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Protein

EH domain-containing protein 2

Gene

Ehd2

Organism
Mus musculus (Mouse)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Plays a role in membrane reorganization in response to nucleotide hydrolysis. Binds to liposomes and deforms them into tubules. Plays a role in membrane trafficking between the plasma membrane and endosomes. Important for the internalization of GLUT4. Required for fusion of myoblasts to skeletal muscle myotubes. Required for normal translocation of FER1L5 to the plasma membrane. Binds ATP; does not bind GTP.3 Publications

Enzyme regulationi

The very low intrinsic ATPase activity is increased upon interaction with liposomes.1 Publication

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Binding sitei220 – 2201ATP
Binding sitei258 – 2581ATP

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Nucleotide bindingi65 – 728ATP
Calcium bindingi494 – 50512Add
BLAST

GO - Molecular functioni

GO - Biological processi

  • cortical actin cytoskeleton organization Source: MGI
  • endocytic recycling Source: UniProtKB
  • endocytosis Source: MGI
  • positive regulation of endocytic recycling Source: UniProtKB
  • positive regulation of myoblast fusion Source: UniProtKB
  • protein localization to plasma membrane Source: UniProtKB
Complete GO annotation...

Keywords - Molecular functioni

Hydrolase

Keywords - Ligandi

ATP-binding, Calcium, Metal-binding, Nucleotide-binding

Enzyme and pathway databases

ReactomeiREACT_280010. Factors involved in megakaryocyte development and platelet production.

Names & Taxonomyi

Protein namesi
Recommended name:
EH domain-containing protein 2
Gene namesi
Name:Ehd2
OrganismiMus musculus (Mouse)
Taxonomic identifieri10090 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeMusMus
ProteomesiUP000000589 Componenti: Chromosome 7

Organism-specific databases

MGIiMGI:2154274. Ehd2.

Subcellular locationi

GO - Cellular componenti

  • caveola Source: MGI
  • extracellular exosome Source: MGI
  • membrane Source: MGI
  • perinuclear region of cytoplasm Source: MGI
  • plasma membrane Source: UniProtKB
  • recycling endosome membrane Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Endosome, Membrane

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi65 – 651G → R: Inhibits myoblast fusion. 1 Publication
Mutagenesisi72 – 721T → A: Abolishes ATP binding. 1 Publication
Mutagenesisi94 – 941T → A: Abolishes increase of intrinsic ATPase activity upon interaction with membranes. 1 Publication
Mutagenesisi157 – 1571I → Q: Increases intrinsic ATPase activity. 1 Publication
Mutagenesisi167 – 1671R → E: Increases intrinsic ATPase activity. 1 Publication
Mutagenesisi322 – 3221F → A: Abolishes localization at the plasma membrane; reduces increase of intrinsic ATPase activity upon interaction with membranes. 1 Publication
Mutagenesisi324 – 3241K → D: Abolishes localization at the plasma membrane. 1 Publication
Mutagenesisi327 – 3271K → D: Abolishes localization at the plasma membrane; abolishes increase of intrinsic ATPase activity upon interaction with membranes. 1 Publication
Mutagenesisi328 – 3281K → D: Abolishes localization at the plasma membrane; reduces increase of intrinsic ATPase activity upon interaction with membranes. 1 Publication
Mutagenesisi329 – 3291K → D: Abolishes localization at the plasma membrane. 1 Publication

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 543543EH domain-containing protein 2PRO_0000322643Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei1 – 11N-acetylmethionineBy similarity
Modified residuei438 – 4381Phosphoserine2 Publications
Modified residuei468 – 4681PhosphoserineBy similarity

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiQ8BH64.
PaxDbiQ8BH64.
PRIDEiQ8BH64.

PTM databases

PhosphoSiteiQ8BH64.

Expressioni

Tissue specificityi

Detected in lung and adipocytes. Detected at lower levels in heart and skeletal muscle.1 Publication

Gene expression databases

BgeeiQ8BH64.
CleanExiMM_EHD2.
ExpressionAtlasiQ8BH64. baseline and differential.
GenevisibleiQ8BH64. MM.

Interactioni

Subunit structurei

Interacts with EHD1. May also interact with EHD3 and EHD4 (By similarity). Interacts with Asn-Pro-Phe (NPF) motifs in target proteins. Homodimer and homooligomer. Interacts with MYOF and EHBP1. Interacts with FER1L5 (via second C2 domain).By similarity4 Publications

Protein-protein interaction databases

DIPiDIP-46806N.
IntActiQ8BH64. 2 interactions.
STRINGi10090.ENSMUSP00000096397.

Structurei

Secondary structure

1
543
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Helixi21 – 3212Combined sources
Helixi34 – 396Combined sources
Helixi42 – 443Combined sources
Helixi52 – 565Combined sources
Beta strandi60 – 667Combined sources
Helixi71 – 799Combined sources
Beta strandi96 – 1027Combined sources
Beta strandi104 – 1096Combined sources
Beta strandi134 – 1418Combined sources
Helixi145 – 1473Combined sources
Beta strandi150 – 1534Combined sources
Helixi171 – 18111Combined sources
Beta strandi183 – 1908Combined sources
Helixi191 – 1933Combined sources
Helixi198 – 20710Combined sources
Helixi211 – 2133Combined sources
Beta strandi214 – 2196Combined sources
Turni220 – 2234Combined sources
Helixi226 – 24419Combined sources
Beta strandi252 – 2554Combined sources
Beta strandi258 – 2603Combined sources
Helixi268 – 28316Combined sources
Turni284 – 2885Combined sources
Helixi289 – 31729Combined sources
Beta strandi320 – 3234Combined sources
Helixi324 – 34623Combined sources
Helixi350 – 3523Combined sources
Helixi356 – 3649Combined sources
Helixi368 – 3703Combined sources
Helixi376 – 38712Combined sources
Helixi389 – 40315Combined sources
Helixi405 – 4073Combined sources
Beta strandi411 – 4144Combined sources
Helixi416 – 4194Combined sources
Helixi447 – 45913Combined sources
Beta strandi466 – 4683Combined sources
Helixi469 – 4768Combined sources
Helixi477 – 4793Combined sources
Helixi483 – 49311Combined sources
Beta strandi498 – 5025Combined sources
Helixi503 – 51816Combined sources
Helixi528 – 5303Combined sources
Helixi533 – 5353Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2QPTX-ray3.10A1-543[»]
4CIDX-ray3.00A5-543[»]
ProteinModelPortaliQ8BH64.
SMRiQ8BH64. Positions 1-539.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiQ8BH64.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini55 – 286232Dynamin-type GAdd
BLAST
Domaini449 – 53789EHPROSITE-ProRule annotationAdd
BLAST
Domaini481 – 51636EF-handPROSITE-ProRule annotationAdd
BLAST

Domaini

The EH domain interacts with Asn-Pro-Phe (NPF) motifs of target proteins.

Sequence similaritiesi

Contains 1 EF-hand domain.PROSITE-ProRule annotation
Contains 1 EH domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiNOG136252.
GeneTreeiENSGT00760000118985.
HOGENOMiHOG000242040.
HOVERGENiHBG018183.
InParanoidiQ8BH64.
KOiK12469.
OMAiMQEMLMA.
OrthoDBiEOG757CX9.
PhylomeDBiQ8BH64.
TreeFamiTF314429.

Family and domain databases

Gene3Di1.10.238.10. 1 hit.
3.40.50.300. 2 hits.
InterProiIPR011992. EF-hand-dom_pair.
IPR018247. EF_Hand_1_Ca_BS.
IPR002048. EF_hand_dom.
IPR029945. EHD2.
IPR000261. EPS15_homology.
IPR030381. G_DYNAMIN_dom.
IPR027417. P-loop_NTPase.
[Graphical view]
PANTHERiPTHR11216:SF62. PTHR11216:SF62. 1 hit.
SMARTiSM00027. EH. 1 hit.
[Graphical view]
SUPFAMiSSF52540. SSF52540. 1 hit.
PROSITEiPS00018. EF_HAND_1. 1 hit.
PS50222. EF_HAND_2. 1 hit.
PS50031. EH. 1 hit.
PS51718. G_DYNAMIN_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Q8BH64-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MFSWLKKGGA RGQRPEAIRT VTSSLKELYR TKLLPLEEHY RFGSFHSPAL
60 70 80 90 100
EDADFDGKPM VLVAGQYSTG KTSFIQYLLE QEVPGSRVGP EPTTDCFVAV
110 120 130 140 150
MHGETEGTVP GNALVVDPEK PFRKLNPFGN TFLNRFMCAQ LPNQVLESIS
160 170 180 190 200
IIDTPGILSG AKQRVSRGYD FPAVLRWFAE RVDLIILLFD AHKLEISDEF
210 220 230 240 250
SEAIGALRGH EDKIRVVLNK ADMVETQQLM RVYGALMWAL GKVVGTPEVL
260 270 280 290 300
RVYIGSFWSQ PLLVPDNRRL FELEEQDLFR DIQGLPRHAA LRKLNDLVKR
310 320 330 340 350
ARLVRVHAYI ISYLKKEMPT VFGKENKKKQ LILKLPVIFA KIQLEHHISP
360 370 380 390 400
GDFPDCQKMQ ELLMAHDFTK FHSLKPKLLE ALDDMLAQDI AKLMPLLRQE
410 420 430 440 450
ELESVEAGVQ GGAFEGTRMG PFVERGPDEA IEDGEEGSED DAEWVVTKDK
460 470 480 490 500
SKYDEIFYNL APADGKLSGS KAKTWMVGTK LPNSVLGRIW KLSDVDRDGM
510 520 530 540
LDDEEFALAS HLIEAKLEGH GLPTNLPRRL VPPSKRRQKG SAE
Length:543
Mass (Da):61,174
Last modified:March 1, 2003 - v1
Checksum:i47637795B0B1096E
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti181 – 1811R → S in BAC32789 (PubMed:16141072).Curated

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY531389 mRNA. Translation: AAS48536.1.
AK031203 mRNA. Translation: BAC27298.1.
AK046566 mRNA. Translation: BAC32789.1.
AK048356 mRNA. Translation: BAC33310.1.
AK050243 mRNA. Translation: BAC34142.1.
AK084455 mRNA. Translation: BAC39188.1.
AK085016 mRNA. Translation: BAC39339.1.
BC113161 mRNA. Translation: AAI13162.1.
CCDSiCCDS20842.1.
RefSeqiNP_694708.2. NM_153068.3.
XP_011248884.1. XM_011250582.1.
UniGeneiMm.138215.
Mm.438817.

Genome annotation databases

EnsembliENSMUST00000098799; ENSMUSP00000096397; ENSMUSG00000074364.
GeneIDi259300.
KEGGimmu:259300.
UCSCiuc009fgt.1. mouse.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY531389 mRNA. Translation: AAS48536.1.
AK031203 mRNA. Translation: BAC27298.1.
AK046566 mRNA. Translation: BAC32789.1.
AK048356 mRNA. Translation: BAC33310.1.
AK050243 mRNA. Translation: BAC34142.1.
AK084455 mRNA. Translation: BAC39188.1.
AK085016 mRNA. Translation: BAC39339.1.
BC113161 mRNA. Translation: AAI13162.1.
CCDSiCCDS20842.1.
RefSeqiNP_694708.2. NM_153068.3.
XP_011248884.1. XM_011250582.1.
UniGeneiMm.138215.
Mm.438817.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
2QPTX-ray3.10A1-543[»]
4CIDX-ray3.00A5-543[»]
ProteinModelPortaliQ8BH64.
SMRiQ8BH64. Positions 1-539.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

DIPiDIP-46806N.
IntActiQ8BH64. 2 interactions.
STRINGi10090.ENSMUSP00000096397.

PTM databases

PhosphoSiteiQ8BH64.

Proteomic databases

MaxQBiQ8BH64.
PaxDbiQ8BH64.
PRIDEiQ8BH64.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSMUST00000098799; ENSMUSP00000096397; ENSMUSG00000074364.
GeneIDi259300.
KEGGimmu:259300.
UCSCiuc009fgt.1. mouse.

Organism-specific databases

CTDi30846.
MGIiMGI:2154274. Ehd2.

Phylogenomic databases

eggNOGiNOG136252.
GeneTreeiENSGT00760000118985.
HOGENOMiHOG000242040.
HOVERGENiHBG018183.
InParanoidiQ8BH64.
KOiK12469.
OMAiMQEMLMA.
OrthoDBiEOG757CX9.
PhylomeDBiQ8BH64.
TreeFamiTF314429.

Enzyme and pathway databases

ReactomeiREACT_280010. Factors involved in megakaryocyte development and platelet production.

Miscellaneous databases

EvolutionaryTraceiQ8BH64.
NextBioi392043.
PROiQ8BH64.
SOURCEiSearch...

Gene expression databases

BgeeiQ8BH64.
CleanExiMM_EHD2.
ExpressionAtlasiQ8BH64. baseline and differential.
GenevisibleiQ8BH64. MM.

Family and domain databases

Gene3Di1.10.238.10. 1 hit.
3.40.50.300. 2 hits.
InterProiIPR011992. EF-hand-dom_pair.
IPR018247. EF_Hand_1_Ca_BS.
IPR002048. EF_hand_dom.
IPR029945. EHD2.
IPR000261. EPS15_homology.
IPR030381. G_DYNAMIN_dom.
IPR027417. P-loop_NTPase.
[Graphical view]
PANTHERiPTHR11216:SF62. PTHR11216:SF62. 1 hit.
SMARTiSM00027. EH. 1 hit.
[Graphical view]
SUPFAMiSSF52540. SSF52540. 1 hit.
PROSITEiPS00018. EF_HAND_1. 1 hit.
PS50222. EF_HAND_2. 1 hit.
PS50031. EH. 1 hit.
PS51718. G_DYNAMIN_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "EHD2 and the novel EH domain binding protein EHBP1 couple endocytosis to the actin cytoskeleton."
    Guilherme A., Soriano N.A., Bose S., Holik J., Bose A., Pomerleau D.P., Furcinitti P., Leszyk J., Corvera S., Czech M.P.
    J. Biol. Chem. 279:10593-10605(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, INTERACTION WITH EHBP1, SUBCELLULAR LOCATION, IDENTIFICATION BY MASS SPECTROMETRY, TISSUE SPECIFICITY.
    Strain: C57BL/6.
  2. "The transcriptional landscape of the mammalian genome."
    Carninci P., Kasukawa T., Katayama S., Gough J., Frith M.C., Maeda N., Oyama R., Ravasi T., Lenhard B., Wells C., Kodzius R., Shimokawa K., Bajic V.B., Brenner S.E., Batalov S., Forrest A.R., Zavolan M., Davis M.J.
    , Wilming L.G., Aidinis V., Allen J.E., Ambesi-Impiombato A., Apweiler R., Aturaliya R.N., Bailey T.L., Bansal M., Baxter L., Beisel K.W., Bersano T., Bono H., Chalk A.M., Chiu K.P., Choudhary V., Christoffels A., Clutterbuck D.R., Crowe M.L., Dalla E., Dalrymple B.P., de Bono B., Della Gatta G., di Bernardo D., Down T., Engstrom P., Fagiolini M., Faulkner G., Fletcher C.F., Fukushima T., Furuno M., Futaki S., Gariboldi M., Georgii-Hemming P., Gingeras T.R., Gojobori T., Green R.E., Gustincich S., Harbers M., Hayashi Y., Hensch T.K., Hirokawa N., Hill D., Huminiecki L., Iacono M., Ikeo K., Iwama A., Ishikawa T., Jakt M., Kanapin A., Katoh M., Kawasawa Y., Kelso J., Kitamura H., Kitano H., Kollias G., Krishnan S.P., Kruger A., Kummerfeld S.K., Kurochkin I.V., Lareau L.F., Lazarevic D., Lipovich L., Liu J., Liuni S., McWilliam S., Madan Babu M., Madera M., Marchionni L., Matsuda H., Matsuzawa S., Miki H., Mignone F., Miyake S., Morris K., Mottagui-Tabar S., Mulder N., Nakano N., Nakauchi H., Ng P., Nilsson R., Nishiguchi S., Nishikawa S., Nori F., Ohara O., Okazaki Y., Orlando V., Pang K.C., Pavan W.J., Pavesi G., Pesole G., Petrovsky N., Piazza S., Reed J., Reid J.F., Ring B.Z., Ringwald M., Rost B., Ruan Y., Salzberg S.L., Sandelin A., Schneider C., Schoenbach C., Sekiguchi K., Semple C.A., Seno S., Sessa L., Sheng Y., Shibata Y., Shimada H., Shimada K., Silva D., Sinclair B., Sperling S., Stupka E., Sugiura K., Sultana R., Takenaka Y., Taki K., Tammoja K., Tan S.L., Tang S., Taylor M.S., Tegner J., Teichmann S.A., Ueda H.R., van Nimwegen E., Verardo R., Wei C.L., Yagi K., Yamanishi H., Zabarovsky E., Zhu S., Zimmer A., Hide W., Bult C., Grimmond S.M., Teasdale R.D., Liu E.T., Brusic V., Quackenbush J., Wahlestedt C., Mattick J.S., Hume D.A., Kai C., Sasaki D., Tomaru Y., Fukuda S., Kanamori-Katayama M., Suzuki M., Aoki J., Arakawa T., Iida J., Imamura K., Itoh M., Kato T., Kawaji H., Kawagashira N., Kawashima T., Kojima M., Kondo S., Konno H., Nakano K., Ninomiya N., Nishio T., Okada M., Plessy C., Shibata K., Shiraki T., Suzuki S., Tagami M., Waki K., Watahiki A., Okamura-Oho Y., Suzuki H., Kawai J., Hayashizaki Y.
    Science 309:1559-1563(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Strain: C57BL/6J.
    Tissue: Adipose tissue, Embryonic eye, Embryonic head, Embryonic lung, Forelimb and Liver.
  3. "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].
  4. Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-438, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Embryonic brain.
  5. "The endocytic recycling protein EHD2 interacts with myoferlin to regulate myoblast fusion."
    Doherty K.R., Demonbreun A.R., Wallace G.Q., Cave A., Posey A.D., Heretis K., Pytel P., McNally E.M.
    J. Biol. Chem. 283:20252-20260(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, INTERACTION WITH MYOF, MUTAGENESIS OF GLY-65, IDENTIFICATION BY MASS SPECTROMETRY, SUBCELLULAR LOCATION.
  6. "Large scale localization of protein phosphorylation by use of electron capture dissociation mass spectrometry."
    Sweet S.M., Bailey C.M., Cunningham D.L., Heath J.K., Cooper H.J.
    Mol. Cell. Proteomics 8:904-912(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-438, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Embryonic fibroblast.
  7. "Endocytic recycling proteins EHD1 and EHD2 interact with fer-1-like-5 (Fer1L5) and mediate myoblast fusion."
    Posey A.D. Jr., Pytel P., Gardikiotes K., Demonbreun A.R., Rainey M., George M., Band H., McNally E.M.
    J. Biol. Chem. 286:7379-7388(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, INTERACTION WITH FER1L5 AND MYOF.
  8. "Architectural and mechanistic insights into an EHD ATPase involved in membrane remodelling."
    Daumke O., Lundmark R., Vallis Y., Martens S., Butler P.J.G., McMahon H.T.
    Nature 449:923-927(2007) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (3.1 ANGSTROMS) IN COMPLEX WITH ATP ANALOG AND CALCIUM IONS, SUBUNIT, SUBCELLULAR LOCATION, ENZYME REGULATION, MUTAGENESIS OF THR-72; THR-94; ILE-157; ARG-167; PHE-322; LYS-324; LYS-327; LYS-328 AND LYS-329.

Entry informationi

Entry nameiEHD2_MOUSE
AccessioniPrimary (citable) accession number: Q8BH64
Secondary accession number(s): Q8BL28
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 18, 2008
Last sequence update: March 1, 2003
Last modified: July 22, 2015
This is version 125 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. MGD cross-references
    Mouse Genome Database (MGD) cross-references in UniProtKB/Swiss-Prot
  2. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  3. 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.