mass (Da):89,535
Last modified:May 29, 2007 - v2
Checksum:iC2EB9445FDBE9429
GO
Isoform 2 (identifier: Q3V5L5-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-22: MITVNPDGKIMVRRCLVTLRPF → MHSFVKHLCSRYVVERQGTMALPALLTRLLPLR
     475-476: Missing.

Show »
Length:801
Mass (Da):90,571
Checksum:iB5EC03A96DBFB38B
GO
Isoform 3 (identifier: Q3V5L5-5) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     475-476: Missing.

Show »
Length:790
Mass (Da):89,294
Checksum:i22193B688EFFACFF
GO

Sequence cautioni

The sequence AAH62354.1 differs from that shown.Probable cloning artifact.Curated
The sequence AAH63862.1 differs from that shown.Probable cloning artifact.Curated
The sequence BAB71598.1 differs from that shown.Chimeric sequence.Curated
The sequence BAD02406.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated
The sequence BAE44474.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally shortened.Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti70 – 701V → I.
Corresponds to variant rs571264 [ dbSNP | Ensembl ].
VAR_032452

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 2222MITVN…TLRPF → MHSFVKHLCSRYVVERQGTM ALPALLTRLLPLR in isoform 2. 1 PublicationVSP_025731Add
BLAST
Alternative sequencei475 – 4762Missing in isoform 2 and isoform 3. 1 PublicationVSP_025734

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB114297 mRNA. Translation: BAD02406.1. Different initiation.
AB109185 mRNA. Translation: BAC84969.1.
AB235153 mRNA. Translation: BAE44474.1. Different initiation.
AC016168 Genomic DNA. No translation available.
BC062354 mRNA. Translation: AAH62354.1. Sequence problems.
BC063862 mRNA. Translation: AAH63862.1. Sequence problems.
AK057861 mRNA. Translation: BAB71598.1. Sequence problems.
CCDSiCCDS11751.1. [Q3V5L5-5]
CCDS45788.1. [Q3V5L5-2]
CCDS59299.1. [Q3V5L5-1]
RefSeqiNP_001186101.1. NM_001199172.1. [Q3V5L5-1]
NP_653278.2. NM_144677.2. [Q3V5L5-5]
NP_945193.1. NM_198955.1. [Q3V5L5-2]
UniGeneiHs.144531.

Genome annotation databases

EnsembliENST00000301618; ENSP00000301618; ENSG00000167889. [Q3V5L5-5]
ENST00000428789; ENSP00000391227; ENSG00000167889. [Q3V5L5-2]
ENST00000569840; ENSP00000456037; ENSG00000167889. [Q3V5L5-1]
GeneIDi146664.
KEGGihsa:146664.
UCSCiuc002jth.3. human. [Q3V5L5-5]
uc002jti.3. human. [Q3V5L5-2]
uc031rem.1. human. [Q3V5L5-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Web resourcesi

GGDB

GlycoGene database

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB114297 mRNA. Translation: BAD02406.1. Different initiation.
AB109185 mRNA. Translation: BAC84969.1.
AB235153 mRNA. Translation: BAE44474.1. Different initiation.
AC016168 Genomic DNA. No translation available.
BC062354 mRNA. Translation: AAH62354.1. Sequence problems.
BC063862 mRNA. Translation: AAH63862.1. Sequence problems.
AK057861 mRNA. Translation: BAB71598.1. Sequence problems.
CCDSiCCDS11751.1. [Q3V5L5-5]
CCDS45788.1. [Q3V5L5-2]
CCDS59299.1. [Q3V5L5-1]
RefSeqiNP_001186101.1. NM_001199172.1. [Q3V5L5-1]
NP_653278.2. NM_144677.2. [Q3V5L5-5]
NP_945193.1. NM_198955.1. [Q3V5L5-2]
UniGeneiHs.144531.

3D structure databases

ProteinModelPortaliQ3V5L5.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi127000. 22 interactions.
IntActiQ3V5L5. 2 interactions.
STRINGi9606.ENSP00000391227.

Protein family/group databases

CAZyiGT18. Glycosyltransferase Family 18.

Polymorphism and mutation databases

BioMutaiMGAT5B.
DMDMi152040009.

Proteomic databases

MaxQBiQ3V5L5.
PaxDbiQ3V5L5.
PRIDEiQ3V5L5.

Protocols and materials databases

DNASUi146664.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000301618; ENSP00000301618; ENSG00000167889. [Q3V5L5-5]
ENST00000428789; ENSP00000391227; ENSG00000167889. [Q3V5L5-2]
ENST00000569840; ENSP00000456037; ENSG00000167889. [Q3V5L5-1]
GeneIDi146664.
KEGGihsa:146664.
UCSCiuc002jth.3. human. [Q3V5L5-5]
uc002jti.3. human. [Q3V5L5-2]
uc031rem.1. human. [Q3V5L5-1]

Organism-specific databases

CTDi146664.
GeneCardsiGC17P074864.
HGNCiHGNC:24140. MGAT5B.
HPAiHPA017424.
MIMi612441. gene.
neXtProtiNX_Q3V5L5.
PharmGKBiPA134987427.
HUGEiSearch...
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG270839.
GeneTreeiENSGT00390000012263.
HOGENOMiHOG000006557.
HOVERGENiHBG052469.
InParanoidiQ3V5L5.
KOiK09661.
OMAiNHLYPAF.
OrthoDBiEOG71K629.
PhylomeDBiQ3V5L5.
TreeFamiTF313714.

Enzyme and pathway databases

UniPathwayiUPA00378.
BioCyciMetaCyc:HS15606-MONOMER.

Miscellaneous databases

ChiTaRSiMGAT5B. human.
GeneWikiiMGAT5B.
GenomeRNAii146664.
NextBioi85408.
PROiQ3V5L5.
SOURCEiSearch...

Gene expression databases

BgeeiQ3V5L5.
CleanExiHS_MGAT5B.
ExpressionAtlasiQ3V5L5. baseline and differential.
GenevestigatoriQ3V5L5.

Family and domain databases

InterProiIPR026116. GlyclTrfase_18.
[Graphical view]
PANTHERiPTHR15075. PTHR15075. 1 hit.
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 2), ENZYME ACTIVITY, FUNCTION, TISSUE SPECIFICITY.
  2. "Molecular cloning and characterization of human GnT-IX, a novel beta1,6-N-acetylglucosaminyltransferase that is specifically expressed in the brain."
    Inamori K., Endo T., Ide Y., Fujii S., Gu J., Honke K., Taniguchi N.
    J. Biol. Chem. 278:43102-43109(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1), ENZYME ACTIVITY, FUNCTION, TISSUE SPECIFICITY.
    Tissue: Brain.
  3. "The nucleotide sequence of a long cDNA clone isolated from human."
    Nagase T., Kikuno R., Ohara O.
    Submitted (NOV-2002) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ISOFORM 1).
    Tissue: Brain.
  4. "DNA sequence of human chromosome 17 and analysis of rearrangement in the human lineage."
    Zody M.C., Garber M., Adams D.J., Sharpe T., Harrow J., Lupski J.R., Nicholson C., Searle S.M., Wilming L., Young S.K., Abouelleil A., Allen N.R., Bi W., Bloom T., Borowsky M.L., Bugalter B.E., Butler J., Chang J.L.
    , Chen C.-K., Cook A., Corum B., Cuomo C.A., de Jong P.J., DeCaprio D., Dewar K., FitzGerald M., Gilbert J., Gibson R., Gnerre S., Goldstein S., Grafham D.V., Grocock R., Hafez N., Hagopian D.S., Hart E., Norman C.H., Humphray S., Jaffe D.B., Jones M., Kamal M., Khodiyar V.K., LaButti K., Laird G., Lehoczky J., Liu X., Lokyitsang T., Loveland J., Lui A., Macdonald P., Major J.E., Matthews L., Mauceli E., McCarroll S.A., Mihalev A.H., Mudge J., Nguyen C., Nicol R., O'Leary S.B., Osoegawa K., Schwartz D.C., Shaw-Smith C., Stankiewicz P., Steward C., Swarbreck D., Venkataraman V., Whittaker C.A., Yang X., Zimmer A.R., Bradley A., Hubbard T., Birren B.W., Rogers J., Lander E.S., Nusbaum C.
    Nature 440:1045-1049(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  5. "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] OF 1-341 (ISOFORMS 1/3), NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 616-792.
    Tissue: PNS and Skin.
  6. "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] OF 100-306.
    Tissue: Brain.
  7. "N-Acetylglucosaminyltransferase IX acts on the GlcNAc beta 1,2-Man alpha 1-Ser/Thr moiety, forming a 2,6-branched structure in brain O-mannosyl glycan."
    Inamori K., Endo T., Gu J., Matsuo I., Ito Y., Fujii S., Iwasaki H., Narimatsu H., Miyoshi E., Honke K., Taniguchi N.
    J. Biol. Chem. 279:2337-2340(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION.
  8. "Integrin-dependent neuroblastoma cell adhesion and migration on laminin is regulated by expression levels of two enzymes in the O-mannosyl-linked glycosylation pathway, PomGnT1 and GnT-Vb."
    Abbott K.L., Troupe K., Lee I., Pierce M.
    Exp. Cell Res. 312:2837-2850(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION.
  9. "N-acetylglucosaminyltransferase VB expression enhances beta1 integrin-dependent PC12 neurite outgrowth on laminin and collagen."
    Lee I., Guo H.-B., Kamar M., Abbott K., Troupe K., Lee J.-K., Alvarez-Manilla G., Pierce M.
    J. Neurochem. 97:947-956(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION.

Entry informationi

Entry nameiMGT5B_HUMAN
AccessioniPrimary (citable) accession number: Q3V5L5
Secondary accession number(s): Q6P3S8
, Q6P6B3, Q766X5, Q76D04, Q96LS2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: May 29, 2007
Last sequence update: May 29, 2007
Last modified: April 29, 2015
This is version 90 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

Complete proteome, Reference proteome

Documents

  1. Human chromosome 17
    Human chromosome 17: entries, gene names and cross-references to MIM
  2. Human entries with polymorphisms or disease mutations
    List of human entries with polymorphisms or disease mutations
  3. Human polymorphisms and disease mutations
    Index of human polymorphisms and disease mutations
  4. MIM cross-references
    Online Mendelian Inheritance in Man (MIM) cross-references in UniProtKB/Swiss-Prot
  5. PATHWAY comments
    Index of metabolic and biosynthesis pathways
  6. SIMILARITY comments
    Index of protein domains and families

External Data

Dasty 3

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 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.