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Protein

Zinc finger protein 16

Gene

ZNF16

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

Functioni

Acts as a transcriptional activator. Promotes cell proliferation by facilitating the cell cycle phase transition from the S to G2/M phase. Involved in both the hemin- and phorbol myristate acetate (PMA)-induced erythroid and megakaryocytic differentiation, respectively. Plays also a role as an inhibitor of cell apoptosis.3 Publications

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri209 – 23123C2H2-type 1; degeneratePROSITE-ProRule annotationAdd
BLAST
Zinc fingeri237 – 25923C2H2-type 2; degeneratePROSITE-ProRule annotationAdd
BLAST
Zinc fingeri265 – 28723C2H2-type 3PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri293 – 31523C2H2-type 4PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri321 – 34323C2H2-type 5PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri349 – 37123C2H2-type 6PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri377 – 39923C2H2-type 7PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri405 – 42723C2H2-type 8PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri433 – 45523C2H2-type 9PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri461 – 48323C2H2-type 10PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri489 – 51123C2H2-type 11PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri517 – 53923C2H2-type 12PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri545 – 56723C2H2-type 13PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri573 – 59523C2H2-type 14PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri601 – 62323C2H2-type 15PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri629 – 65123C2H2-type 16PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri657 – 67923C2H2-type 17PROSITE-ProRule annotationAdd
BLAST

GO - Molecular functioni

GO - Biological processi

  • cell cycle Source: UniProtKB-KW
  • cell division Source: UniProtKB-KW
  • cellular response to sodium dodecyl sulfate Source: UniProtKB
  • negative regulation of apoptotic process Source: UniProtKB
  • positive regulation of cell cycle phase transition Source: UniProtKB
  • positive regulation of cell division Source: UniProtKB-KW
  • positive regulation of cell proliferation Source: UniProtKB
  • positive regulation of erythrocyte differentiation Source: UniProtKB
  • positive regulation of kinase activity Source: UniProtKB
  • positive regulation of megakaryocyte differentiation Source: UniProtKB
  • regulation of transcription, DNA-templated Source: GO_Central
  • transcription, DNA-templated Source: UniProtKB-KW
Complete GO annotation...

Keywords - Molecular functioni

Activator, Mitogen

Keywords - Biological processi

Cell cycle, Cell division, Transcription, Transcription regulation

Keywords - Ligandi

DNA-binding, Metal-binding, Zinc

Names & Taxonomyi

Protein namesi
Recommended name:
Zinc finger protein 16
Alternative name(s):
Zinc finger protein KOX9
Gene namesi
Name:ZNF16
Synonyms:HZF1, KOX9
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 8

Organism-specific databases

HGNCiHGNC:12947. ZNF16.

Subcellular locationi

  • Nucleus 1 Publication

GO - Cellular componenti

  • nucleus Source: UniProtKB
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Organism-specific databases

PharmGKBiPA37530.

Polymorphism and mutation databases

BioMutaiZNF16.
DMDMi68846743.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 682682Zinc finger protein 16PRO_0000047338Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei487 – 4871N6-acetyllysineCombined sources

Keywords - PTMi

Acetylation

Proteomic databases

EPDiP17020.
MaxQBiP17020.
PaxDbiP17020.
PeptideAtlasiP17020.
PRIDEiP17020.

PTM databases

iPTMnetiP17020.
PhosphoSiteiP17020.

Expressioni

Tissue specificityi

Ubiquitous.1 Publication

Inductioni

Up-regulated by hemin during erythroid differentiation. Up-regulated by phorbol myristate acetate (PMA) during megakaryocytic differentiation. Up-regulated by the transcriptional activator MEF2A.2 Publications

Gene expression databases

BgeeiP17020.
CleanExiHS_ZNF16.
ExpressionAtlasiP17020. baseline and differential.
GenevisibleiP17020. HS.

Organism-specific databases

HPAiHPA035782.

Interactioni

Subunit structurei

Interacts with INCA1; the interaction inhibits INCA1 activity and induces the cell cycle process.1 Publication

Binary interactionsi

WithEntry#Exp.IntActNotes
INCA1Q0VD862EBI-3921553,EBI-6509505
ZNF101Q8IZC73EBI-3921553,EBI-5278328

Protein-protein interaction databases

BioGridi113395. 5 interactions.
IntActiP17020. 31 interactions.
STRINGi9606.ENSP00000276816.

Structurei

3D structure databases

ProteinModelPortaliP17020.
SMRiP17020. Positions 151-682.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni62 – 210149Necessary for transcription activationAdd
BLAST
Regioni268 – 393126Required for nuclear localizationAdd
BLAST
Regioni341 – 37333Required for nuclear localizationAdd
BLAST
Regioni473 – 50331Required for nuclear localizationAdd
BLAST

Sequence similaritiesi

Contains 17 C2H2-type zinc fingers.PROSITE-ProRule annotation

Zinc finger

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri209 – 23123C2H2-type 1; degeneratePROSITE-ProRule annotationAdd
BLAST
Zinc fingeri237 – 25923C2H2-type 2; degeneratePROSITE-ProRule annotationAdd
BLAST
Zinc fingeri265 – 28723C2H2-type 3PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri293 – 31523C2H2-type 4PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri321 – 34323C2H2-type 5PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri349 – 37123C2H2-type 6PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri377 – 39923C2H2-type 7PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri405 – 42723C2H2-type 8PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri433 – 45523C2H2-type 9PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri461 – 48323C2H2-type 10PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri489 – 51123C2H2-type 11PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri517 – 53923C2H2-type 12PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri545 – 56723C2H2-type 13PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri573 – 59523C2H2-type 14PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri601 – 62323C2H2-type 15PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri629 – 65123C2H2-type 16PROSITE-ProRule annotationAdd
BLAST
Zinc fingeri657 – 67923C2H2-type 17PROSITE-ProRule annotationAdd
BLAST

Keywords - Domaini

Repeat, Zinc-finger

Phylogenomic databases

eggNOGiKOG1721. Eukaryota.
COG5048. LUCA.
GeneTreeiENSGT00840000129692.
HOGENOMiHOG000234617.
HOVERGENiHBG018163.
InParanoidiP17020.
OMAiPDLIQHQ.
OrthoDBiEOG7KSX7Q.
PhylomeDBiP17020.
TreeFamiTF337005.

Family and domain databases

Gene3Di3.30.160.60. 17 hits.
InterProiIPR007087. Znf_C2H2.
IPR015880. Znf_C2H2-like.
IPR013087. Znf_C2H2/integrase_DNA-bd.
[Graphical view]
PfamiPF00096. zf-C2H2. 11 hits.
PF13912. zf-C2H2_6. 1 hit.
[Graphical view]
SMARTiSM00355. ZnF_C2H2. 17 hits.
[Graphical view]
PROSITEiPS00028. ZINC_FINGER_C2H2_1. 15 hits.
PS50157. ZINC_FINGER_C2H2_2. 17 hits.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P17020-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MPSLRTRREE AEMELSVPGP SPWTPAAQAR VRDAPAVTHP GSAACGTPCC
60 70 80 90 100
SDTELEAICP HYQQPDCDTR TEDKEFLHKE DIHEDLESQA EISENYAGDV
110 120 130 140 150
SQVPELGDLC DDVSERDWGV PEGRRLPQSL SQEGDFTPAA MGLLRGPLGE
160 170 180 190 200
KDLDCNGFDS RFSLSPNLMA CQEIPTEERP HPYDMGGQSF QHSVDLTGHE
210 220 230 240 250
GVPTAESPLI CNECGKTFQG NPDLIQRQIV HTGEASFMCD DCGKTFSQNS
260 270 280 290 300
VLKNRHRSHM SEKAYQCSEC GKAFRGHSDF SRHQSHHSSE RPYMCNECGK
310 320 330 340 350
AFSQNSSLKK HQKSHMSEKP YECNECGKAF RRSSNLIQHQ RIHSGEKPYV
360 370 380 390 400
CSECGKAFRR SSNLIKHHRT HTGEKPFECG ECGKAFSQSA HLRKHQRVHT
410 420 430 440 450
GEKPYECNDC GKPFSRVSNL IKHHRVHTGE KPYKCSDCGK AFSQSSSLIQ
460 470 480 490 500
HRRIHTGEKP HVCNVCGKAF SYSSVLRKHQ IIHTGEKPYR CSVCGKAFSH
510 520 530 540 550
SSALIQHQGV HTGDKPYACH ECGKTFGRSS NLILHQRVHT GEKPYECTEC
560 570 580 590 600
GKTFSQSSTL IQHQRIHNGL KPHECNQCGK AFNRSSNLIH HQKVHTGEKP
610 620 630 640 650
YTCVECGKGF SQSSHLIQHQ IIHTGERPYK CSECGKAFSQ RSVLIQHQRI
660 670 680
HTGVKPYDCA ACGKAFSQRS KLIKHQLIHT RE
Length:682
Mass (Da):76,472
Last modified:July 5, 2005 - v3
Checksum:i3D4FA38552001430
GO

Sequence cautioni

The sequence AAF75235.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated
The sequence AAZ20773.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti105 – 1051E → K.
Corresponds to variant rs3735784 [ dbSNP | Ensembl ].
VAR_024193
Natural varianti227 – 2271R → H.
Corresponds to variant rs3735786 [ dbSNP | Ensembl ].
VAR_024194

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF244088 mRNA. Translation: AAF75235.1. Different initiation.
DQ117529 mRNA. Translation: AAZ20773.1. Different initiation.
AK127625 mRNA. Translation: BAG54536.1.
CH471162 Genomic DNA. Translation: EAW82027.1.
CH471162 Genomic DNA. Translation: EAW82028.1.
BC010996 mRNA. Translation: AAH10996.2.
X52340 mRNA. Translation: CAA36566.1.
CCDSiCCDS6437.1.
PIRiI37977.
RefSeqiNP_001025147.2. NM_001029976.2.
NP_008889.2. NM_006958.2.
XP_005272398.1. XM_005272341.2.
XP_011515600.1. XM_011517298.1.
UniGeneiHs.493225.

Genome annotation databases

EnsembliENST00000276816; ENSP00000276816; ENSG00000170631.
ENST00000394909; ENSP00000378369; ENSG00000170631.
ENST00000611477; ENSP00000484504; ENSG00000170631.
GeneIDi7564.
KEGGihsa:7564.
UCSCiuc003zet.3. human.

Keywords - Coding sequence diversityi

Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AF244088 mRNA. Translation: AAF75235.1. Different initiation.
DQ117529 mRNA. Translation: AAZ20773.1. Different initiation.
AK127625 mRNA. Translation: BAG54536.1.
CH471162 Genomic DNA. Translation: EAW82027.1.
CH471162 Genomic DNA. Translation: EAW82028.1.
BC010996 mRNA. Translation: AAH10996.2.
X52340 mRNA. Translation: CAA36566.1.
CCDSiCCDS6437.1.
PIRiI37977.
RefSeqiNP_001025147.2. NM_001029976.2.
NP_008889.2. NM_006958.2.
XP_005272398.1. XM_005272341.2.
XP_011515600.1. XM_011517298.1.
UniGeneiHs.493225.

3D structure databases

ProteinModelPortaliP17020.
SMRiP17020. Positions 151-682.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi113395. 5 interactions.
IntActiP17020. 31 interactions.
STRINGi9606.ENSP00000276816.

PTM databases

iPTMnetiP17020.
PhosphoSiteiP17020.

Polymorphism and mutation databases

BioMutaiZNF16.
DMDMi68846743.

Proteomic databases

EPDiP17020.
MaxQBiP17020.
PaxDbiP17020.
PeptideAtlasiP17020.
PRIDEiP17020.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000276816; ENSP00000276816; ENSG00000170631.
ENST00000394909; ENSP00000378369; ENSG00000170631.
ENST00000611477; ENSP00000484504; ENSG00000170631.
GeneIDi7564.
KEGGihsa:7564.
UCSCiuc003zet.3. human.

Organism-specific databases

CTDi7564.
GeneCardsiZNF16.
HGNCiHGNC:12947. ZNF16.
HPAiHPA035782.
MIMi601262. gene.
neXtProtiNX_P17020.
PharmGKBiPA37530.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG1721. Eukaryota.
COG5048. LUCA.
GeneTreeiENSGT00840000129692.
HOGENOMiHOG000234617.
HOVERGENiHBG018163.
InParanoidiP17020.
OMAiPDLIQHQ.
OrthoDBiEOG7KSX7Q.
PhylomeDBiP17020.
TreeFamiTF337005.

Miscellaneous databases

ChiTaRSiZNF16. human.
GeneWikiiZNF16.
GenomeRNAii7564.
PROiP17020.
SOURCEiSearch...

Gene expression databases

BgeeiP17020.
CleanExiHS_ZNF16.
ExpressionAtlasiP17020. baseline and differential.
GenevisibleiP17020. HS.

Family and domain databases

Gene3Di3.30.160.60. 17 hits.
InterProiIPR007087. Znf_C2H2.
IPR015880. Znf_C2H2-like.
IPR013087. Znf_C2H2/integrase_DNA-bd.
[Graphical view]
PfamiPF00096. zf-C2H2. 11 hits.
PF13912. zf-C2H2_6. 1 hit.
[Graphical view]
SMARTiSM00355. ZnF_C2H2. 17 hits.
[Graphical view]
PROSITEiPS00028. ZINC_FINGER_C2H2_1. 15 hits.
PS50157. ZINC_FINGER_C2H2_2. 17 hits.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Identification and characterization of a novel zinc finger protein (HZF1) gene and its function in erythroid and megakaryocytic differentiation of K562 cells."
    Peng H., Du Z.W., Zhang J.W.
    Leukemia 20:1109-1116(2006) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, INDUCTION, SUBCELLULAR LOCATION, TISSUE SPECIFICITY.
    Tissue: Bone marrow.
  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].
  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].
    Tissue: Ovary.
  5. "Multiple genes encoding zinc finger domains are expressed in human T cells."
    Thiesen H.-J.
    New Biol. 2:363-374(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 461-516.
    Tissue: Lymphoid tissue.
  6. "Lysine acetylation targets protein complexes and co-regulates major cellular functions."
    Choudhary C., Kumar C., Gnad F., Nielsen M.L., Rehman M., Walther T.C., Olsen J.V., Mann M.
    Science 325:834-840(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: ACETYLATION [LARGE SCALE ANALYSIS] AT LYS-487, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  7. "Identification of the trans-activation domain and the nuclear location signals of human zinc finger protein HZF1 (ZNF16)."
    Deng M.J., Li X.B., Peng H., Zhang J.W.
    Mol. Biotechnol. 44:83-89(2010) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION.
  8. "Identification of HZF1 as a novel target gene of the MEF2 transcription factor."
    Liu X., Jin E.Z., Zhi J.X., Li X.Q.
    Mol. Med. Report. 4:465-469(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: INDUCTION.
  9. "Zinc finger protein HZF1 promotes K562 cell proliferation by interacting with and inhibiting INCA1."
    Li X.B., Chen J., Deng M.J., Wang F., Du Z.W., Zhang J.W.
    Mol. Med. Report. 4:1131-1137(2011) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, INTERACTION WITH INCA1.

Entry informationi

Entry nameiZNF16_HUMAN
AccessioniPrimary (citable) accession number: P17020
Secondary accession number(s): B3KXM4
, D3DWP2, Q45SH7, Q96FG0, Q9NRA4
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 1, 1990
Last sequence update: July 5, 2005
Last modified: July 6, 2016
This is version 164 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 8
    Human chromosome 8: 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.