Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase delta-3

Gene

Plcd3

Organism
Mus musculus (Mouse)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Hydrolyzes the phosphatidylinositol 4,5-bisphosphate (PIP2) to generate 2 second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3). DAG mediates the activation of protein kinase C (PKC), while IP3 releases Ca2+ from intracellular stores. Essential for trophoblast and placental development. May participate in cytokinesis by hydrolyzing PIP2 at the cleavage furrow.1 Publication

Catalytic activityi

1-phosphatidyl-1D-myo-inositol 4,5-bisphosphate + H2O = 1D-myo-inositol 1,4,5-trisphosphate + diacylglycerol.

Cofactori

Ca2+By similarityNote: Binds 3 Ca(2+) ions per subunit. Two of the Ca2+ ions are bound to the C2 domain.By similarity

Enzyme regulationi

Strongly activated by phosphatidic acid. Inhibited by phosphatidylethanolamine (PtdEtn), phosphatidylcholine (PtdCho), sphingomyelin and phosphatidylserine (PtdSer) (By similarity).By similarity

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Active sitei348 – 3481PROSITE-ProRule annotation
Metal bindingi349 – 3491Calcium 1; catalyticBy similarity
Metal bindingi378 – 3781Calcium 1; catalyticBy similarity
Metal bindingi380 – 3801Calcium 1; catalyticBy similarity
Active sitei393 – 3931PROSITE-ProRule annotation
Metal bindingi427 – 4271Calcium 1; catalyticBy similarity
Binding sitei476 – 4761SubstrateBy similarity
Binding sitei478 – 4781SubstrateBy similarity
Binding sitei553 – 5531SubstrateBy similarity
Binding sitei580 – 5801SubstrateBy similarity
Metal bindingi679 – 6791Calcium 2; via carbonyl oxygenBy similarity
Metal bindingi681 – 6811Calcium 2By similarity
Metal bindingi705 – 7051Calcium 2By similarity
Metal bindingi734 – 7341Calcium 3By similarity
Metal bindingi735 – 7351Calcium 3; via carbonyl oxygenBy similarity
Metal bindingi736 – 7361Calcium 3By similarity

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Calcium bindingi191 – 202121Sequence AnalysisAdd
BLAST
Calcium bindingi227 – 238122Sequence AnalysisAdd
BLAST

GO - Molecular functioni

  1. metal ion binding Source: UniProtKB-KW
  2. phosphatidylinositol phospholipase C activity Source: UniProtKB-EC
  3. signal transducer activity Source: UniProtKB-KW

GO - Biological processi

  1. angiogenesis Source: MGI
  2. intracellular signal transduction Source: InterPro
  3. labyrinthine layer blood vessel development Source: MGI
  4. lipid catabolic process Source: UniProtKB-KW
  5. regulation of cell proliferation Source: MGI
Complete GO annotation...

Keywords - Molecular functioni

Hydrolase, Transducer

Keywords - Biological processi

Lipid degradation, Lipid metabolism

Keywords - Ligandi

Calcium, Metal-binding

Enzyme and pathway databases

ReactomeiREACT_321652. Synthesis of IP3 and IP4 in the cytosol.

Names & Taxonomyi

Protein namesi
Recommended name:
1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase delta-3 (EC:3.1.4.11)
Alternative name(s):
Phosphoinositide phospholipase C-delta-3
Phospholipase C-delta-3
Short name:
PLC-delta-3
Gene namesi
Name:Plcd3
Synonyms:Kiaa1964
OrganismiMus musculus (Mouse)
Taxonomic identifieri10090 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresGliresRodentiaSciurognathiMuroideaMuridaeMurinaeMusMus
ProteomesiUP000000589 Componenti: Chromosome 11

Organism-specific databases

MGIiMGI:107451. Plcd3.

Subcellular locationi

Membrane By similarity; Peripheral membrane protein By similarity. Cytoplasm By similarity. Cleavage furrow
Note: Localizes at the cleavage furrow during cytokinesis.

GO - Cellular componenti

  1. cleavage furrow Source: UniProtKB-SubCell
  2. cytosol Source: Ensembl
  3. membrane Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

Cytoplasm, Membrane

Pathology & Biotechi

Disruption phenotypei

Mice lacking Plcd1 and Plcd3 die between 11.5 and 13.5 dpc. They exhibit severe disruption of the normal labyrinth architecture in the placenta and decreased placental vascularization, as well as abnormal proliferation and apoptosis of trophoblasts in the labyrinth area. Furthermore, Plcd1 and Plcd3 double knockout embryos supplied with a normal placenta by the tetraploid aggregation method survive beyond 14.5 dpc, indicating that the embryonic lethality is caused by a defect in trophoblasts.1 Publication

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 7857851-phosphatidylinositol 4,5-bisphosphate phosphodiesterase delta-3PRO_0000306822Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei101 – 1011PhosphoserineBy similarity
Modified residuei492 – 4921Phosphoserine1 Publication

Keywords - PTMi

Phosphoprotein

Proteomic databases

MaxQBiQ8K2J0.
PaxDbiQ8K2J0.
PRIDEiQ8K2J0.

PTM databases

PhosphoSiteiQ8K2J0.

Expressioni

Gene expression databases

BgeeiQ8K2J0.
CleanExiMM_PLCD3.
GenevestigatoriQ8K2J0.

Structurei

3D structure databases

SMRiQ8K2J0. Positions 51-784.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini65 – 168104PHAdd
BLAST
Domaini178 – 21336EF-hand 1Add
BLAST
Domaini214 – 24936EF-hand 2Add
BLAST
Domaini246 – 28136EF-hand 3Add
BLAST
Domaini333 – 478146PI-PLC X-boxPROSITE-ProRule annotationAdd
BLAST
Domaini524 – 640117PI-PLC Y-boxPROSITE-ProRule annotationAdd
BLAST
Domaini643 – 748106C2PROSITE-ProRule annotationAdd
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni69 – 9729Substrate bindingBy similarityAdd
BLAST

Domaini

The C2 domain is a Ca2+-dependent membrane-targeting module.By similarity
The PH domain mediates interaction with the surface membrane by binding to PIP2.By similarity

Sequence similaritiesi

Contains 1 C2 domain.PROSITE-ProRule annotation
Contains 3 EF-hand domains.Curated
Contains 1 PH domain.Curated
Contains 1 PI-PLC X-box domain.PROSITE-ProRule annotation
Contains 1 PI-PLC Y-box domain.PROSITE-ProRule annotation

Keywords - Domaini

Repeat

Phylogenomic databases

eggNOGiNOG149692.
GeneTreeiENSGT00760000118936.
HOGENOMiHOG000006871.
HOVERGENiHBG053610.
InParanoidiQ8K2J0.
KOiK05857.
OMAiHWGQTLQ.
OrthoDBiEOG7V49XT.
PhylomeDBiQ8K2J0.
TreeFamiTF313216.

Family and domain databases

Gene3Di1.10.238.10. 2 hits.
2.30.29.30. 1 hit.
2.60.40.150. 1 hit.
3.20.20.190. 2 hits.
InterProiIPR000008. C2_dom.
IPR011992. EF-hand-dom_pair.
IPR001849. PH_domain.
IPR011993. PH_like_dom.
IPR001192. PI-PLC_fam.
IPR028406. PLC-delta3.
IPR017946. PLC-like_Pdiesterase_TIM-brl.
IPR015359. PLipase_C_EF-hand-like.
IPR000909. PLipase_C_PInositol-sp_X_dom.
IPR001711. PLipase_C_Pinositol-sp_Y.
[Graphical view]
PANTHERiPTHR10336. PTHR10336. 1 hit.
PTHR10336:SF33. PTHR10336:SF33. 1 hit.
PfamiPF00168. C2. 1 hit.
PF09279. EF-hand_like. 1 hit.
PF00388. PI-PLC-X. 1 hit.
PF00387. PI-PLC-Y. 1 hit.
[Graphical view]
PRINTSiPR00390. PHPHLIPASEC.
SMARTiSM00239. C2. 1 hit.
SM00233. PH. 1 hit.
SM00148. PLCXc. 1 hit.
SM00149. PLCYc. 1 hit.
[Graphical view]
SUPFAMiSSF49562. SSF49562. 1 hit.
SSF51695. SSF51695. 1 hit.
PROSITEiPS50004. C2. 1 hit.
PS50007. PIPLC_X_DOMAIN. 1 hit.
PS50008. PIPLC_Y_DOMAIN. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

Q8K2J0-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MLCGGWKRSR RSPEESRVSA QVAAPLAFPP SPASSDSSTK RPGLRALKKM
60 70 80 90 100
GLTEDEDVQA MLRGSRLLKI RSRTWHKERL YRLQEDGLSV WFQRRIPRAA
110 120 130 140 150
SKHIFFVQHI EAVREGHQSE GLRRFGGAFA PACCLTIAFK GRRKNLDLAA
160 170 180 190 200
PTAEEAQRWV RGLAKLRARL DAMSQRERLD HWIHSYLHRA DSDQDSKMSF
210 220 230 240 250
KEIKSLLRMV NVDMNDMYAY RLFKECDHSN NERLEGAEIE AFLRRLLKRP
260 270 280 290 300
ELEEIFRRYS GEDRVLSASE LLEFLEDQGE DGATLACAQQ LIQTYELNET
310 320 330 340 350
AKQHELMTLD GFMMYLLSPE GAALNVAHTC VFQDMGQPLA HYFISSSHNT
360 370 380 390 400
YLTDSQIGGT SSTEAYIRAF AQGCRCVELD CWEGPGGEPV IYHGHTLTSK
410 420 430 440 450
ILFRDVIQAV RDHAFTSSPY PVILSLENHC GLEQQAVMAR HLRSILGDML
460 470 480 490 500
VTQALDSQNP EELPSPEQLK GRILVKGKKL PAARSEDGRI LSDREEEEEE
510 520 530 540 550
EEEAEEALEA AEQRSRAKQI SPELSALAVY CCATRLRTLD PSPGPPQSCT
560 570 580 590 600
VGSLSERKAR KFTREAGTSF VRHNTQQLTR VYPLGLRMNS ANYNPQEMWN
610 620 630 640 650
SGCQLVALNF QTPGYEMDLN TGRFLINGQC GYVLKPAYLR QLNTTFDPEC
660 670 680 690 700
PGPPRTTLAI QVLTAQQLPK LNAEKPSSIV DPLVRVEIHG VPEDCAQKET
710 720 730 740 750
DYVLNNGFNP CWEQTLQFRL RAPELVLVRF VVEDYDTTSP NDFVGQSTLP
760 770 780
LSSLKQGYRH IHLLSKDGAS LAPATLFVHI RIQNS
Length:785
Mass (Da):88,607
Last modified:October 2, 2007 - v2
Checksum:i8B3DE84FB7A52238
GO

Sequence cautioni

The sequence BAC32829.1 differs from that shown. Reason: Erroneous initiation. Curated
The sequence BAD32589.1 differs from that shown.Intron retention.Curated
The sequence CAM22088.1 differs from that shown. Reason: Erroneous gene model prediction. Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti199 – 1991S → N in BAE26150 (PubMed:16141072).Curated
Sequence conflicti301 – 3022AK → GE in BAD32589 (PubMed:15368895).Curated
Sequence conflicti378 – 3781E → K in BAE26150 (PubMed:16141072).Curated
Sequence conflicti540 – 5401D → E in AAH31392 (PubMed:15489334).Curated
Sequence conflicti659 – 6591A → T in BAE26150 (PubMed:16141072).Curated
Sequence conflicti660 – 6601I → V in BAE26150 (PubMed:16141072).Curated

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AK173311 Transcribed RNA. Translation: BAD32589.1. Sequence problems.
AK046669 mRNA. Translation: BAC32829.1. Different initiation.
AK144950 mRNA. Translation: BAE26150.1.
AL731805 Genomic DNA. Translation: CAM22088.1. Sequence problems.
AL731805 Genomic DNA. Translation: CAM22089.1.
BC031392 mRNA. Translation: AAH31392.1.
CCDSiCCDS25512.1.
RefSeqiNP_690026.2. NM_152813.3.
UniGeneiMm.264743.

Genome annotation databases

EnsembliENSMUST00000103077; ENSMUSP00000099366; ENSMUSG00000020937.
GeneIDi72469.
KEGGimmu:72469.
UCSCiuc007ltf.2. mouse.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
AK173311 Transcribed RNA. Translation: BAD32589.1. Sequence problems.
AK046669 mRNA. Translation: BAC32829.1. Different initiation.
AK144950 mRNA. Translation: BAE26150.1.
AL731805 Genomic DNA. Translation: CAM22088.1. Sequence problems.
AL731805 Genomic DNA. Translation: CAM22089.1.
BC031392 mRNA. Translation: AAH31392.1.
CCDSiCCDS25512.1.
RefSeqiNP_690026.2. NM_152813.3.
UniGeneiMm.264743.

3D structure databases

SMRiQ8K2J0. Positions 51-784.
ModBaseiSearch...
MobiDBiSearch...

PTM databases

PhosphoSiteiQ8K2J0.

Proteomic databases

MaxQBiQ8K2J0.
PaxDbiQ8K2J0.
PRIDEiQ8K2J0.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENSMUST00000103077; ENSMUSP00000099366; ENSMUSG00000020937.
GeneIDi72469.
KEGGimmu:72469.
UCSCiuc007ltf.2. mouse.

Organism-specific databases

CTDi113026.
MGIiMGI:107451. Plcd3.
RougeiSearch...

Phylogenomic databases

eggNOGiNOG149692.
GeneTreeiENSGT00760000118936.
HOGENOMiHOG000006871.
HOVERGENiHBG053610.
InParanoidiQ8K2J0.
KOiK05857.
OMAiHWGQTLQ.
OrthoDBiEOG7V49XT.
PhylomeDBiQ8K2J0.
TreeFamiTF313216.

Enzyme and pathway databases

ReactomeiREACT_321652. Synthesis of IP3 and IP4 in the cytosol.

Miscellaneous databases

NextBioi336294.
PROiQ8K2J0.
SOURCEiSearch...

Gene expression databases

BgeeiQ8K2J0.
CleanExiMM_PLCD3.
GenevestigatoriQ8K2J0.

Family and domain databases

Gene3Di1.10.238.10. 2 hits.
2.30.29.30. 1 hit.
2.60.40.150. 1 hit.
3.20.20.190. 2 hits.
InterProiIPR000008. C2_dom.
IPR011992. EF-hand-dom_pair.
IPR001849. PH_domain.
IPR011993. PH_like_dom.
IPR001192. PI-PLC_fam.
IPR028406. PLC-delta3.
IPR017946. PLC-like_Pdiesterase_TIM-brl.
IPR015359. PLipase_C_EF-hand-like.
IPR000909. PLipase_C_PInositol-sp_X_dom.
IPR001711. PLipase_C_Pinositol-sp_Y.
[Graphical view]
PANTHERiPTHR10336. PTHR10336. 1 hit.
PTHR10336:SF33. PTHR10336:SF33. 1 hit.
PfamiPF00168. C2. 1 hit.
PF09279. EF-hand_like. 1 hit.
PF00388. PI-PLC-X. 1 hit.
PF00387. PI-PLC-Y. 1 hit.
[Graphical view]
PRINTSiPR00390. PHPHLIPASEC.
SMARTiSM00239. C2. 1 hit.
SM00233. PH. 1 hit.
SM00148. PLCXc. 1 hit.
SM00149. PLCYc. 1 hit.
[Graphical view]
SUPFAMiSSF49562. SSF49562. 1 hit.
SSF51695. SSF51695. 1 hit.
PROSITEiPS50004. C2. 1 hit.
PS50007. PIPLC_X_DOMAIN. 1 hit.
PS50008. PIPLC_Y_DOMAIN. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Prediction of the coding sequences of mouse homologues of KIAA gene: IV. The complete nucleotide sequences of 500 mouse KIAA-homologous cDNAs identified by screening of terminal sequences of cDNA clones randomly sampled from size-fractionated libraries."
    Okazaki N., Kikuno R., Ohara R., Inamoto S., Koseki H., Hiraoka S., Saga Y., Seino S., Nishimura M., Kaisho T., Hoshino K., Kitamura H., Nagase T., Ohara O., Koga H.
    DNA Res. 11:205-218(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Tissue: Embryonic intestine.
  2. "The transcriptional landscape of the mammalian genome."
    Carninci P., Kasukawa T., Katayama S., Gough J., Frith M.C., Maeda N., Oyama R., Ravasi T., Lenhard B., Wells C., Kodzius R., Shimokawa K., Bajic V.B., Brenner S.E., Batalov S., Forrest A.R., Zavolan M., Davis M.J.
    , Wilming L.G., Aidinis V., Allen J.E., Ambesi-Impiombato A., Apweiler R., Aturaliya R.N., Bailey T.L., Bansal M., Baxter L., Beisel K.W., Bersano T., Bono H., Chalk A.M., Chiu K.P., Choudhary V., Christoffels A., Clutterbuck D.R., Crowe M.L., Dalla E., Dalrymple B.P., de Bono B., Della Gatta G., di Bernardo D., Down T., Engstrom P., Fagiolini M., Faulkner G., Fletcher C.F., Fukushima T., Furuno M., Futaki S., Gariboldi M., Georgii-Hemming P., Gingeras T.R., Gojobori T., Green R.E., Gustincich S., Harbers M., Hayashi Y., Hensch T.K., Hirokawa N., Hill D., Huminiecki L., Iacono M., Ikeo K., Iwama A., Ishikawa T., Jakt M., Kanapin A., Katoh M., Kawasawa Y., Kelso J., Kitamura H., Kitano H., Kollias G., Krishnan S.P., Kruger A., Kummerfeld S.K., Kurochkin I.V., Lareau L.F., Lazarevic D., Lipovich L., Liu J., Liuni S., McWilliam S., Madan Babu M., Madera M., Marchionni L., Matsuda H., Matsuzawa S., Miki H., Mignone F., Miyake S., Morris K., Mottagui-Tabar S., Mulder N., Nakano N., Nakauchi H., Ng P., Nilsson R., Nishiguchi S., Nishikawa S., Nori F., Ohara O., Okazaki Y., Orlando V., Pang K.C., Pavan W.J., Pavesi G., Pesole G., Petrovsky N., Piazza S., Reed J., Reid J.F., Ring B.Z., Ringwald M., Rost B., Ruan Y., Salzberg S.L., Sandelin A., Schneider C., Schoenbach C., Sekiguchi K., Semple C.A., Seno S., Sessa L., Sheng Y., Shibata Y., Shimada H., Shimada K., Silva D., Sinclair B., Sperling S., Stupka E., Sugiura K., Sultana R., Takenaka Y., Taki K., Tammoja K., Tan S.L., Tang S., Taylor M.S., Tegner J., Teichmann S.A., Ueda H.R., van Nimwegen E., Verardo R., Wei C.L., Yagi K., Yamanishi H., Zabarovsky E., Zhu S., Zimmer A., Hide W., Bult C., Grimmond S.M., Teasdale R.D., Liu E.T., Brusic V., Quackenbush J., Wahlestedt C., Mattick J.S., Hume D.A., Kai C., Sasaki D., Tomaru Y., Fukuda S., Kanamori-Katayama M., Suzuki M., Aoki J., Arakawa T., Iida J., Imamura K., Itoh M., Kato T., Kawaji H., Kawagashira N., Kawashima T., Kojima M., Kondo S., Konno H., Nakano K., Ninomiya N., Nishio T., Okada M., Plessy C., Shibata K., Shiraki T., Suzuki S., Tagami M., Waki K., Watahiki A., Okamura-Oho Y., Suzuki H., Kawai J., Hayashizaki Y.
    Science 309:1559-1563(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Strain: C57BL/6J.
    Tissue: Adipose tissue and Mammary gland.
  3. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
    Strain: C57BL/6J.
  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(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
    Strain: FVB/N.
    Tissue: Mammary tumor.
  5. "Phospholipase C-delta1 and -delta3 are essential in the trophoblast for placental development."
    Nakamura Y., Hamada Y., Fujiwara T., Enomoto H., Hiroe T., Tanaka S., Nose M., Nakahara M., Yoshida N., Takenawa T., Fukami K.
    Mol. Cell. Biol. 25:10979-10988(2004) [PubMed] [Europe PMC] [Abstract]
    Cited for: FUNCTION, DISRUPTION PHENOTYPE.
  6. "The phagosomal proteome in interferon-gamma-activated macrophages."
    Trost M., English L., Lemieux S., Courcelles M., Desjardins M., Thibault P.
    Immunity 30:143-154(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: PHOSPHORYLATION [LARGE SCALE ANALYSIS] AT SER-492, IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].

Entry informationi

Entry nameiPLCD3_MOUSE
AccessioniPrimary (citable) accession number: Q8K2J0
Secondary accession number(s): A2AHR0
, A2AHR1, Q3UME8, Q69Z55, Q8BL19
Entry historyi
Integrated into UniProtKB/Swiss-Prot: October 2, 2007
Last sequence update: October 2, 2007
Last modified: April 1, 2015
This is version 113 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programChordata Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

Complete proteome, Reference proteome

Documents

  1. MGD cross-references
    Mouse Genome Database (MGD) cross-references in UniProtKB/Swiss-Prot
  2. 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.