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Protein

Kelch-like protein 40

Gene

KLHL40

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

Functioni

Required for skeletal muscle development.1 Publication

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Developmental protein

Names & Taxonomyi

Protein namesi
Recommended name:
Kelch-like protein 40
Alternative name(s):
Kelch repeat and BTB domain-containing protein 5
Sarcosynapsin
Gene namesi
Name:KLHL40
Synonyms:KBTBD5, SRYP
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 3

Organism-specific databases

HGNCiHGNC:30372. KLHL40.

Subcellular locationi

GO - Cellular componenti

  • A band Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm

Pathology & Biotechi

Involvement in diseasei

Nemaline myopathy 8 (NEM8)1 Publication

The disease is caused by mutations affecting the gene represented in this entry.

Disease descriptionA severe form of nemaline myopathy. Nemaline myopathies are muscular disorders characterized by muscle weakness of varying severity and onset, and abnormal thread-like or rod-shaped structures in muscle fibers on histologic examination. NEM8 is characterized by fetal akinesia or hypokinesia, followed by contractures, fractures, respiratory failure, and swallowing difficulties apparent at birth. Most patients die in infancy. Skeletal muscle biopsy shows numerous small nemaline bodies, often with no normal myofibrils.

See also OMIM:615348
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti34 – 341D → H in NEM8. 1 Publication
VAR_069836
Natural varianti86 – 861L → P in NEM8. 1 Publication
VAR_069837
Natural varianti194 – 1941V → E in NEM8. 1 Publication
VAR_069838
Natural varianti201 – 2011W → L in NEM8. 1 Publication
VAR_069839
Natural varianti311 – 3111R → L in NEM8. 1 Publication
VAR_069840
Natural varianti397 – 3971P → L in NEM8. 1 Publication
VAR_069841
Natural varianti455 – 4551H → R in NEM8. 1 Publication
VAR_069842
Natural varianti469 – 4691G → C in NEM8. 1 Publication
VAR_069843
Natural varianti506 – 5061T → P in NEM8. 1 Publication
VAR_069844
Natural varianti528 – 5281E → K in NEM8. 1 Publication
VAR_069845
Natural varianti538 – 5381A → P in NEM8. 1 Publication
VAR_069846
Natural varianti588 – 5881E → K in NEM8. 1 Publication
VAR_069847

Keywords - Diseasei

Disease mutation, Nemaline myopathy

Organism-specific databases

MIMi615348. phenotype.
Orphaneti171430. Severe congenital nemaline myopathy.
PharmGKBiPA134908127.

Polymorphism and mutation databases

DMDMi125950763.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 621621Kelch-like protein 40PRO_0000274235Add
BLAST

Proteomic databases

PaxDbiQ2TBA0.
PRIDEiQ2TBA0.

PTM databases

PhosphoSiteiQ2TBA0.

Expressioni

Tissue specificityi

Highly expressed in fetal (19, 23 and 31 weeks of gestation) and adult skeletal muscle; expression levels tend to be higher in fetal compared to postnatal muscles (at protein level). Aslo expressed in fetal and adult heart.1 Publication

Gene expression databases

BgeeiQ2TBA0.
CleanExiHS_KBTBD5.
GenevisibleiQ2TBA0. HS.

Organism-specific databases

HPAiHPA024463.
HPA052201.

Interactioni

Protein-protein interaction databases

BioGridi126278. 41 interactions.
IntActiQ2TBA0. 1 interaction.
MINTiMINT-8330030.
STRINGi9606.ENSP00000287777.

Structurei

Secondary structure

1
621
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi317 – 3248Combined sources
Beta strandi327 – 3326Combined sources
Turni333 – 3364Combined sources
Beta strandi337 – 3426Combined sources
Beta strandi349 – 3557Combined sources
Beta strandi361 – 3699Combined sources
Beta strandi374 – 3763Combined sources
Beta strandi378 – 3869Combined sources
Turni387 – 3904Combined sources
Beta strandi391 – 3944Combined sources
Beta strandi398 – 4003Combined sources
Beta strandi402 – 4043Combined sources
Beta strandi406 – 4105Combined sources
Beta strandi413 – 4175Combined sources
Beta strandi420 – 4234Combined sources
Beta strandi432 – 4365Combined sources
Turni437 – 4404Combined sources
Beta strandi441 – 4444Combined sources
Beta strandi456 – 4605Combined sources
Beta strandi463 – 4675Combined sources
Beta strandi480 – 4845Combined sources
Turni485 – 4884Combined sources
Beta strandi489 – 4924Combined sources
Beta strandi504 – 5085Combined sources
Beta strandi511 – 5188Combined sources
Beta strandi520 – 53112Combined sources
Turni532 – 5354Combined sources
Beta strandi536 – 5405Combined sources
Beta strandi551 – 5555Combined sources
Beta strandi558 – 56912Combined sources
Beta strandi575 – 58713Combined sources
Turni588 – 5914Combined sources
Beta strandi592 – 5987Combined sources
Beta strandi607 – 6137Combined sources
Helixi615 – 6173Combined sources
Beta strandi618 – 6203Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4ASCX-ray1.78A314-621[»]
ProteinModelPortaliQ2TBA0.
SMRiQ2TBA0. Positions 29-262, 314-621.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini33 – 9866BTBPROSITE-ProRule annotationAdd
BLAST
Domaini133 – 239107BACKAdd
BLAST
Repeati360 – 41253Kelch 1Add
BLAST
Repeati413 – 46250Kelch 2Add
BLAST
Repeati463 – 51048Kelch 3Add
BLAST
Repeati512 – 55746Kelch 4Add
BLAST
Repeati559 – 61355Kelch 5Add
BLAST

Compositional bias

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Compositional biasi270 – 2756Poly-Lys

Sequence similaritiesi

Contains 1 BTB (POZ) domain.PROSITE-ProRule annotation
Contains 5 Kelch repeats.Curated

Keywords - Domaini

Kelch repeat, Repeat

Phylogenomic databases

eggNOGiNOG290520.
GeneTreeiENSGT00790000122972.
HOGENOMiHOG000231966.
HOVERGENiHBG052215.
InParanoidiQ2TBA0.
KOiK10473.
OMAiELAPMKT.
OrthoDBiEOG7M6D6S.
PhylomeDBiQ2TBA0.
TreeFamiTF351653.

Family and domain databases

Gene3Di2.120.10.80. 1 hit.
InterProiIPR011705. BACK.
IPR017096. BTB-kelch_protein.
IPR000210. BTB/POZ-like.
IPR011333. BTB/POZ_fold.
IPR013069. BTB_POZ.
IPR015915. Kelch-typ_b-propeller.
IPR006652. Kelch_1.
IPR030607. KLHL40.
[Graphical view]
PANTHERiPTHR24412:SF22. PTHR24412:SF22. 1 hit.
PfamiPF07707. BACK. 1 hit.
PF00651. BTB. 1 hit.
PF01344. Kelch_1. 3 hits.
[Graphical view]
PIRSFiPIRSF037037. Kelch-like_protein_gigaxonin. 1 hit.
SMARTiSM00875. BACK. 1 hit.
SM00225. BTB. 1 hit.
SM00612. Kelch. 4 hits.
[Graphical view]
SUPFAMiSSF54695. SSF54695. 1 hit.
PROSITEiPS50097. BTB. 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: Q2TBA0-1) [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
MALGLEQAEE QRLYQQTLLQ DGLKDMLDHG KFLDCVVRAG EREFPCHRLV
60 70 80 90 100
LAACSPYFRA RFLAEPERAG ELHLEEVSPD VVAQVLHYLY TSEIALDEAS
110 120 130 140 150
VQDLFAAAHR FQIPSIFTIC VSFLQKRLCL SNCLAVFRLG LLLDCARLAV
160 170 180 190 200
AARDFICAHF TLVARDADFL GLSADELIAI ISSDGLNVEK EEAVFEAVMR
210 220 230 240 250
WAGSGDAEAQ AERQRALPTV FESVRCRLLP RAFLESRVER HPLVRAQPEL
260 270 280 290 300
LRKVQMVKDA HEGRITTLRK KKKGKDGAGA KEADKGTSKA KAEEDEEAER
310 320 330 340 350
ILPGILNDTL RFGMFLQDLI FMISEEGAVA YDPAANECYC ASLSNQVPKN
360 370 380 390 400
HVSLVTKENQ VFVAGGLFYN EDNKEDPMSA YFLQFDHLDS EWLGMPPLPS
410 420 430 440 450
PRCLFGLGEA LNSIYVVGGR EIKDGERCLD SVMCYDRLSF KWGESDPLPY
460 470 480 490 500
VVYGHTVLSH MDLVYVIGGK GSDRKCLNKM CVYDPKKFEW KELAPMQTAR
510 520 530 540 550
SLFGATVHDG RIIVAAGVTD TGLTSSAEVY SITDNKWAPF EAFPQERSSL
560 570 580 590 600
SLVSLVGTLY AIGGFATLET ESGELVPTEL NDIWRYNEEE KKWEGVLREI
610 620
AYAAGATFLP VRLNVLCLTK M
Length:621
Mass (Da):69,257
Last modified:February 6, 2007 - v2
Checksum:i53492478F08A5A2D
GO
Isoform 2 (identifier: Q2TBA0-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     444-604: ESDPLPYVVY...GVLREIAYAA → HRHRADQFCRSVQHHRQQVGTLRGLPTGA
     605-621: Missing.

Note: No experimental confirmation available.
Show »
Length:472
Mass (Da):52,893
Checksum:i6A64676A03325797
GO

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti34 – 341D → H in NEM8. 1 Publication
VAR_069836
Natural varianti86 – 861L → P in NEM8. 1 Publication
VAR_069837
Natural varianti194 – 1941V → E in NEM8. 1 Publication
VAR_069838
Natural varianti201 – 2011W → L in NEM8. 1 Publication
VAR_069839
Natural varianti311 – 3111R → L in NEM8. 1 Publication
VAR_069840
Natural varianti345 – 3451N → S.2 Publications
Corresponds to variant rs6805421 [ dbSNP | Ensembl ].
VAR_030214
Natural varianti397 – 3971P → L in NEM8. 1 Publication
VAR_069841
Natural varianti455 – 4551H → R in NEM8. 1 Publication
VAR_069842
Natural varianti469 – 4691G → C in NEM8. 1 Publication
VAR_069843
Natural varianti506 – 5061T → P in NEM8. 1 Publication
VAR_069844
Natural varianti528 – 5281E → K in NEM8. 1 Publication
VAR_069845
Natural varianti538 – 5381A → P in NEM8. 1 Publication
VAR_069846
Natural varianti588 – 5881E → K in NEM8. 1 Publication
VAR_069847
Natural varianti617 – 6171C → R.1 Publication
Corresponds to variant rs123509 [ dbSNP | Ensembl ].
VAR_030215

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei444 – 604161ESDPL…IAYAA → HRHRADQFCRSVQHHRQQVG TLRGLPTGA in isoform 2. 1 PublicationVSP_022681Add
BLAST
Alternative sequencei605 – 62117Missing in isoform 2. 1 PublicationVSP_022682Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY177390 mRNA. Translation: AAO06908.1.
AY176040 mRNA. Translation: AAO22141.1.
AK056577 mRNA. Translation: BAB71222.1.
BC110491 mRNA. Translation: AAI10492.1.
CCDSiCCDS2703.1. [Q2TBA0-1]
RefSeqiNP_689606.2. NM_152393.3. [Q2TBA0-1]
UniGeneiHs.350288.

Genome annotation databases

EnsembliENST00000287777; ENSP00000287777; ENSG00000157119. [Q2TBA0-1]
GeneIDi131377.
KEGGihsa:131377.
UCSCiuc003clv.1. human. [Q2TBA0-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AY177390 mRNA. Translation: AAO06908.1.
AY176040 mRNA. Translation: AAO22141.1.
AK056577 mRNA. Translation: BAB71222.1.
BC110491 mRNA. Translation: AAI10492.1.
CCDSiCCDS2703.1. [Q2TBA0-1]
RefSeqiNP_689606.2. NM_152393.3. [Q2TBA0-1]
UniGeneiHs.350288.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
4ASCX-ray1.78A314-621[»]
ProteinModelPortaliQ2TBA0.
SMRiQ2TBA0. Positions 29-262, 314-621.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi126278. 41 interactions.
IntActiQ2TBA0. 1 interaction.
MINTiMINT-8330030.
STRINGi9606.ENSP00000287777.

PTM databases

PhosphoSiteiQ2TBA0.

Polymorphism and mutation databases

DMDMi125950763.

Proteomic databases

PaxDbiQ2TBA0.
PRIDEiQ2TBA0.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000287777; ENSP00000287777; ENSG00000157119. [Q2TBA0-1]
GeneIDi131377.
KEGGihsa:131377.
UCSCiuc003clv.1. human. [Q2TBA0-1]

Organism-specific databases

CTDi131377.
GeneCardsiGC03P042727.
HGNCiHGNC:30372. KLHL40.
HPAiHPA024463.
HPA052201.
MIMi615340. gene.
615348. phenotype.
neXtProtiNX_Q2TBA0.
Orphaneti171430. Severe congenital nemaline myopathy.
PharmGKBiPA134908127.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG290520.
GeneTreeiENSGT00790000122972.
HOGENOMiHOG000231966.
HOVERGENiHBG052215.
InParanoidiQ2TBA0.
KOiK10473.
OMAiELAPMKT.
OrthoDBiEOG7M6D6S.
PhylomeDBiQ2TBA0.
TreeFamiTF351653.

Miscellaneous databases

GenomeRNAii131377.
NextBioi82900.
PROiQ2TBA0.
SOURCEiSearch...

Gene expression databases

BgeeiQ2TBA0.
CleanExiHS_KBTBD5.
GenevisibleiQ2TBA0. HS.

Family and domain databases

Gene3Di2.120.10.80. 1 hit.
InterProiIPR011705. BACK.
IPR017096. BTB-kelch_protein.
IPR000210. BTB/POZ-like.
IPR011333. BTB/POZ_fold.
IPR013069. BTB_POZ.
IPR015915. Kelch-typ_b-propeller.
IPR006652. Kelch_1.
IPR030607. KLHL40.
[Graphical view]
PANTHERiPTHR24412:SF22. PTHR24412:SF22. 1 hit.
PfamiPF07707. BACK. 1 hit.
PF00651. BTB. 1 hit.
PF01344. Kelch_1. 3 hits.
[Graphical view]
PIRSFiPIRSF037037. Kelch-like_protein_gigaxonin. 1 hit.
SMARTiSM00875. BACK. 1 hit.
SM00225. BTB. 1 hit.
SM00612. Kelch. 4 hits.
[Graphical view]
SUPFAMiSSF54695. SSF54695. 1 hit.
PROSITEiPS50097. BTB. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Structure, gene organization and expression analysis of human sarcosynapsin."
    Goudou D., Bitoun M., Rieger F., Perin J.-P., Alliel P.M.
    Submitted (NOV-2002) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ISOFORM 1).
    Tissue: Heart.
  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), VARIANT SER-345.
    Tissue: Tongue.
  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] (ISOFORM 1), VARIANTS SER-345 AND ARG-617.
  4. Cited for: X-RAY CRYSTALLOGRAPHY (1.78 ANGSTROMS) OF 314-621.
  5. "Mutations in KLHL40 are a frequent cause of severe autosomal-recessive nemaline myopathy."
    Ravenscroft G., Miyatake S., Lehtokari V.L., Todd E.J., Vornanen P., Yau K.S., Hayashi Y.K., Miyake N., Tsurusaki Y., Doi H., Saitsu H., Osaka H., Yamashita S., Ohya T., Sakamoto Y., Koshimizu E., Imamura S., Yamashita M.
    , Ogata K., Shiina M., Bryson-Richardson R.J., Vaz R., Ceyhan O., Brownstein C.A., Swanson L.C., Monnot S., Romero N.B., Amthor H., Kresoje N., Sivadorai P., Kiraly-Borri C., Haliloglu G., Talim B., Orhan D., Kale G., Charles A.K., Fabian V.A., Davis M.R., Lammens M., Sewry C.A., Manzur A., Muntoni F., Clarke N.F., North K.N., Bertini E., Nevo Y., Willichowski E., Silberg I.E., Topaloglu H., Beggs A.H., Allcock R.J., Nishino I., Wallgren-Pettersson C., Matsumoto N., Laing N.G.
    Am. J. Hum. Genet. 93:6-18(2013) [PubMed] [Europe PMC] [Abstract]
    Cited for: VARIANTS NEM8 HIS-34; PRO-86; GLU-194; LEU-201; LEU-311; LEU-397; ARG-455; CYS-469; PRO-506; LYS-528; PRO-538 AND LYS-588, FUNCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.

Entry informationi

Entry nameiKLH40_HUMAN
AccessioniPrimary (citable) accession number: Q2TBA0
Secondary accession number(s): Q86SI1, Q96MR2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: February 6, 2007
Last sequence update: February 6, 2007
Last modified: June 24, 2015
This is version 79 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 3
    Human chromosome 3: 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. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  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.