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Protein

1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase beta-4

Gene

PLCB4

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

Functioni

The production of the second messenger molecules diacylglycerol (DAG) and inositol 1,4,5-trisphosphate (IP3) is mediated by activated phosphatidylinositol-specific phospholipase C enzymes. This form has a role in retina signal transduction.

Catalytic activityi

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

Cofactori

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Active sitei328PROSITE-ProRule annotation1
Active sitei375PROSITE-ProRule annotation1

GO - Molecular functioni

GO - Biological processi

Complete GO annotation...

Keywords - Molecular functioni

Hydrolase, Transducer

Keywords - Biological processi

Lipid degradation, Lipid metabolism

Keywords - Ligandi

Calcium

Enzyme and pathway databases

BioCyciZFISH:HS02244-MONOMER.
BRENDAi3.1.4.11. 2681.
ReactomeiR-HSA-112043. PLC beta mediated events.
R-HSA-1855204. Synthesis of IP3 and IP4 in the cytosol.
R-HSA-416476. G alpha (q) signalling events.

Names & Taxonomyi

Protein namesi
Recommended name:
1-phosphatidylinositol 4,5-bisphosphate phosphodiesterase beta-4 (EC:3.1.4.11)
Alternative name(s):
Phosphoinositide phospholipase C-beta-4
Phospholipase C-beta-4
Short name:
PLC-beta-4
Gene namesi
Name:PLCB4
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
Proteomesi
  • UP000005640 Componenti: Chromosome 20

Organism-specific databases

HGNCiHGNC:9059. PLCB4.

Subcellular locationi

GO - Cellular componenti

Complete GO annotation...

Pathology & Biotechi

Involvement in diseasei

Auriculocondylar syndrome 2 (ARCND2)1 Publication
The disease is caused by mutations affecting the gene represented in this entry.
Disease descriptionA craniofacial malformation syndrome characterized by variable mandibular anomalies, including mild to severe micrognathia, temporomandibular joint ankylosis, cleft palate, and a characteristic ear malformation that consists of separation of the lobule from the external ear, giving the appearance of a question mark (question-mark ear). Other frequently described features include prominent cheeks, cupped and posteriorly rotated ears, preauricular tags, and microstomia.
See also OMIM:614669
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_068559329N → T in ARCND2. 1 Publication1
Natural variantiVAR_068560621R → C in ARCND2. 1 PublicationCorresponds to variant rs397514482dbSNPEnsembl.1
Natural variantiVAR_068561621R → H in ARCND2. 1 PublicationCorresponds to variant rs397514481dbSNPEnsembl.1
Natural variantiVAR_068562623Y → C in ARCND2. 1 PublicationCorresponds to variant rs397514480dbSNPEnsembl.1
Natural variantiVAR_068563650N → H in ARCND2. 1 PublicationCorresponds to variant rs397514483dbSNPEnsembl.1

Keywords - Diseasei

Disease mutation

Organism-specific databases

DisGeNETi5332.
MalaCardsiPLCB4.
MIMi614669. phenotype.
OpenTargetsiENSG00000101333.
Orphaneti137888. Auriculocondylar syndrome.
PharmGKBiPA33387.

Polymorphism and mutation databases

BioMutaiPLCB4.

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemoved1 Publication
ChainiPRO_00000884952 – 11751-phosphatidylinositol 4,5-bisphosphate phosphodiesterase beta-4Add BLAST1174

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei2N-acetylalanine1 Publication1
Modified residuei886PhosphothreonineCombined sources1

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiQ15147.
PaxDbiQ15147.
PeptideAtlasiQ15147.
PRIDEiQ15147.

PTM databases

iPTMnetiQ15147.
PhosphoSitePlusiQ15147.
SwissPalmiQ15147.

Expressioni

Tissue specificityi

Preferentially expressed in the retina.

Gene expression databases

BgeeiENSG00000101333.
ExpressionAtlasiQ15147. baseline and differential.
GenevisibleiQ15147. HS.

Organism-specific databases

HPAiHPA007951.

Interactioni

Binary interactionsi

WithEntry#Exp.IntActNotes
RELQ048643EBI-998637,EBI-307352

Protein-protein interaction databases

BioGridi111348. 1 interactor.
DIPiDIP-36735N.
IntActiQ15147. 3 interactors.
STRINGi9606.ENSP00000334105.

Structurei

3D structure databases

ProteinModelPortaliQ15147.
SMRiQ15147.
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Domaini313 – 463PI-PLC X-boxPROSITE-ProRule annotationAdd BLAST151
Domaini565 – 681PI-PLC Y-boxPROSITE-ProRule annotationAdd BLAST117
Domaini688 – 786C2PROSITE-ProRule annotationAdd BLAST99

Sequence similaritiesi

Contains 1 C2 domain.PROSITE-ProRule annotation
Contains 1 PI-PLC X-box domain.PROSITE-ProRule annotation
Contains 1 PI-PLC Y-box domain.PROSITE-ProRule annotation

Phylogenomic databases

eggNOGiKOG0169. Eukaryota.
ENOG410XPSW. LUCA.
GeneTreeiENSGT00760000118936.
HOGENOMiHOG000232046.
HOVERGENiHBG053609.
InParanoidiQ15147.
KOiK05858.
OMAiNISFTYM.
OrthoDBiEOG091G00XL.
PhylomeDBiQ15147.
TreeFamiTF352235.

Family and domain databases

Gene3Di1.10.238.10. 1 hit.
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.
IPR011993. PH_dom-like.
IPR001192. PI-PLC_fam.
IPR016280. PLC-beta.
IPR009535. PLC-beta_CS.
IPR017946. PLC-like_Pdiesterase_TIM-brl.
IPR015359. PLC_EF-hand-like.
IPR000909. PLipase_C_PInositol-sp_X_dom.
IPR001711. PLipase_C_Pinositol-sp_Y.
[Graphical view]
PANTHERiPTHR10336. PTHR10336. 2 hits.
PfamiPF00168. C2. 1 hit.
PF06631. DUF1154. 1 hit.
PF09279. EF-hand_like. 1 hit.
PF00388. PI-PLC-X. 1 hit.
PF00387. PI-PLC-Y. 1 hit.
[Graphical view]
PIRSFiPIRSF000956. PLC-beta. 1 hit.
PRINTSiPR00390. PHPHLIPASEC.
SMARTiSM00239. C2. 1 hit.
SM00148. PLCXc. 1 hit.
SM00149. PLCYc. 1 hit.
[Graphical view]
SUPFAMiSSF47473. SSF47473. 1 hit.
SSF49562. SSF49562. 1 hit.
SSF50729. SSF50729. 1 hit.
SSF51695. SSF51695. 2 hits.
PROSITEiPS50004. C2. 1 hit.
PS50007. PIPLC_X_DOMAIN. 1 hit.
PS50008. PIPLC_Y_DOMAIN. 1 hit.
[Graphical view]

Sequences (4)i

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

This entry describes 4 isoformsi produced by alternative splicing. AlignAdd to basket

Note: Additional isoforms seem to exist.
Isoform 2 (identifier: Q15147-1) [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
MAKPYEFNWQ KEVPSFLQEG AVFDRYEEES FVFEPNCLFK VDEFGFFLTW
60 70 80 90 100
RSEGKEGQVL ECSLINSIRS GAIPKDPKIL AALEAVGKSE NDLEGRIVCV
110 120 130 140 150
CSGTDLVNIS FTYMVAENPE VTKQWVEGLR SIIHNFRANN VSPMTCLKKH
160 170 180 190 200
WMKLAFMTNT NGKIPVRSIT RTFASGKTEK VIFQALKELG LPSGKNDEIE
210 220 230 240 250
PTAFSYEKFY ELTQKICPRT DIEDLFKKIN GDKTDYLTVD QLVSFLNEHQ
260 270 280 290 300
RDPRLNEILF PFYDAKRAMQ IIEMYEPDED LKKKGLISSD GFCRYLMSDE
310 320 330 340 350
NAPVFLDRLE LYQEMDHPLA HYFISSSHNT YLTGRQFGGK SSVEMYRQVL
360 370 380 390 400
LAGCRCVELD CWDGKGEDQE PIITHGKAMC TDILFKDVIQ AIKETAFVTS
410 420 430 440 450
EYPVILSFEN HCSKYQQYKM SKYCEDLFGD LLLKQALESH PLEPGRALPS
460 470 480 490 500
PNDLKRKILI KNKRLKPEVE KKQLEALRSM MEAGESASPA NILEDDNEEE
510 520 530 540 550
IESADQEEEA HPEFKFGNEL SADDLGHKEA VANSVKKGLV TVEDEQAWMA
560 570 580 590 600
SYKYVGATTN IHPYLSTMIN YAQPVKFQGF HVAEERNIHY NMSSFNESVG
610 620 630 640 650
LGYLKTHAIE FVNYNKRQMS RIYPKGGRVD SSNYMPQIFW NAGCQMVSLN
660 670 680 690 700
YQTPDLAMQL NQGKFEYNGS CGYLLKPDFM RRPDRTFDPF SETPVDGVIA
710 720 730 740 750
ATCSVQVISG QFLSDKKIGT YVEVDMYGLP TDTIRKEFRT RMVMNNGLNP
760 770 780 790 800
VYNEESFVFR KVILPDLAVL RIAVYDDNNK LIGQRILPLD GLQAGYRHIS
810 820 830 840 850
LRNEGNKPLS LPTIFCNIVL KTYVPDGFGD IVDALSDPKK FLSITEKRAD
860 870 880 890 900
QMRAMGIETS DIADVPSDTS KNDKKGKANT AKANVTPQSS SELRPTTTAA
910 920 930 940 950
LASGVEAKKG IELIPQVRIE DLKQMKAYLK HLKKQQKELN SLKKKHAKEH
960 970 980 990 1000
STMQKLHCTQ VDKIVAQYDK EKSTHEKILE KAMKKKGGSN CLEMKKETEI
1010 1020 1030 1040 1050
KIQTLTSDHK SKVKEIVAQH TKEWSEMINT HSAEEQEIRD LHLSQQCELL
1060 1070 1080 1090 1100
KKLLINAHEQ QTQQLKLSHD RESKEMRAHQ AKISMENSKA ISQDKSIKNK
1110 1120 1130 1140 1150
AERERRVREL NSSNTKKFLE ERKRLAMKQS KEMDQLKKVQ LEHLEFLEKQ
1160 1170
NEQAKEMQQM VKLEAEMDRR PATVV
Length:1,175
Mass (Da):134,464
Last modified:December 5, 2001 - v3
Checksum:iAB2C8EB99EF57357
GO
Isoform 1 (identifier: Q15147-2) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1-153: Missing.
     154-167: LAFMTNTNGKIPVR → MNNNWNVCFFLFCP

Show »
Length:1,022
Mass (Da):117,162
Checksum:i4A6A14188161A46C
GO
Isoform 3 (identifier: Q15147-4) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     1154-1175: AKEMQQMVKLEAEMDRRPATVV → LLKSCHAVSQTQGEGDAADGEIGSRDGPQTSNSSMKLQNAN

Note: No experimental confirmation available.
Show »
Length:1,194
Mass (Da):136,106
Checksum:iE6A0912E517D182C
GO
Isoform 4 (identifier: Q15147-5) [UniParc]FASTAAdd to basket

The sequence of this isoform differs from the canonical sequence as follows:
     535-535: V → VKKASDDLEHENN

Note: No experimental confirmation available.
Show »
Length:1,187
Mass (Da):135,845
Checksum:i8EC5C7445E1052AA
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti447A → P in AAB02027 (PubMed:8530101).Curated1
Sequence conflicti757F → L in AAB02027 (PubMed:8530101).Curated1
Sequence conflicti787L → P in AAB02027 (PubMed:8530101).Curated1
Sequence conflicti840K → T in AAB02027 (PubMed:8530101).Curated1
Sequence conflicti902A → P in AAB02027 (PubMed:8530101).Curated1

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural variantiVAR_05669421A → T.1 PublicationCorresponds to variant rs6077510dbSNPEnsembl.1
Natural variantiVAR_068559329N → T in ARCND2. 1 Publication1
Natural variantiVAR_068560621R → C in ARCND2. 1 PublicationCorresponds to variant rs397514482dbSNPEnsembl.1
Natural variantiVAR_068561621R → H in ARCND2. 1 PublicationCorresponds to variant rs397514481dbSNPEnsembl.1
Natural variantiVAR_068562623Y → C in ARCND2. 1 PublicationCorresponds to variant rs397514480dbSNPEnsembl.1
Natural variantiVAR_068563650N → H in ARCND2. 1 PublicationCorresponds to variant rs397514483dbSNPEnsembl.1
Natural variantiVAR_056695710G → S.Corresponds to variant rs6118603dbSNPEnsembl.1

Alternative sequence

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Alternative sequenceiVSP_0047211 – 153Missing in isoform 1. 1 PublicationAdd BLAST153
Alternative sequenceiVSP_004722154 – 167LAFMT…KIPVR → MNNNWNVCFFLFCP in isoform 1. 1 PublicationAdd BLAST14
Alternative sequenceiVSP_055182535V → VKKASDDLEHENN in isoform 4. Curated1
Alternative sequenceiVSP_0378181154 – 1175AKEMQ…PATVV → LLKSCHAVSQTQGEGDAADG EIGSRDGPQTSNSSMKLQNA N in isoform 3. CuratedAdd BLAST22

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L41349 mRNA. Translation: AAB02027.1.
AL121898 Genomic DNA. No translation available.
AL121909 Genomic DNA. No translation available.
AL031652, AL023805 Genomic DNA. Translation: CAI42213.1.
AL023805, AL031652 Genomic DNA. Translation: CAI43087.1.
AL031652, AL023805 Genomic DNA. Translation: CAI42218.2.
AL023805, AL031652 Genomic DNA. Translation: CAI43092.2.
BC117458 mRNA. Translation: AAI17459.1.
BC143868 mRNA. Translation: AAI43869.1.
CCDSiCCDS13104.1. [Q15147-4]
CCDS13105.1. [Q15147-1]
CCDS54447.1. [Q15147-5]
RefSeqiNP_000924.3. NM_000933.3. [Q15147-4]
NP_001166117.1. NM_001172646.1. [Q15147-5]
NP_877949.2. NM_182797.2. [Q15147-1]
XP_016883369.1. XM_017027880.1. [Q15147-4]
XP_016883370.1. XM_017027881.1. [Q15147-1]
UniGeneiHs.472101.

Genome annotation databases

EnsembliENST00000278655; ENSP00000278655; ENSG00000101333. [Q15147-1]
ENST00000378473; ENSP00000367734; ENSG00000101333. [Q15147-5]
ENST00000378493; ENSP00000367754; ENSG00000101333. [Q15147-1]
ENST00000378501; ENSP00000367762; ENSG00000101333. [Q15147-4]
ENST00000414679; ENSP00000390616; ENSG00000101333. [Q15147-5]
GeneIDi5332.
KEGGihsa:5332.
UCSCiuc010gbx.4. human. [Q15147-1]

Keywords - Coding sequence diversityi

Alternative splicing, Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
L41349 mRNA. Translation: AAB02027.1.
AL121898 Genomic DNA. No translation available.
AL121909 Genomic DNA. No translation available.
AL031652, AL023805 Genomic DNA. Translation: CAI42213.1.
AL023805, AL031652 Genomic DNA. Translation: CAI43087.1.
AL031652, AL023805 Genomic DNA. Translation: CAI42218.2.
AL023805, AL031652 Genomic DNA. Translation: CAI43092.2.
BC117458 mRNA. Translation: AAI17459.1.
BC143868 mRNA. Translation: AAI43869.1.
CCDSiCCDS13104.1. [Q15147-4]
CCDS13105.1. [Q15147-1]
CCDS54447.1. [Q15147-5]
RefSeqiNP_000924.3. NM_000933.3. [Q15147-4]
NP_001166117.1. NM_001172646.1. [Q15147-5]
NP_877949.2. NM_182797.2. [Q15147-1]
XP_016883369.1. XM_017027880.1. [Q15147-4]
XP_016883370.1. XM_017027881.1. [Q15147-1]
UniGeneiHs.472101.

3D structure databases

ProteinModelPortaliQ15147.
SMRiQ15147.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi111348. 1 interactor.
DIPiDIP-36735N.
IntActiQ15147. 3 interactors.
STRINGi9606.ENSP00000334105.

PTM databases

iPTMnetiQ15147.
PhosphoSitePlusiQ15147.
SwissPalmiQ15147.

Polymorphism and mutation databases

BioMutaiPLCB4.

Proteomic databases

MaxQBiQ15147.
PaxDbiQ15147.
PeptideAtlasiQ15147.
PRIDEiQ15147.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000278655; ENSP00000278655; ENSG00000101333. [Q15147-1]
ENST00000378473; ENSP00000367734; ENSG00000101333. [Q15147-5]
ENST00000378493; ENSP00000367754; ENSG00000101333. [Q15147-1]
ENST00000378501; ENSP00000367762; ENSG00000101333. [Q15147-4]
ENST00000414679; ENSP00000390616; ENSG00000101333. [Q15147-5]
GeneIDi5332.
KEGGihsa:5332.
UCSCiuc010gbx.4. human. [Q15147-1]

Organism-specific databases

CTDi5332.
DisGeNETi5332.
GeneCardsiPLCB4.
HGNCiHGNC:9059. PLCB4.
HPAiHPA007951.
MalaCardsiPLCB4.
MIMi600810. gene.
614669. phenotype.
neXtProtiNX_Q15147.
OpenTargetsiENSG00000101333.
Orphaneti137888. Auriculocondylar syndrome.
PharmGKBiPA33387.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiKOG0169. Eukaryota.
ENOG410XPSW. LUCA.
GeneTreeiENSGT00760000118936.
HOGENOMiHOG000232046.
HOVERGENiHBG053609.
InParanoidiQ15147.
KOiK05858.
OMAiNISFTYM.
OrthoDBiEOG091G00XL.
PhylomeDBiQ15147.
TreeFamiTF352235.

Enzyme and pathway databases

BioCyciZFISH:HS02244-MONOMER.
BRENDAi3.1.4.11. 2681.
ReactomeiR-HSA-112043. PLC beta mediated events.
R-HSA-1855204. Synthesis of IP3 and IP4 in the cytosol.
R-HSA-416476. G alpha (q) signalling events.

Miscellaneous databases

ChiTaRSiPLCB4. human.
GeneWikiiPLCB4.
GenomeRNAii5332.
PROiQ15147.
SOURCEiSearch...

Gene expression databases

BgeeiENSG00000101333.
ExpressionAtlasiQ15147. baseline and differential.
GenevisibleiQ15147. HS.

Family and domain databases

Gene3Di1.10.238.10. 1 hit.
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.
IPR011993. PH_dom-like.
IPR001192. PI-PLC_fam.
IPR016280. PLC-beta.
IPR009535. PLC-beta_CS.
IPR017946. PLC-like_Pdiesterase_TIM-brl.
IPR015359. PLC_EF-hand-like.
IPR000909. PLipase_C_PInositol-sp_X_dom.
IPR001711. PLipase_C_Pinositol-sp_Y.
[Graphical view]
PANTHERiPTHR10336. PTHR10336. 2 hits.
PfamiPF00168. C2. 1 hit.
PF06631. DUF1154. 1 hit.
PF09279. EF-hand_like. 1 hit.
PF00388. PI-PLC-X. 1 hit.
PF00387. PI-PLC-Y. 1 hit.
[Graphical view]
PIRSFiPIRSF000956. PLC-beta. 1 hit.
PRINTSiPR00390. PHPHLIPASEC.
SMARTiSM00239. C2. 1 hit.
SM00148. PLCXc. 1 hit.
SM00149. PLCYc. 1 hit.
[Graphical view]
SUPFAMiSSF47473. SSF47473. 1 hit.
SSF49562. SSF49562. 1 hit.
SSF50729. SSF50729. 1 hit.
SSF51695. SSF51695. 2 hits.
PROSITEiPS50004. C2. 1 hit.
PS50007. PIPLC_X_DOMAIN. 1 hit.
PS50008. PIPLC_Y_DOMAIN. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiPLCB4_HUMAN
AccessioniPrimary (citable) accession number: Q15147
Secondary accession number(s): B7ZLK6
, E2QRH8, Q17R56, Q5JYS8, Q5JYS9, Q5JYT0, Q5JYT3, Q5JYT4, Q9BQW5, Q9BQW6, Q9BQW8, Q9UJQ2
Entry historyi
Integrated into UniProtKB/Swiss-Prot: January 11, 2001
Last sequence update: December 5, 2001
Last modified: November 30, 2016
This is version 174 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, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 20
    Human chromosome 20: 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.