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Protein

Solute carrier family 25 member 46

Gene

SLC25A46

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

Functioni

May play a role in mitochondrial dynamics by controlling mitochondrial membrane fission.1 Publication

GO - Biological processi

  • mitochondrial membrane fission Source: UniProtKB
  • transport Source: UniProtKB-KW
Complete GO annotation...

Keywords - Biological processi

Transport

Protein family/group databases

TCDBi2.A.29.30.1. the mitochondrial carrier (mc) family.

Names & Taxonomyi

Protein namesi
Recommended name:
Solute carrier family 25 member 46
Gene namesi
Name:SLC25A46
Synonyms:TB1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 5

Organism-specific databases

HGNCiHGNC:25198. SLC25A46.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Transmembranei103 – 12321Helical; Name=1Sequence analysisAdd
BLAST
Transmembranei167 – 18721Helical; Name=2Sequence analysisAdd
BLAST
Transmembranei202 – 22221Helical; Name=3Sequence analysisAdd
BLAST
Transmembranei258 – 27821Helical; Name=4Sequence analysisAdd
BLAST
Transmembranei314 – 33421Helical; Name=5Sequence analysisAdd
BLAST
Transmembranei382 – 40221Helical; Name=6Sequence analysisAdd
BLAST

GO - Cellular componenti

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

Keywords - Cellular componenti

Membrane, Mitochondrion, Mitochondrion outer membrane

Pathology & Biotechi

Involvement in diseasei

Neuropathy, hereditary motor and sensory, 6B (HMSN6B)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionAn autosomal recessive neurologic disorder characterized by early-onset optic atrophy, progressive visual loss, and peripheral sensorimotor neuropathy manifesting as axonal Charcot-Marie-Tooth disease, with variable age at onset and severity. Charcot-Marie-Tooth disease is a disorder of the peripheral nervous system, characterized by progressive weakness and atrophy, initially of the peroneal muscles and later of the distal muscles of the arms. It is classified in two main groups on the basis of electrophysiologic properties and histopathology: primary peripheral demyelinating neuropathies and primary peripheral axonal neuropathies. Peripheral axonal neuropathies are characterized by signs of axonal regeneration in the absence of obvious myelin alterations, and normal or slightly reduced nerve conduction velocities.
See also OMIM:616505
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti249 – 2491G → D in HMSN6B. 1 Publication
Corresponds to variant rs200725073 [ dbSNP | Ensembl ].
VAR_075818
Natural varianti333 – 3331P → L in HMSN6B. 1 Publication
VAR_075819
Natural varianti335 – 3351E → D in HMSN6B. 1 Publication
VAR_075820
Natural varianti340 – 3401R → C in HMSN6B. 1 Publication
Corresponds to variant rs746681765 [ dbSNP | Ensembl ].
VAR_075821

Keywords - Diseasei

Charcot-Marie-Tooth disease, Disease mutation, Neurodegeneration, Neuropathy

Organism-specific databases

MIMi616505. phenotype.
PharmGKBiPA162403737.

Polymorphism and mutation databases

BioMutaiSLC25A46.
DMDMi74751740.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 418418Solute carrier family 25 member 46PRO_0000291828Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei32 – 321PhosphoserineBy similarity
Modified residuei45 – 451PhosphothreonineCombined sources

Keywords - PTMi

Phosphoprotein

Proteomic databases

EPDiQ96AG3.
MaxQBiQ96AG3.
PaxDbiQ96AG3.
PeptideAtlasiQ96AG3.
PRIDEiQ96AG3.

PTM databases

iPTMnetiQ96AG3.
PhosphoSiteiQ96AG3.

Miscellaneous databases

PMAP-CutDBQ96AG3.

Expressioni

Gene expression databases

BgeeiQ96AG3.
CleanExiHS_SLC25A46.
ExpressionAtlasiQ96AG3. baseline and differential.
GenevisibleiQ96AG3. HS.

Interactioni

Subunit structurei

Interacts with IMMT.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
FHL3Q136433EBI-10281975,EBI-741101
FUNDC1Q8IVP53EBI-10281975,EBI-3059266

Protein-protein interaction databases

BioGridi124798. 22 interactions.
IntActiQ96AG3. 2 interactions.
STRINGi9606.ENSP00000348211.

Structurei

3D structure databases

ProteinModelPortaliQ96AG3.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Repeati96 – 18792Solcar 1Add
BLAST
Repeati311 – 413103Solcar 2Add
BLAST

Sequence similaritiesi

Contains 2 Solcar repeats.PROSITE-ProRule annotation

Keywords - Domaini

Repeat, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG2954. Eukaryota.
ENOG410XRFB. LUCA.
GeneTreeiENSGT00390000015874.
HOGENOMiHOG000007981.
HOVERGENiHBG059752.
InParanoidiQ96AG3.
KOiK03454.
OMAiTSWPKDV.
PhylomeDBiQ96AG3.
TreeFamiTF313365.

Family and domain databases

Gene3Di1.50.40.10. 1 hit.
InterProiIPR018108. Mitochondrial_sb/sol_carrier.
IPR023395. Mt_carrier_dom.
[Graphical view]
PfamiPF00153. Mito_carr. 1 hit.
[Graphical view]
SUPFAMiSSF103506. SSF103506. 1 hit.
PROSITEiPS50920. SOLCAR. 1 hit.
[Graphical view]

Sequences (3)i

Sequence statusi: Complete.

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

Isoform 1 (identifier: Q96AG3-1) [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
MHPRRPDGFD GLGYRGGARD EQGFGGAFPA RSFSTGSDLG HWVTTPPDIP
60 70 80 90 100
GSRNLHWGEK SPPYGVPTTS TPYEGPTEEP FSSGGGGSVQ GQSSEQLNRF
110 120 130 140 150
AGFGIGLASL FTENVLAHPC IVLRRQCQVN YHAQHYHLTP FTVINIMYSF
160 170 180 190 200
NKTQGPRALW KGMGSTFIVQ GVTLGAEGII SEFTPLPREV LHKWSPKQIG
210 220 230 240 250
EHLLLKSLTY VVAMPFYSAS LIETVQSEII RDNTGILECV KEGIGRVIGM
260 270 280 290 300
GVPHSKRLLP LLSLIFPTVL HGVLHYIISS VIQKFVLLIL KRKTYNSHLA
310 320 330 340 350
ESTSPVQSML DAYFPELIAN FAASLCSDVI LYPLETVLHR LHIQGTRTII
360 370 380 390 400
DNTDLGYEVL PINTQYEGMR DCINTIRQEE GVFGFYKGFG AVIIQYTLHA
410
AVLQITKIIY STLLQNNI
Length:418
Mass (Da):46,174
Last modified:December 1, 2001 - v1
Checksum:i97341574207816AB
GO
Isoform 2 (identifier: Q96AG3-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-146: Missing.

Note: No experimental confirmation available.
Show »
Length:272
Mass (Da):30,437
Checksum:iC430A54915A3DBDF
GO
Isoform 3 (identifier: Q96AG3-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     225-305: Missing.

Note: No experimental confirmation available.
Show »
Length:337
Mass (Da):37,203
Checksum:i01294E11A2C317BC
GO

Sequence cautioni

The sequence AAA03587.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti249 – 2491G → D in HMSN6B. 1 Publication
Corresponds to variant rs200725073 [ dbSNP | Ensembl ].
VAR_075818
Natural varianti333 – 3331P → L in HMSN6B. 1 Publication
VAR_075819
Natural varianti335 – 3351E → D in HMSN6B. 1 Publication
VAR_075820
Natural varianti340 – 3401R → C in HMSN6B. 1 Publication
Corresponds to variant rs746681765 [ dbSNP | Ensembl ].
VAR_075821

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 146146Missing in isoform 2. 1 PublicationVSP_056112Add
BLAST
Alternative sequencei225 – 30581Missing in isoform 3. 1 PublicationVSP_056351Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M74089 mRNA. Translation: AAA03587.1. Different initiation.
AK091427 mRNA. Translation: BAG52358.1.
AK290217 mRNA. Translation: BAF82906.1.
AK300123 mRNA. Translation: BAG61915.1.
AC008650 Genomic DNA. No translation available.
CH471086 Genomic DNA. Translation: EAW49040.1.
CH471086 Genomic DNA. Translation: EAW49041.1.
BC017169 mRNA. Translation: AAH17169.1.
CCDSiCCDS4100.1. [Q96AG3-1]
CCDS78045.1. [Q96AG3-3]
RefSeqiNP_001290178.1. NM_001303249.1. [Q96AG3-3]
NP_001290179.1. NM_001303250.1.
NP_620128.1. NM_138773.2. [Q96AG3-1]
UniGeneiHs.75639.

Genome annotation databases

EnsembliENST00000355943; ENSP00000348211; ENSG00000164209. [Q96AG3-1]
ENST00000447245; ENSP00000399717; ENSG00000164209. [Q96AG3-3]
ENST00000504098; ENSP00000425708; ENSG00000164209. [Q96AG3-2]
GeneIDi91137.
KEGGihsa:91137.
UCSCiuc003koz.5. human. [Q96AG3-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M74089 mRNA. Translation: AAA03587.1. Different initiation.
AK091427 mRNA. Translation: BAG52358.1.
AK290217 mRNA. Translation: BAF82906.1.
AK300123 mRNA. Translation: BAG61915.1.
AC008650 Genomic DNA. No translation available.
CH471086 Genomic DNA. Translation: EAW49040.1.
CH471086 Genomic DNA. Translation: EAW49041.1.
BC017169 mRNA. Translation: AAH17169.1.
CCDSiCCDS4100.1. [Q96AG3-1]
CCDS78045.1. [Q96AG3-3]
RefSeqiNP_001290178.1. NM_001303249.1. [Q96AG3-3]
NP_001290179.1. NM_001303250.1.
NP_620128.1. NM_138773.2. [Q96AG3-1]
UniGeneiHs.75639.

3D structure databases

ProteinModelPortaliQ96AG3.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi124798. 22 interactions.
IntActiQ96AG3. 2 interactions.
STRINGi9606.ENSP00000348211.

Protein family/group databases

TCDBi2.A.29.30.1. the mitochondrial carrier (mc) family.

PTM databases

iPTMnetiQ96AG3.
PhosphoSiteiQ96AG3.

Polymorphism and mutation databases

BioMutaiSLC25A46.
DMDMi74751740.

Proteomic databases

EPDiQ96AG3.
MaxQBiQ96AG3.
PaxDbiQ96AG3.
PeptideAtlasiQ96AG3.
PRIDEiQ96AG3.

Protocols and materials databases

DNASUi91137.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000355943; ENSP00000348211; ENSG00000164209. [Q96AG3-1]
ENST00000447245; ENSP00000399717; ENSG00000164209. [Q96AG3-3]
ENST00000504098; ENSP00000425708; ENSG00000164209. [Q96AG3-2]
GeneIDi91137.
KEGGihsa:91137.
UCSCiuc003koz.5. human. [Q96AG3-1]

Organism-specific databases

CTDi91137.
GeneCardsiSLC25A46.
H-InvDBHIX0005077.
HGNCiHGNC:25198. SLC25A46.
MIMi610826. gene.
616505. phenotype.
neXtProtiNX_Q96AG3.
PharmGKBiPA162403737.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG2954. Eukaryota.
ENOG410XRFB. LUCA.
GeneTreeiENSGT00390000015874.
HOGENOMiHOG000007981.
HOVERGENiHBG059752.
InParanoidiQ96AG3.
KOiK03454.
OMAiTSWPKDV.
PhylomeDBiQ96AG3.
TreeFamiTF313365.

Miscellaneous databases

ChiTaRSiSLC25A46. human.
GenomeRNAii91137.
PMAP-CutDBQ96AG3.
PROiQ96AG3.
SOURCEiSearch...

Gene expression databases

BgeeiQ96AG3.
CleanExiHS_SLC25A46.
ExpressionAtlasiQ96AG3. baseline and differential.
GenevisibleiQ96AG3. HS.

Family and domain databases

Gene3Di1.50.40.10. 1 hit.
InterProiIPR018108. Mitochondrial_sb/sol_carrier.
IPR023395. Mt_carrier_dom.
[Graphical view]
PfamiPF00153. Mito_carr. 1 hit.
[Graphical view]
SUPFAMiSSF103506. SSF103506. 1 hit.
PROSITEiPS50920. SOLCAR. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. Cited for: NUCLEOTIDE SEQUENCE [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] (ISOFORMS 1; 2 AND 3).
    Tissue: Brain, Placenta and Thalamus.
  3. "The DNA sequence and comparative analysis of human chromosome 5."
    Schmutz J., Martin J., Terry A., Couronne O., Grimwood J., Lowry S., Gordon L.A., Scott D., Xie G., Huang W., Hellsten U., Tran-Gyamfi M., She X., Prabhakar S., Aerts A., Altherr M., Bajorek E., Black S.
    , Branscomb E., Caoile C., Challacombe J.F., Chan Y.M., Denys M., Detter J.C., Escobar J., Flowers D., Fotopulos D., Glavina T., Gomez M., Gonzales E., Goodstein D., Grigoriev I., Groza M., Hammon N., Hawkins T., Haydu L., Israni S., Jett J., Kadner K., Kimball H., Kobayashi A., Lopez F., Lou Y., Martinez D., Medina C., Morgan J., Nandkeshwar R., Noonan J.P., Pitluck S., Pollard M., Predki P., Priest J., Ramirez L., Retterer J., Rodriguez A., Rogers S., Salamov A., Salazar A., Thayer N., Tice H., Tsai M., Ustaszewska A., Vo N., Wheeler J., Wu K., Yang J., Dickson M., Cheng J.-F., Eichler E.E., Olsen A., Pennacchio L.A., Rokhsar D.S., Richardson P., Lucas S.M., Myers R.M., Rubin E.M.
    Nature 431:268-274(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  4. 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] (ISOFORM 1).
    Tissue: Skin.
  6. "Fourteen novel human members of mitochondrial solute carrier family 25 (SLC25) widely expressed in the central nervous system."
    Haitina T., Lindblom J., Renstroem T., Fredriksson R.
    Genomics 88:779-790(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION.
  7. "Kinase-selective enrichment enables quantitative phosphoproteomics of the kinome across the cell cycle."
    Daub H., Olsen J.V., Bairlein M., Gnad F., Oppermann F.S., Korner R., Greff Z., Keri G., Stemmann O., Mann M.
    Mol. Cell 31:438-448(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  8. Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT THR-45, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Cervix carcinoma.
  9. "Quantitative phosphoproteomic analysis of T cell receptor signaling reveals system-wide modulation of protein-protein interactions."
    Mayya V., Lundgren D.H., Hwang S.-I., Rezaul K., Wu L., Eng J.K., Rodionov V., Han D.K.
    Sci. Signal. 2:RA46-RA46(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Leukemic T-cell.
  10. "Toward a comprehensive characterization of a human cancer cell phosphoproteome."
    Zhou H., Di Palma S., Preisinger C., Peng M., Polat A.N., Heck A.J., Mohammed S.
    J. Proteome Res. 12:260-271(2013) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Erythroleukemia.
  11. "An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
    Bian Y., Song C., Cheng K., Dong M., Wang F., Huang J., Sun D., Wang L., Ye M., Zou H.
    J. Proteomics 96:253-262(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT THR-45, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Liver.
  12. Cited for: FUNCTION, SUBCELLULAR LOCATION, INTERACTION WITH IMMT, INVOLVEMENT IN HMSN6B, VARIANTS HMSN6B ASP-249; LEU-333; ASP-335 AND CYS-340.

Entry informationi

Entry nameiS2546_HUMAN
AccessioniPrimary (citable) accession number: Q96AG3
Secondary accession number(s): A8K2F2
, B3KRE6, B4DTA3, D3DSZ6, D6R9W7, Q04197
Entry historyi
Integrated into UniProtKB/Swiss-Prot: June 26, 2007
Last sequence update: December 1, 2001
Last modified: July 6, 2016
This is version 114 of the entry and version 1 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 5
    Human chromosome 5: 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. 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.