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Protein

Transmembrane protease serine 7

Gene

TMPRSS7

Organism
Homo sapiens (Human)
Status
Reviewed-Annotation score: Annotation score: 4 out of 5-Experimental evidence at transcript leveli

Functioni

Serine protease which preferentially hydrolyzes peptides with Arg at the P1 position.By similarity

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Active sitei646 – 6461Charge relay systemBy similarity
Active sitei694 – 6941Charge relay systemBy similarity
Active sitei790 – 7901Charge relay systemBy similarity

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Hydrolase, Protease, Serine protease

Protein family/group databases

MEROPSiS01.072.

Names & Taxonomyi

Protein namesi
Recommended name:
Transmembrane protease serine 7 (EC:3.4.21.-)
Alternative name(s):
Matriptase-3
Gene namesi
Name:TMPRSS7
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 3

Organism-specific databases

HGNCiHGNC:30846. TMPRSS7.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini1 – 7676CytoplasmicSequence analysisAdd
BLAST
Transmembranei77 – 9721Helical; Signal-anchor for type II membrane proteinSequence analysisAdd
BLAST
Topological domaini98 – 843746ExtracellularSequence analysisAdd
BLAST

GO - Cellular componenti

Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Membrane

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA134928796.

Polymorphism and mutation databases

DMDMi327478556.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 843843Transmembrane protease serine 7PRO_0000027859Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Disulfide bondi247 ↔ 273By similarity
Disulfide bondi299 ↔ 322By similarity
Disulfide bondi365 ↔ 396By similarity
Disulfide bondi484 ↔ 496By similarity
Disulfide bondi491 ↔ 509By similarity
Disulfide bondi503 ↔ 518By similarity
Disulfide bondi525 ↔ 544By similarity
Disulfide bondi538 ↔ 553By similarity
Disulfide bondi559 ↔ 571By similarity
Disulfide bondi566 ↔ 585By similarity
Disulfide bondi579 ↔ 594By similarity
Disulfide bondi631 ↔ 647By similarity
Disulfide bondi730 ↔ 796By similarity
Disulfide bondi762 ↔ 775By similarity

Post-translational modificationi

N-glycosylated.By similarity

Keywords - PTMi

Disulfide bond, Glycoprotein, Zymogen

Proteomic databases

EPDiQ7RTY8.
PaxDbiQ7RTY8.
PeptideAtlasiQ7RTY8.
PRIDEiQ7RTY8.

PTM databases

iPTMnetiQ7RTY8.
PhosphoSiteiQ7RTY8.

Expressioni

Tissue specificityi

Expressed in brain, ovary, testis, salivary gland, trachea and lung.1 Publication

Gene expression databases

BgeeiQ7RTY8.
CleanExiHS_TMPRSS7.
ExpressionAtlasiQ7RTY8. baseline and differential.

Organism-specific databases

HPAiHPA040630.

Interactioni

Subunit structurei

Forms a heterodimer with SERPINA5.

Protein-protein interaction databases

STRINGi9606.ENSP00000411645.

Structurei

3D structure databases

ProteinModelPortaliQ7RTY8.
SMRiQ7RTY8. Positions 481-839.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini106 – 234129SEAPROSITE-ProRule annotationAdd
BLAST
Domaini247 – 360114CUB 1PROSITE-ProRule annotationAdd
BLAST
Domaini365 – 481117CUB 2PROSITE-ProRule annotationAdd
BLAST
Domaini483 – 51937LDL-receptor class A 1PROSITE-ProRule annotationAdd
BLAST
Domaini517 – 55438LDL-receptor class A 2PROSITE-ProRule annotationAdd
BLAST
Domaini558 – 59538LDL-receptor class A 3PROSITE-ProRule annotationAdd
BLAST
Domaini606 – 840235Peptidase S1PROSITE-ProRule annotationAdd
BLAST

Sequence similaritiesi

Belongs to the peptidase S1 family.PROSITE-ProRule annotation
Contains 2 CUB domains.PROSITE-ProRule annotation
Contains 3 LDL-receptor class A domains.PROSITE-ProRule annotation
Contains 1 peptidase S1 domain.PROSITE-ProRule annotation
Contains 1 SEA domain.PROSITE-ProRule annotation

Keywords - Domaini

Repeat, Signal-anchor, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiKOG3627. Eukaryota.
COG5640. LUCA.
GeneTreeiENSGT00840000129691.
HOGENOMiHOG000136851.
HOVERGENiHBG108591.
InParanoidiQ7RTY8.
KOiK09638.
OMAiDELFCVS.
OrthoDBiEOG75B84T.
PhylomeDBiQ7RTY8.
TreeFamiTF330647.

Family and domain databases

Gene3Di2.60.120.290. 2 hits.
3.30.70.960. 1 hit.
4.10.400.10. 2 hits.
InterProiIPR000859. CUB_dom.
IPR023415. LDLR_class-A_CS.
IPR002172. LDrepeatLR_classA_rpt.
IPR009003. Peptidase_S1_PA.
IPR001314. Peptidase_S1A.
IPR000082. SEA_dom.
IPR001254. Trypsin_dom.
IPR018114. TRYPSIN_HIS.
IPR033116. TRYPSIN_SER.
[Graphical view]
PfamiPF00431. CUB. 2 hits.
PF00057. Ldl_recept_a. 2 hits.
PF01390. SEA. 1 hit.
PF00089. Trypsin. 1 hit.
[Graphical view]
PRINTSiPR00722. CHYMOTRYPSIN.
SMARTiSM00042. CUB. 1 hit.
SM00192. LDLa. 3 hits.
SM00020. Tryp_SPc. 1 hit.
[Graphical view]
SUPFAMiSSF49854. SSF49854. 2 hits.
SSF50494. SSF50494. 1 hit.
SSF57424. SSF57424. 3 hits.
SSF82671. SSF82671. 1 hit.
PROSITEiPS01180. CUB. 2 hits.
PS01209. LDLRA_1. 1 hit.
PS50068. LDLRA_2. 2 hits.
PS50024. SEA. 1 hit.
PS50240. TRYPSIN_DOM. 1 hit.
PS00134. TRYPSIN_HIS. 1 hit.
PS00135. TRYPSIN_SER. 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: Q7RTY8-1) [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
MDKENSDVSA APADLKISNI SVQVVSAQKK LPVRRPPLPG RRLPLPGRRP
60 70 80 90 100
PQRPIGKAKP KKQSKKKVPF WNVQNKIILF TVFLFILAVI AWTLLWLYIS
110 120 130 140 150
KTESKDAFYF AGMFRITNIE FLPEYRQKES REFLSVSRTV QQVINLVYTT
160 170 180 190 200
SAFSKFYEQS VVADVSSNNK GGLLVHFWIV FVMPRAKGHI FCEDCVAAIL
210 220 230 240 250
KDSIQTSIIN RTSVGSLQGL AVDMDSVVLN AGLRSDYSST IGSDKGCSQY
260 270 280 290 300
FYAEHLSLHY PLEISAASGR LMCHFKLVAI VGYLIRLSIK SIQIEADNCV
310 320 330 340 350
TDSLTIYDSL LPIRSSILYR ICEPTRTLMS FVSTNNLMLV TFKSPHIRRL
360 370 380 390 400
SGIRAYFEVI PEQKCENTVL VKDITGFEGK ISSPYYPSYY PPKCKCTWKF
410 420 430 440 450
QTSLSTLGIA LKFYNYSITK KSMKGCEHGW WEINEHMYCG SYMDHQTIFR
460 470 480 490 500
VPSPLVHIQL QCSSRLSDKP LLAEYGSYNI SQPCPVGSFR CSSGLCVPQA
510 520 530 540 550
QRCDGVNDCF DESDELFCVS PQPACNTSSF RQHGPLICDG FRDCENGRDE
560 570 580 590 600
QNCTQSIPCN NRTFKCGNDI CFRKQNAKCD GTVDCPDGSD EEGCTCSRSS
610 620 630 640 650
SALHRIIGGT DTLEGGWPWQ VSLHFVGSAY CGASVISREW LLSAAHCFHG
660 670 680 690 700
NRLSDPTPWT AHLGMYVQGN AKFVSPVRRI VVHEYYNSQT FDYDIALLQL
710 720 730 740 750
SIAWPETLKQ LIQPICIPPT GQRVRSGEKC WVTGWGRRHE ADNKGSLVLQ
760 770 780 790 800
QAEVELIDQT LCVSTYGIIT SRMLCAGIMS GKRDACKGDS GGPLSCRRKS
810 820 830 840
DGKWILTGIV SWGHGSGRPN FPGVYTRVSN FVPWIHKYVP SLL
Note: Gene prediction based on similarity to mouse ortholog.
Length:843
Mass (Da):94,415
Last modified:April 5, 2011 - v3
Checksum:i8D97E984FD87934C
GO
Isoform 2 (identifier: Q7RTY8-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-112: Missing.
     166-166: Missing.
     231-243: Missing.

Show »
Length:717
Mass (Da):80,354
Checksum:i95151028202683C8
GO
Isoform 3 (identifier: Q7RTY8-3) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-271: Missing.

Show »
Length:572
Mass (Da):64,025
Checksum:i0458CBFB987EA285
GO

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti816 – 8161S → C in BAD18401 (PubMed:14702039).Curated
Sequence conflicti816 – 8161S → C in AAI17323 (PubMed:15489334).Curated

Alternative sequence

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Alternative sequencei1 – 271271Missing in isoform 3. 1 PublicationVSP_040771Add
BLAST
Alternative sequencei1 – 112112Missing in isoform 2. 1 PublicationVSP_040772Add
BLAST
Alternative sequencei166 – 1661Missing in isoform 2. 1 PublicationVSP_040773
Alternative sequencei231 – 24313Missing in isoform 2. 1 PublicationVSP_040774Add
BLAST

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AC015778 Genomic DNA. No translation available.
AC024887 Genomic DNA. No translation available.
AK131211 mRNA. Translation: BAD18401.1.
BC117322 mRNA. Translation: AAI17323.1.
BN000125 mRNA. Translation: CAD67577.1.
CCDSiCCDS43129.2. [Q7RTY8-2]
RefSeqiNP_001036040.2. NM_001042575.2. [Q7RTY8-2]
UniGeneiHs.435490.

Genome annotation databases

EnsembliENST00000419127; ENSP00000411645; ENSG00000176040. [Q7RTY8-2]
ENST00000452346; ENSP00000398236; ENSG00000176040. [Q7RTY8-1]
ENST00000617607; ENSP00000478830; ENSG00000176040. [Q7RTY8-2]
GeneIDi344805.
KEGGihsa:344805.
UCSCiuc010hqb.3. human. [Q7RTY8-1]

Keywords - Coding sequence diversityi

Alternative splicing

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AC015778 Genomic DNA. No translation available.
AC024887 Genomic DNA. No translation available.
AK131211 mRNA. Translation: BAD18401.1.
BC117322 mRNA. Translation: AAI17323.1.
BN000125 mRNA. Translation: CAD67577.1.
CCDSiCCDS43129.2. [Q7RTY8-2]
RefSeqiNP_001036040.2. NM_001042575.2. [Q7RTY8-2]
UniGeneiHs.435490.

3D structure databases

ProteinModelPortaliQ7RTY8.
SMRiQ7RTY8. Positions 481-839.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

STRINGi9606.ENSP00000411645.

Protein family/group databases

MEROPSiS01.072.

PTM databases

iPTMnetiQ7RTY8.
PhosphoSiteiQ7RTY8.

Polymorphism and mutation databases

DMDMi327478556.

Proteomic databases

EPDiQ7RTY8.
PaxDbiQ7RTY8.
PeptideAtlasiQ7RTY8.
PRIDEiQ7RTY8.

Protocols and materials databases

DNASUi344805.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000419127; ENSP00000411645; ENSG00000176040. [Q7RTY8-2]
ENST00000452346; ENSP00000398236; ENSG00000176040. [Q7RTY8-1]
ENST00000617607; ENSP00000478830; ENSG00000176040. [Q7RTY8-2]
GeneIDi344805.
KEGGihsa:344805.
UCSCiuc010hqb.3. human. [Q7RTY8-1]

Organism-specific databases

CTDi344805.
GeneCardsiTMPRSS7.
HGNCiHGNC:30846. TMPRSS7.
HPAiHPA040630.
neXtProtiNX_Q7RTY8.
PharmGKBiPA134928796.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG3627. Eukaryota.
COG5640. LUCA.
GeneTreeiENSGT00840000129691.
HOGENOMiHOG000136851.
HOVERGENiHBG108591.
InParanoidiQ7RTY8.
KOiK09638.
OMAiDELFCVS.
OrthoDBiEOG75B84T.
PhylomeDBiQ7RTY8.
TreeFamiTF330647.

Miscellaneous databases

ChiTaRSiTMPRSS7. human.
GenomeRNAii344805.
PROiQ7RTY8.

Gene expression databases

BgeeiQ7RTY8.
CleanExiHS_TMPRSS7.
ExpressionAtlasiQ7RTY8. baseline and differential.

Family and domain databases

Gene3Di2.60.120.290. 2 hits.
3.30.70.960. 1 hit.
4.10.400.10. 2 hits.
InterProiIPR000859. CUB_dom.
IPR023415. LDLR_class-A_CS.
IPR002172. LDrepeatLR_classA_rpt.
IPR009003. Peptidase_S1_PA.
IPR001314. Peptidase_S1A.
IPR000082. SEA_dom.
IPR001254. Trypsin_dom.
IPR018114. TRYPSIN_HIS.
IPR033116. TRYPSIN_SER.
[Graphical view]
PfamiPF00431. CUB. 2 hits.
PF00057. Ldl_recept_a. 2 hits.
PF01390. SEA. 1 hit.
PF00089. Trypsin. 1 hit.
[Graphical view]
PRINTSiPR00722. CHYMOTRYPSIN.
SMARTiSM00042. CUB. 1 hit.
SM00192. LDLa. 3 hits.
SM00020. Tryp_SPc. 1 hit.
[Graphical view]
SUPFAMiSSF49854. SSF49854. 2 hits.
SSF50494. SSF50494. 1 hit.
SSF57424. SSF57424. 3 hits.
SSF82671. SSF82671. 1 hit.
PROSITEiPS01180. CUB. 2 hits.
PS01209. LDLRA_1. 1 hit.
PS50068. LDLRA_2. 2 hits.
PS50024. SEA. 1 hit.
PS50240. TRYPSIN_DOM. 1 hit.
PS00134. TRYPSIN_HIS. 1 hit.
PS00135. TRYPSIN_SER. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "The DNA sequence, annotation and analysis of human chromosome 3."
    Muzny D.M., Scherer S.E., Kaul R., Wang J., Yu J., Sudbrak R., Buhay C.J., Chen R., Cree A., Ding Y., Dugan-Rocha S., Gill R., Gunaratne P., Harris R.A., Hawes A.C., Hernandez J., Hodgson A.V., Hume J.
    , Jackson A., Khan Z.M., Kovar-Smith C., Lewis L.R., Lozado R.J., Metzker M.L., Milosavljevic A., Miner G.R., Morgan M.B., Nazareth L.V., Scott G., Sodergren E., Song X.-Z., Steffen D., Wei S., Wheeler D.A., Wright M.W., Worley K.C., Yuan Y., Zhang Z., Adams C.Q., Ansari-Lari M.A., Ayele M., Brown M.J., Chen G., Chen Z., Clendenning J., Clerc-Blankenburg K.P., Chen R., Chen Z., Davis C., Delgado O., Dinh H.H., Dong W., Draper H., Ernst S., Fu G., Gonzalez-Garay M.L., Garcia D.K., Gillett W., Gu J., Hao B., Haugen E., Havlak P., He X., Hennig S., Hu S., Huang W., Jackson L.R., Jacob L.S., Kelly S.H., Kube M., Levy R., Li Z., Liu B., Liu J., Liu W., Lu J., Maheshwari M., Nguyen B.-V., Okwuonu G.O., Palmeiri A., Pasternak S., Perez L.M., Phelps K.A., Plopper F.J., Qiang B., Raymond C., Rodriguez R., Saenphimmachak C., Santibanez J., Shen H., Shen Y., Subramanian S., Tabor P.E., Verduzco D., Waldron L., Wang J., Wang J., Wang Q., Williams G.A., Wong G.K.-S., Yao Z., Zhang J., Zhang X., Zhao G., Zhou J., Zhou Y., Nelson D., Lehrach H., Reinhardt R., Naylor S.L., Yang H., Olson M., Weinstock G., Gibbs R.A.
    Nature 440:1194-1198(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Tissue: Teratocarcinoma.
  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 3).
  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 2).
  4. "Human and mouse proteases: a comparative genomic approach."
    Puente X.S., Sanchez L.M., Overall C.M., Lopez-Otin C.
    Nat. Rev. Genet. 4:544-558(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION.
  5. "Matriptase-3 is a novel phylogenetically preserved membrane-anchored serine protease with broad serpin reactivity."
    Szabo R., Netzel-Arnett S., Hobson J.P., Antalis T.M., Bugge T.H.
    Biochem. J. 390:231-242(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: TISSUE SPECIFICITY, HETERODIMER WITH SERPINA5.

Entry informationi

Entry nameiTMPS7_HUMAN
AccessioniPrimary (citable) accession number: Q7RTY8
Secondary accession number(s): C9J8P7, E9PAS3, Q17RH4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: March 15, 2005
Last sequence update: April 5, 2011
Last modified: July 6, 2016
This is version 120 of the entry and version 3 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 3
    Human chromosome 3: entries, gene names and cross-references to MIM
  2. Peptidase families
    Classification of peptidase families and list of entries
  3. 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.