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Protein

Keratin-associated protein 10-9

Gene

KRTAP10-9

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

Functioni

In the hair cortex, hair keratin intermediate filaments are embedded in an interfilamentous matrix, consisting of hair keratin-associated proteins (KRTAP), which are essential for the formation of a rigid and resistant hair shaft through their extensive disulfide bond cross-linking with abundant cysteine residues of hair keratins. The matrix proteins include the high-sulfur and high-glycine-tyrosine keratins.

Names & Taxonomyi

Protein namesi
Recommended name:
Keratin-associated protein 10-9
Alternative name(s):
High sulfur keratin-associated protein 10.9
Keratin-associated protein 10.9
Keratin-associated protein 18-9
Keratin-associated protein 18.9
Gene namesi
Name:KRTAP10-9
Synonyms:KAP10.9, KAP18-9, KRTAP10.9, KRTAP18-9, KRTAP18.9
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componenti: Chromosome 21

Organism-specific databases

HGNCiHGNC:22971. KRTAP10-9.

Subcellular locationi

GO - Cellular componenti

  1. keratin filament Source: InterPro
Complete GO annotation...

Keywords - Cellular componenti

Keratin

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA134873081.

Polymorphism and mutation databases

BioMutaiKRTAP10-9.
DMDMi294862449.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 292292Keratin-associated protein 10-9PRO_0000185217Add
BLAST

Proteomic databases

PaxDbiP60411.
PeptideAtlasiP60411.
PRIDEiP60411.

PTM databases

PhosphoSiteiP60411.

Expressioni

Tissue specificityi

Restricted to a narrow region of the hair fiber cuticle, lying approximately 20 cell layers above the apex of the dermal papilla of the hair root; not detected in any other tissues.2 Publications

Gene expression databases

BgeeiP60411.
CleanExiHS_KRTAP10-9.
GenevestigatoriP60411.

Interactioni

Subunit structurei

Interacts with hair keratins.

Binary interactionsi

WithEntry#Exp.IntActNotes
A8K9323EBI-10172052,EBI-10174671
Q5XG853EBI-10172052,EBI-10248413
Q9H6F03EBI-10172052,EBI-10307481
Q9NWL93EBI-10172052,EBI-10315054
ADAMTSL4Q6UY14-33EBI-10172052,EBI-10173507
AESQ081173EBI-10172052,EBI-717810
ALDH3B1P433533EBI-10172052,EBI-2558314
ALPIP099233EBI-10172052,EBI-1052631
ARFGAP1Q8N6T33EBI-10172052,EBI-716933
ATXN7L1Q9ULK23EBI-10172052,EBI-310660
AVPI1Q5T6863EBI-10172052,EBI-8640233
BCL6BA8KA133EBI-10172052,EBI-10174813
C10orf62Q5T6813EBI-10172052,EBI-744052
C11orf87Q6NUJ23EBI-10172052,EBI-6660291
C16orf59Q7L2K03EBI-10172052,EBI-8465456
C19orf57Q0VDD73EBI-10172052,EBI-741210
C19orf66Q9NUL53EBI-10172052,EBI-10313866
C5orf60A6NFR6-43EBI-10172052,EBI-10173955
C9orf9Q96E403EBI-10172052,EBI-722584
CARKDQ8IW453EBI-10172052,EBI-8650724
CATIPQ7Z7H33EBI-10172052,EBI-10258233
CATSPER1Q8NEC55EBI-10172052,EBI-744545
CBX2Q147813EBI-10172052,EBI-745934
CCDC26Q8TAB73EBI-10172052,EBI-10271580
CD300LGQ6UXG33EBI-10172052,EBI-10254587
CDKL3Q8IVW43EBI-10172052,EBI-3919850
CHIC2Q9UKJ53EBI-10172052,EBI-741528
CHRDQ9H2X03EBI-10172052,EBI-947551
CHRNGP075103EBI-10172052,EBI-9008836
CKS1BP610243EBI-10172052,EBI-456371
CLK4Q9HAZ13EBI-10172052,EBI-633400
CNNM3Q8NE013EBI-10172052,EBI-741032
CNNM3Q8NE01-33EBI-10172052,EBI-10269984
CRCT1Q9UGL93EBI-10172052,EBI-713677
CREB5Q02930-33EBI-10172052,EBI-10192698
CST9LQ9H4G13EBI-10172052,EBI-3923092
DHX57Q6P1583EBI-10172052,EBI-1051531
DMRT3Q9NQL93EBI-10172052,EBI-9679045
DOCK2Q926083EBI-10172052,EBI-448771
EIF4E2O605733EBI-10172052,EBI-398610
FAM124BQ9H5Z63EBI-10172052,EBI-741626
FAM161AQ3B8203EBI-10172052,EBI-719941
FAM74A6Q5TZK33EBI-10172052,EBI-10247271
FAM76BQ5HYJ33EBI-10172052,EBI-751192
FARS2O953633EBI-10172052,EBI-2513774
GABARAPL1Q9H0R83EBI-10172052,EBI-3464833
GABARAPL2P605203EBI-10172052,EBI-720116
GATA2P237693EBI-10172052,EBI-2806671
GLP1RP432203EBI-10172052,EBI-7466542
GLRX3O760033EBI-10172052,EBI-374781
GNEQ9Y2233EBI-10172052,EBI-4291090
GPATCH2LQ9NWQ43EBI-10172052,EBI-5666657
GSTP1P092113EBI-10172052,EBI-353467
HBG2D9YZU93EBI-10172052,EBI-10176884
HBZP020083EBI-10172052,EBI-719843
HCKP086313EBI-10172052,EBI-346340
HOXA1P496395EBI-10172052,EBI-740785
HOXB9P174823EBI-10172052,EBI-745290
HPCAL1P372353EBI-10172052,EBI-749311
HSD3B7Q9H2F33EBI-10172052,EBI-3918847
IGSF8Q969P03EBI-10172052,EBI-8293590
INPP5DQ928353EBI-10172052,EBI-1380477
IQUBQ8NA543EBI-10172052,EBI-10220600
ITGB5L7RT223EBI-10172052,EBI-10178729
KAT5Q929933EBI-10172052,EBI-399080
KLHL38Q2WGJ63EBI-10172052,EBI-6426443
KRT20P359003EBI-10172052,EBI-742094
KRT83P783853EBI-10172052,EBI-10221390
KRTAP10-7P604093EBI-10172052,EBI-10172290
KRTAP10-8P604103EBI-10172052,EBI-10171774
KRTAP12-1P599903EBI-10172052,EBI-10210845
KRTAP26-1Q6PEX33EBI-10172052,EBI-3957672
KRTAP4-11Q9BYQ63EBI-10172052,EBI-10302392
KRTAP4-12Q9BQ663EBI-10172052,EBI-739863
KRTAP4-2Q9BYR55EBI-10172052,EBI-10172511
KRTAP5-6Q6L8G93EBI-10172052,EBI-10250562
KRTAP5-9P263713EBI-10172052,EBI-3958099
KRTAP9-2Q9BYQ46EBI-10172052,EBI-1044640
KRTAP9-4Q9BYQ23EBI-10172052,EBI-10185730
LCE1BQ5T7P33EBI-10172052,EBI-10245913
LCE2AQ5TA793EBI-10172052,EBI-10246607
LCE2DQ5TA823EBI-10172052,EBI-10246750
LCE3CQ5T5A83EBI-10172052,EBI-10245291
LCE3EQ5T5B04EBI-10172052,EBI-10245456
LCE4AQ5TA783EBI-10172052,EBI-10246358
LUZP4Q9P1273EBI-10172052,EBI-10198848
MAB21L3Q8N8X93EBI-10172052,EBI-10268010
MAPKBP1O603363EBI-10172052,EBI-947402
MED30Q96HR33EBI-10172052,EBI-394659
MEOX2A4D1274EBI-10172052,EBI-10172134
MOBPQ138753EBI-10172052,EBI-10230628
MT1DPA1L3X43EBI-10172052,EBI-10172129
MXI1P50539-33EBI-10172052,EBI-10211940
NOTCH2NLQ7Z3S93EBI-10172052,EBI-945833
NPBWR2P481463EBI-10172052,EBI-10210114
NPDC1Q9NQX53EBI-10172052,EBI-748927
NPPBP168603EBI-10172052,EBI-747044
NR1D2Q6NSM04EBI-10172052,EBI-10250949
NUFIP2A1L3A75EBI-10172052,EBI-10172018
OTX1P322426EBI-10172052,EBI-740446
PGAP2Q9UHJ93EBI-10172052,EBI-10321427
PIN1Q135263EBI-10172052,EBI-714158
PLSCR1O151623EBI-10172052,EBI-740019
PRKAB2O437413EBI-10172052,EBI-1053424
PRPF31F1T0A53EBI-10172052,EBI-10177194
PTGER3Q147X83EBI-10172052,EBI-10234038
PVRP151513EBI-10172052,EBI-3919694
PVRL3Q9NQS33EBI-10172052,EBI-2826725
RHNO1Q9BSD33EBI-10172052,EBI-9658624
RSPO2Q6UXX93EBI-10172052,EBI-8481036
SCARB1Q8WTV03EBI-10172052,EBI-78657
SCNM1Q9BWG63EBI-10172052,EBI-748391
SLC23A1Q9UHI73EBI-10172052,EBI-1759386
SLC6A20Q9NP913EBI-10172052,EBI-10311198
SMARCE1Q969G33EBI-10172052,EBI-455078
SMCPP499013EBI-10172052,EBI-750494
SPATA8Q6RVD63EBI-10172052,EBI-8635958
SPG7Q9UQ903EBI-10172052,EBI-717201
SPRY1O436093EBI-10172052,EBI-3866665
SPRY2O435973EBI-10172052,EBI-742487
STK16O757163EBI-10172052,EBI-749295
TBC1D23Q9NUY83EBI-10172052,EBI-2853126
TBC1D23Q9NUY8-23EBI-10172052,EBI-10314276
TGOLN2O434933EBI-10172052,EBI-1752146
THAP10Q9P2Z03EBI-10172052,EBI-745404
TNFRSF6BO954073EBI-10172052,EBI-524171
TNP2Q4VB563EBI-10172052,EBI-10241829
TRIM41Q8WV445EBI-10172052,EBI-725997
TRIM42A1L4B63EBI-10172052,EBI-10172216
TRIM42Q8IWZ53EBI-10172052,EBI-5235829
TXNDC5Q86UY03EBI-10172052,EBI-2825190
TYMSOSQ8TAI13EBI-10172052,EBI-742060
TYRO3Q064183EBI-10172052,EBI-3951628
UTP23Q9BRU93EBI-10172052,EBI-5457544
WNT11O960143EBI-10172052,EBI-8058160
WT1-ASQ062503EBI-10172052,EBI-10223946
XCL2Q9UBD33EBI-10172052,EBI-10319095
ZBTB24O431673EBI-10172052,EBI-744471
ZBTB9Q96C003EBI-10172052,EBI-395708
ZFYVE26Q96H433EBI-10172052,EBI-10286915
ZNF124Q159733EBI-10172052,EBI-2555767
ZNF155Q12901-23EBI-10172052,EBI-10227379
ZNF20P170243EBI-10172052,EBI-717634
ZNF264Q14C613EBI-10172052,EBI-2826570
ZNF317Q96PQ6-43EBI-10172052,EBI-10292528
ZNF417Q8TAU33EBI-10172052,EBI-740727
ZNF439Q8NDP43EBI-10172052,EBI-747580
ZNF440Q8IYI83EBI-10172052,EBI-726439
ZNF473Q8WTR73EBI-10172052,EBI-751409
ZNF564Q8TBZ83EBI-10172052,EBI-10273713
ZNF572A1L4E93EBI-10172052,EBI-10172590
ZNF572Q7Z3I73EBI-10172052,EBI-10257016
ZNF578Q3MI943EBI-10172052,EBI-10241108
ZNF581Q9P0T43EBI-10172052,EBI-745520
ZNF587Q96SQ53EBI-10172052,EBI-6427977
ZNF625Q96I273EBI-10172052,EBI-4395587
ZNF697Q8N5083EBI-10172052,EBI-10265733
ZNF699Q32M783EBI-10172052,EBI-10217363
ZNF792Q3KQV33EBI-10172052,EBI-10240849
ZNF844Q08AG53EBI-10172052,EBI-10225757
ZSCAN21Q9Y5A63EBI-10172052,EBI-10281938
ZSCAN26Q166703EBI-10172052,EBI-3920053

Protein-protein interaction databases

BioGridi132127. 164 interactions.
132129. 15 interactions.
IntActiP60411. 160 interactions.
STRINGi9606.ENSP00000381009.

Structurei

3D structure databases

ProteinModelPortaliP60411.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Repeati26 – 3051
Repeati31 – 3552
Repeati36 – 4053
Repeati57 – 6154
Repeati79 – 8355
Repeati99 – 10356
Repeati104 – 10857
Repeati109 – 11358
Repeati114 – 11859
Repeati120 – 124510
Repeati130 – 134511
Repeati140 – 144512
Repeati145 – 149513
Repeati150 – 154514
Repeati162 – 166515
Repeati172 – 176516
Repeati182 – 186517
Repeati187 – 191518
Repeati192 – 196519
Repeati197 – 201520
Repeati209 – 213521
Repeati219 – 223522
Repeati224 – 228523
Repeati243 – 247524
Repeati250 – 254525

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni26 – 25422925 X 5 AA repeats of C-C-X(3)Add
BLAST

Sequence similaritiesi

Belongs to the KRTAP type 10 family.Curated

Keywords - Domaini

Repeat

Phylogenomic databases

eggNOGiNOG270891.
GeneTreeiENSGT00780000121948.
HOGENOMiHOG000234031.
HOVERGENiHBG108072.
InParanoidiP60411.
OMAiEPSCCSS.
OrthoDBiEOG780RQD.
PhylomeDBiP60411.
TreeFamiTF351356.

Family and domain databases

InterProiIPR002494. KAP.
[Graphical view]
PANTHERiPTHR23262. PTHR23262. 1 hit.
PfamiPF13885. Keratin_B2_2. 4 hits.
[Graphical view]

Sequencei

Sequence statusi: Complete.

This entry describes 1 isoform i produced by alternative splicing. AlignAdd to basket

Note: A number of isoforms are produced.

Isoform 1 (identifier: P60411-1) [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
MAASTMSIRS SAYSDSWQVD DCPESCCEPP CCATSCCAPA PCLTLVCTPV
60 70 80 90 100
SRVSSPCCQV TCEPSPCQSG CTSSCTPSCC QQSSCQPAYC TSSPCQQACC
110 120 130 140 150
VPVCCKPVCC VPVCCGASSC CQQSSYQPAC CASSSCQPAC CVPVCCKPVC
160 170 180 190 200
CAPTCSEDSY SCCQQSSCQP ACCTSSPCQQ SYCVPVCCKP VCCKPICCVP
210 220 230 240 250
VCSGASSLCC QQSGCQPACC TTSCCRPSSS VSLLCRPVCR PACCVPVSSC
260 270 280 290
CAPTSSRQPS YCRQASCVSL LCRPVCSRPA CYSFSSGQKS SC
Length:292
Mass (Da):30,037
Last modified:April 20, 2010 - v2
Checksum:iE61D891212803B98
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti102 – 1021P → PVCCKT in EAX09409 (Ref. 3) Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti182 – 1821Y → C.1 Publication
Corresponds to variant rs8127342 [ dbSNP | Ensembl ].
VAR_017739
Natural varianti257 – 2571R → C.2 Publications
Corresponds to variant rs9980129 [ dbSNP | Ensembl ].
VAR_060052

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB076356 mRNA. Translation: BAD01543.1.
AL773602 Genomic DNA. No translation available.
CH471079 Genomic DNA. Translation: EAX09409.1.
CH471079 Genomic DNA. Translation: EAX09411.1.
BC131613 mRNA. Translation: AAI31614.1.
AJ566386 mRNA. Translation: CAD97466.1.
CCDSiCCDS42961.1. [P60411-1]
RefSeqiNP_941963.2. NM_198690.2. [P60411-1]
NP_941965.2. NM_198692.2.
UniGeneiHs.474000.
Hs.58076.

Genome annotation databases

EnsembliENST00000397911; ENSP00000381009; ENSG00000221837. [P60411-1]
GeneIDi386676.
386678.
KEGGihsa:386676.
hsa:386678.
UCSCiuc002zfp.4. human. [P60411-1]

Polymorphism and mutation databases

BioMutaiKRTAP10-9.

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AB076356 mRNA. Translation: BAD01543.1.
AL773602 Genomic DNA. No translation available.
CH471079 Genomic DNA. Translation: EAX09409.1.
CH471079 Genomic DNA. Translation: EAX09411.1.
BC131613 mRNA. Translation: AAI31614.1.
AJ566386 mRNA. Translation: CAD97466.1.
CCDSiCCDS42961.1. [P60411-1]
RefSeqiNP_941963.2. NM_198690.2. [P60411-1]
NP_941965.2. NM_198692.2.
UniGeneiHs.474000.
Hs.58076.

3D structure databases

ProteinModelPortaliP60411.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi132127. 164 interactions.
132129. 15 interactions.
IntActiP60411. 160 interactions.
STRINGi9606.ENSP00000381009.

PTM databases

PhosphoSiteiP60411.

Polymorphism and mutation databases

BioMutaiKRTAP10-9.
DMDMi294862449.

Proteomic databases

PaxDbiP60411.
PeptideAtlasiP60411.
PRIDEiP60411.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000397911; ENSP00000381009; ENSG00000221837. [P60411-1]
GeneIDi386676.
386678.
KEGGihsa:386676.
hsa:386678.
UCSCiuc002zfp.4. human. [P60411-1]

Organism-specific databases

CTDi386676.
386678.
GeneCardsiGC21P046047.
H-InvDBHIX0040852.
HGNCiHGNC:22971. KRTAP10-9.
neXtProtiNX_P60411.
PharmGKBiPA134873081.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG270891.
GeneTreeiENSGT00780000121948.
HOGENOMiHOG000234031.
HOVERGENiHBG108072.
InParanoidiP60411.
OMAiEPSCCSS.
OrthoDBiEOG780RQD.
PhylomeDBiP60411.
TreeFamiTF351356.

Miscellaneous databases

NextBioi100980.
PROiP60411.

Gene expression databases

BgeeiP60411.
CleanExiHS_KRTAP10-9.
GenevestigatoriP60411.

Family and domain databases

InterProiIPR002494. KAP.
[Graphical view]
PANTHERiPTHR23262. PTHR23262. 1 hit.
PfamiPF13885. Keratin_B2_2. 4 hits.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "A cluster of 21 keratin-associated protein genes within introns of another gene on human chromosome 21q22.3."
    Shibuya K., Obayashi I., Asakawa S., Minoshima S., Kudoh J., Shimizu N.
    Genomics 83:679-693(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], TISSUE SPECIFICITY.
    Tissue: Hair root.
  2. "The DNA sequence of human chromosome 21."
    Hattori M., Fujiyama A., Taylor T.D., Watanabe H., Yada T., Park H.-S., Toyoda A., Ishii K., Totoki Y., Choi D.-K., Groner Y., Soeda E., Ohki M., Takagi T., Sakaki Y., Taudien S., Blechschmidt K., Polley A.
    , Menzel U., Delabar J., Kumpf K., Lehmann R., Patterson D., Reichwald K., Rump A., Schillhabel M., Schudy A., Zimmermann W., Rosenthal A., Kudoh J., Shibuya K., Kawasaki K., Asakawa S., Shintani A., Sasaki T., Nagamine K., Mitsuyama S., Antonarakis S.E., Minoshima S., Shimizu N., Nordsiek G., Hornischer K., Brandt P., Scharfe M., Schoen O., Desario A., Reichelt J., Kauer G., Bloecker H., Ramser J., Beck A., Klages S., Hennig S., Riesselmann L., Dagand E., Wehrmeyer S., Borzym K., Gardiner K., Nizetic D., Francis F., Lehrach H., Reinhardt R., Yaspo M.-L.
    Nature 405:311-319(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
  3. 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], VARIANTS CYS-182 AND CYS-257.
  5. "Hair keratin associated proteins: characterization of a second high sulfur KAP gene domain on human chromosome 21."
    Rogers M.A., Langbein L., Winter H., Beckmann I., Praetzel S., Schweizer J.
    J. Invest. Dermatol. 122:147-158(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 244-292, TISSUE SPECIFICITY, VARIANT CYS-257.
    Tissue: Scalp.

Entry informationi

Entry nameiKR109_HUMAN
AccessioniPrimary (citable) accession number: P60411
Secondary accession number(s): A2RRG1, A6NIR9, Q70LJ1
Entry historyi
Integrated into UniProtKB/Swiss-Prot: February 16, 2004
Last sequence update: April 20, 2010
Last modified: April 29, 2015
This is version 89 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 21
    Human chromosome 21: 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. 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.