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Protein

DNA polymerase alpha catalytic subunit A

Gene

POL1

Organism
Saccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
Status
Reviewed-Annotation score: Annotation score: 5 out of 5-Experimental evidence at protein leveli

Functioni

Catalytic component of DNA polymerase alpha, which in complex with DNA primase (DNA polymerase alpha:primase) constitutes a replicative polymerase. POL1 has a role in promoting telomere replication during interaction with CDC13.1 Publication

Catalytic activityi

Deoxynucleoside triphosphate + DNA(n) = diphosphate + DNA(n+1).

Cofactori

[4Fe-4S] cluster1 PublicationNote: Binds 1 [4Fe-4S] cluster.1 Publication

Sites

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Metal bindingi1287ZincBy similarity1
Metal bindingi1290ZincBy similarity1
Metal bindingi1314ZincBy similarity1
Metal bindingi1317ZincBy similarity1
Metal bindingi1348Iron-sulfur (4Fe-4S)By similarity1
Metal bindingi1353Iron-sulfur (4Fe-4S)By similarity1
Metal bindingi1367Iron-sulfur (4Fe-4S)By similarity1
Metal bindingi1372Iron-sulfur (4Fe-4S)By similarity1

Regions

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri1287 – 1317CysA-typeAdd BLAST31

GO - Molecular functioni

GO - Biological processi

  • DNA replication Source: SGD
  • DNA replication initiation Source: SGD
  • DNA synthesis involved in DNA repair Source: SGD
  • double-strand break repair Source: SGD
  • double-strand break repair via nonhomologous end joining Source: GO_Central
  • lagging strand elongation Source: SGD
  • leading strand elongation Source: GO_Central
  • premeiotic DNA replication Source: SGD
  • RNA-dependent DNA biosynthetic process Source: SGD
Complete GO annotation...

Keywords - Molecular functioni

DNA-directed DNA polymerase, Nucleotidyltransferase, Transferase

Keywords - Biological processi

DNA replication

Keywords - Ligandi

4Fe-4S, DNA-binding, Iron, Iron-sulfur, Metal-binding, Zinc

Enzyme and pathway databases

BioCyciYEAST:G3O-33130-MONOMER.
BRENDAi2.7.7.7. 984.
ReactomeiR-SCE-113501. Inhibition of replication initiation of damaged DNA by RB1/E2F1.
R-SCE-113510. E2F mediated regulation of DNA replication.
R-SCE-174411. Polymerase switching on the C-strand of the telomere.
R-SCE-174430. Telomere C-strand synthesis initiation.
R-SCE-68952. DNA replication initiation.
R-SCE-68962. Activation of the pre-replicative complex.
R-SCE-69091. Polymerase switching.
R-SCE-69166. Removal of the Flap Intermediate.
R-SCE-69183. Processive synthesis on the lagging strand.
R-SCE-69205. G1/S-Specific Transcription.

Names & Taxonomyi

Protein namesi
Recommended name:
DNA polymerase alpha catalytic subunit A (EC:2.7.7.7)
Alternative name(s):
DNA polymerase I subunit A
DNA polymerase alpha:primase complex p180 subunit
Short name:
DNA polymerase-primase complex p180 subunit
Short name:
Pol alpha-primase complex p180 subunit
Gene namesi
Name:POL1
Synonyms:CDC17
Ordered Locus Names:YNL102W
ORF Names:N2181
OrganismiSaccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
Taxonomic identifieri559292 [NCBI]
Taxonomic lineageiEukaryotaFungiDikaryaAscomycotaSaccharomycotinaSaccharomycetesSaccharomycetalesSaccharomycetaceaeSaccharomyces
Proteomesi
  • UP000002311 Componenti: Chromosome XIV

Organism-specific databases

EuPathDBiFungiDB:YNL102W.
SGDiS000005046. POL1.

Subcellular locationi

GO - Cellular componenti

  • alpha DNA polymerase:primase complex Source: SGD
  • replication fork Source: SGD
Complete GO annotation...

Keywords - Cellular componenti

Nucleus

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi236D → N: Increase in length of X' and Y' telomeres. No effect on telomere position effect. Reduced interaction with CDC13. 1 Publication1
Mutagenesisi238E → K: Increase in length of X' and Y' telomeres. Reduced interaction with CDC13. 1 Publication1
Mutagenesisi241P → T: Increase in length of X' and Y' telomeres. Reduced interaction with CDC13. 1 Publication1

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemovedCombined sources
ChainiPRO_00000464402 – 1468DNA polymerase alpha catalytic subunit AAdd BLAST1467

Amino acid modifications

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Modified residuei2N-acetylserineCombined sources1
Modified residuei31PhosphoserineCombined sources1
Modified residuei82PhosphoserineCombined sources1
Modified residuei83PhosphoserineCombined sources1
Modified residuei84PhosphoserineCombined sources1
Modified residuei169PhosphoserineCombined sources1
Modified residuei170PhosphoserineCombined sources1
Modified residuei172PhosphothreonineCombined sources1
Modified residuei240PhosphoserineCombined sources1
Modified residuei274PhosphoserineCombined sources1
Modified residuei309PhosphothreonineCombined sources1
Modified residuei313PhosphothreonineCombined sources1

Keywords - PTMi

Acetylation, Phosphoprotein

Proteomic databases

MaxQBiP13382.
PRIDEiP13382.

PTM databases

iPTMnetiP13382.

Interactioni

Subunit structurei

DNA polymerase alpha:primase is a four subunit enzyme complex, which is assembled throughout the cell cycle, and consists of the two DNA polymerase subunits A and B, and the DNA primase large and small subunits. Subunit B binds to subunit A (By similarity). POL1 interacts with CDC13, POB3, SPT16 and MCM10.By similarity4 Publications

Binary interactionsi

WithEntry#Exp.IntActNotes
CDC13P327974EBI-6128,EBI-4187
CTF4Q014545EBI-6128,EBI-5209
POL12P381215EBI-6128,EBI-6111

Protein-protein interaction databases

BioGridi35721. 203 interactors.
DIPiDIP-2526N.
IntActiP13382. 14 interactors.
MINTiMINT-421899.

Structurei

Secondary structure

11468
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Helixi141 – 148Combined sources8
Helixi217 – 239Combined sources23
Beta strandi351 – 362Combined sources12
Beta strandi365 – 373Combined sources9
Beta strandi379 – 386Combined sources8
Beta strandi390 – 397Combined sources8
Helixi403 – 418Combined sources16
Beta strandi425 – 431Combined sources7
Beta strandi441 – 453Combined sources13
Beta strandi469 – 476Combined sources8
Helixi481 – 488Combined sources8
Beta strandi496 – 499Combined sources4
Beta strandi503 – 506Combined sources4
Beta strandi511 – 520Combined sources10
Helixi522 – 524Combined sources3
Beta strandi525 – 527Combined sources3
Beta strandi536 – 548Combined sources13
Turni549 – 552Combined sources4
Beta strandi553 – 567Combined sources15
Beta strandi569 – 571Combined sources3
Beta strandi580 – 586Combined sources7
Beta strandi589 – 593Combined sources5
Helixi598 – 605Combined sources8
Beta strandi606 – 612Combined sources7
Helixi616 – 630Combined sources15
Beta strandi633 – 639Combined sources7
Turni640 – 643Combined sources4
Helixi644 – 654Combined sources11
Helixi660 – 663Combined sources4
Beta strandi664 – 666Combined sources3
Turni673 – 676Combined sources4
Helixi682 – 691Combined sources10
Beta strandi694 – 698Combined sources5
Helixi702 – 706Combined sources5
Helixi716 – 724Combined sources9
Helixi739 – 742Combined sources4
Helixi744 – 767Combined sources24
Helixi770 – 781Combined sources12
Helixi785 – 790Combined sources6
Helixi794 – 807Combined sources14
Beta strandi854 – 856Combined sources3
Beta strandi860 – 864Combined sources5
Helixi868 – 875Combined sources8
Turni880 – 882Combined sources3
Helixi905 – 926Combined sources22
Helixi930 – 947Combined sources18
Helixi948 – 950Combined sources3
Helixi951 – 955Combined sources5
Helixi964 – 987Combined sources24
Beta strandi991 – 995Combined sources5
Beta strandi997 – 1003Combined sources7
Helixi1009 – 1026Combined sources18
Beta strandi1033 – 1045Combined sources13
Beta strandi1048 – 1054Combined sources7
Beta strandi1064 – 1071Combined sources8
Helixi1072 – 1074Combined sources3
Helixi1080 – 1093Combined sources14
Beta strandi1094 – 1097Combined sources4
Helixi1101 – 1118Combined sources18
Helixi1124 – 1127Combined sources4
Beta strandi1129 – 1132Combined sources4
Helixi1137 – 1139Combined sources3
Helixi1143 – 1145Combined sources3
Helixi1147 – 1158Combined sources12
Beta strandi1167 – 1173Combined sources7
Turni1189 – 1192Combined sources4
Beta strandi1193 – 1195Combined sources3
Helixi1196 – 1200Combined sources5
Helixi1202 – 1204Combined sources3
Helixi1210 – 1215Combined sources6
Turni1216 – 1218Combined sources3
Helixi1219 – 1225Combined sources7
Turni1226 – 1228Combined sources3
Helixi1234 – 1239Combined sources6
Turni1274 – 1279Combined sources6
Beta strandi1283 – 1286Combined sources4
Turni1288 – 1290Combined sources3
Beta strandi1293 – 1296Combined sources4
Beta strandi1298 – 1300Combined sources3
Beta strandi1303 – 1308Combined sources6
Beta strandi1311 – 1314Combined sources4
Turni1315 – 1317Combined sources3
Helixi1323 – 1343Combined sources21
Beta strandi1346 – 1349Combined sources4
Turni1351 – 1353Combined sources3
Beta strandi1356 – 1358Combined sources3
Beta strandi1375 – 1380Combined sources6
Helixi1382 – 1395Combined sources14
Helixi1398 – 1402Combined sources5
Helixi1424 – 1433Combined sources10
Helixi1435 – 1449Combined sources15

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3FLOX-ray2.50B/D/F/H1263-1468[»]
3OIQX-ray2.40B215-250[»]
4B08X-ray2.67A349-1258[»]
4C93X-ray2.69D/E137-149[»]
4FVMX-ray2.30A349-1258[»]
4FXDX-ray3.00A/B349-1258[»]
4FYDX-ray3.10A/B349-1258[»]
ProteinModelPortaliP13382.
SMRiP13382.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP13382.

Family & Domainsi

Region

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Regioni1246 – 1381DNA-binding regionSequence analysisAdd BLAST136

Motif

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Motifi1348 – 1372CysB motifAdd BLAST25

Domaini

The CysB motif binds 1 4Fe-4S cluster and is required for the formation of polymerase complexes.By similarity

Sequence similaritiesi

Belongs to the DNA polymerase type-B family.Curated
Contains 1 CysA-type zinc finger.Curated

Zinc finger

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Zinc fingeri1287 – 1317CysA-typeAdd BLAST31

Keywords - Domaini

Zinc-finger

Phylogenomic databases

GeneTreeiENSGT00550000074891.
HOGENOMiHOG000163524.
InParanoidiP13382.
KOiK02320.
OMAiTDYTEVN.
OrthoDBiEOG092C038B.

Family and domain databases

Gene3Di3.30.420.10. 1 hit.
3.90.1600.10. 2 hits.
InterProiIPR006172. DNA-dir_DNA_pol_B.
IPR017964. DNA-dir_DNA_pol_B_CS.
IPR006133. DNA-dir_DNA_pol_B_exonuc.
IPR006134. DNA-dir_DNA_pol_B_multi_dom.
IPR024647. DNA_pol_a_cat_su_N.
IPR023211. DNA_pol_palm_dom.
IPR029702. POLA/Pol1.
IPR012337. RNaseH-like_dom.
IPR015088. Znf_DNA-dir_DNA_pol_B_alpha.
[Graphical view]
PANTHERiPTHR10322:SF21. PTHR10322:SF21. 4 hits.
PfamiPF12254. DNA_pol_alpha_N. 1 hit.
PF00136. DNA_pol_B. 1 hit.
PF03104. DNA_pol_B_exo1. 1 hit.
PF08996. zf-DNA_Pol. 1 hit.
[Graphical view]
PRINTSiPR00106. DNAPOLB.
SMARTiSM00486. POLBc. 1 hit.
[Graphical view]
SUPFAMiSSF53098. SSF53098. 2 hits.
PROSITEiPS00116. DNA_POLYMERASE_B. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

P13382-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MSSKSEKLEK LRKLQAARNG TSIDDYEGDE SDGDRIYDEI DEKEYRARKR
60 70 80 90 100
QELLHDDFVV DDDGVGYVDR GVEEDWREVD NSSSDEDTGN LASKDSKRKK
110 120 130 140 150
NIKREKDHQI TDMLRTQHSK STLLAHAKKS QKKSIPIDNF DDILGEFESG
160 170 180 190 200
EVEKPNILLP SKLRENLNSS PTSEFKSSIK RVNGNDESSH DAGISKKVKI
210 220 230 240 250
DPDSSTDKYL EIESSPLKLQ SRKLRYANDV QDLLDDVENS PVVATKRQNV
260 270 280 290 300
LQDTLLANPP SAQSLADEED DEDSDEDIIL KRRTMRSVTT TRRVNIDSRS
310 320 330 340 350
NPSTSPFVTA PGTPIGIKGL TPSKSLQSNT DVATLAVNVK KEDVVDPETD
360 370 380 390 400
TFQMFWLDYC EVNNTLILFG KVKLKDDNCV SAMVQINGLC RELFFLPREG
410 420 430 440 450
KTPTDIHEEI IPLLMDKYGL DNIRAKPQKM KYSFELPDIP SESDYLKVLL
460 470 480 490 500
PYQTPKSSRD TIPSDLSSDT FYHVFGGNSN IFESFVIQNR IMGPCWLDIK
510 520 530 540 550
GADFNSIRNA SHCAVEVSVD KPQNITPTTT KTMPNLRCLS LSIQTLMNPK
560 570 580 590 600
ENKQEIVSIT LSAYRNISLD SPIPENIKPD DLCTLVRPPQ STSFPLGLAA
610 620 630 640 650
LAKQKLPGRV RLFNNEKAML SCFCAMLKVE DPDVIIGHRL QNVYLDVLAH
660 670 680 690 700
RMHDLNIPTF SSIGRRLRRT WPEKFGRGNS NMNHFFISDI CSGRLICDIA
710 720 730 740 750
NEMGQSLTPK CQSWDLSEMY QVTCEKEHKP LDIDYQNPQY QNDVNSMTMA
760 770 780 790 800
LQENITNCMI SAEVSYRIQL LTLTKQLTNL AGNAWAQTLG GTRAGRNEYI
810 820 830 840 850
LLHEFSRNGF IVPDKEGNRS RAQKQRQNEE NADAPVNSKK AKYQGGLVFE
860 870 880 890 900
PEKGLHKNYV LVMDFNSLYP SIIQEFNICF TTVDRNKEDI DELPSVPPSE
910 920 930 940 950
VDQGVLPRLL ANLVDRRREV KKVMKTETDP HKRVQCDIRQ QALKLTANSM
960 970 980 990 1000
YGCLGYVNSR FYAKPLAMLV TNKGREILMN TRQLAESMNL LVVYGDTDSV
1010 1020 1030 1040 1050
MIDTGCDNYA DAIKIGLGFK RLVNERYRLL EIDIDNVFKK LLLHAKKKYA
1060 1070 1080 1090 1100
ALTVNLDKNG NGTTVLEVKG LDMKRREFCP LSRDVSIHVL NTILSDKDPE
1110 1120 1130 1140 1150
EALQEVYDYL EDIRIKVETN NIRIDKYKIN MKLSKDPKAY PGGKNMPAVQ
1160 1170 1180 1190 1200
VALRMRKAGR VVKAGSVITF VITKQDEIDN AADTPALSVA ERAHALNEVM
1210 1220 1230 1240 1250
IKSNNLIPDP QYYLEKQIFA PVERLLERID SFNVVRLSEA LGLDSKKYFR
1260 1270 1280 1290 1300
REGGNNNGED INNLQPLETT ITDVERFKDT VTLELSCPSC DKRFPFGGIV
1310 1320 1330 1340 1350
SSNYYRVSYN GLQCKHCEQL FTPLQLTSQI EHSIRAHISL YYAGWLQCDD
1360 1370 1380 1390 1400
STCGIVTRQV SVFGKRCLND GCTGVMRYKY SDKQLYNQLL YFDSLFDCEK
1410 1420 1430 1440 1450
NKKQELKPIY LPDDLDYPKE QLTESSIKAL TEQNRELMET GRSVVQKYLN
1460
DCGRRYVDMT SIFDFMLN
Length:1,468
Mass (Da):166,809
Last modified:October 1, 1996 - v2
Checksum:i50C9032DBE95B5AE
GO

Experimental Info

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Sequence conflicti759 – 760MI → IV in AAA34888 (PubMed:3287376).Curated2

Natural variant

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Natural varianti493G → R in temperature sensitive mutant. 1 Publication1

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J03268 Genomic DNA. Translation: AAA34888.1.
Z50161 Genomic DNA. Translation: CAA90524.1.
Z71378 Genomic DNA. Translation: CAA95978.1.
Z12126 Genomic DNA. Translation: CAA78111.1.
BK006947 Genomic DNA. Translation: DAA10443.1.
PIRiS58250.
RefSeqiNP_014297.3. NM_001182940.3.

Genome annotation databases

EnsemblFungiiYNL102W; YNL102W; YNL102W.
GeneIDi855621.
KEGGisce:YNL102W.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J03268 Genomic DNA. Translation: AAA34888.1.
Z50161 Genomic DNA. Translation: CAA90524.1.
Z71378 Genomic DNA. Translation: CAA95978.1.
Z12126 Genomic DNA. Translation: CAA78111.1.
BK006947 Genomic DNA. Translation: DAA10443.1.
PIRiS58250.
RefSeqiNP_014297.3. NM_001182940.3.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
3FLOX-ray2.50B/D/F/H1263-1468[»]
3OIQX-ray2.40B215-250[»]
4B08X-ray2.67A349-1258[»]
4C93X-ray2.69D/E137-149[»]
4FVMX-ray2.30A349-1258[»]
4FXDX-ray3.00A/B349-1258[»]
4FYDX-ray3.10A/B349-1258[»]
ProteinModelPortaliP13382.
SMRiP13382.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi35721. 203 interactors.
DIPiDIP-2526N.
IntActiP13382. 14 interactors.
MINTiMINT-421899.

PTM databases

iPTMnetiP13382.

Proteomic databases

MaxQBiP13382.
PRIDEiP13382.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblFungiiYNL102W; YNL102W; YNL102W.
GeneIDi855621.
KEGGisce:YNL102W.

Organism-specific databases

EuPathDBiFungiDB:YNL102W.
SGDiS000005046. POL1.

Phylogenomic databases

GeneTreeiENSGT00550000074891.
HOGENOMiHOG000163524.
InParanoidiP13382.
KOiK02320.
OMAiTDYTEVN.
OrthoDBiEOG092C038B.

Enzyme and pathway databases

BioCyciYEAST:G3O-33130-MONOMER.
BRENDAi2.7.7.7. 984.
ReactomeiR-SCE-113501. Inhibition of replication initiation of damaged DNA by RB1/E2F1.
R-SCE-113510. E2F mediated regulation of DNA replication.
R-SCE-174411. Polymerase switching on the C-strand of the telomere.
R-SCE-174430. Telomere C-strand synthesis initiation.
R-SCE-68952. DNA replication initiation.
R-SCE-68962. Activation of the pre-replicative complex.
R-SCE-69091. Polymerase switching.
R-SCE-69166. Removal of the Flap Intermediate.
R-SCE-69183. Processive synthesis on the lagging strand.
R-SCE-69205. G1/S-Specific Transcription.

Miscellaneous databases

EvolutionaryTraceiP13382.
PROiP13382.

Family and domain databases

Gene3Di3.30.420.10. 1 hit.
3.90.1600.10. 2 hits.
InterProiIPR006172. DNA-dir_DNA_pol_B.
IPR017964. DNA-dir_DNA_pol_B_CS.
IPR006133. DNA-dir_DNA_pol_B_exonuc.
IPR006134. DNA-dir_DNA_pol_B_multi_dom.
IPR024647. DNA_pol_a_cat_su_N.
IPR023211. DNA_pol_palm_dom.
IPR029702. POLA/Pol1.
IPR012337. RNaseH-like_dom.
IPR015088. Znf_DNA-dir_DNA_pol_B_alpha.
[Graphical view]
PANTHERiPTHR10322:SF21. PTHR10322:SF21. 4 hits.
PfamiPF12254. DNA_pol_alpha_N. 1 hit.
PF00136. DNA_pol_B. 1 hit.
PF03104. DNA_pol_B_exo1. 1 hit.
PF08996. zf-DNA_Pol. 1 hit.
[Graphical view]
PRINTSiPR00106. DNAPOLB.
SMARTiSM00486. POLBc. 1 hit.
[Graphical view]
SUPFAMiSSF53098. SSF53098. 2 hits.
PROSITEiPS00116. DNA_POLYMERASE_B. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiDPOA_YEAST
AccessioniPrimary (citable) accession number: P13382
Secondary accession number(s): D6W177
Entry historyi
Integrated into UniProtKB/Swiss-Prot: January 1, 1990
Last sequence update: October 1, 1996
Last modified: November 2, 2016
This is version 171 of the entry and version 2 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programFungal Protein Annotation Program

Miscellaneousi

Miscellaneous

In eukaryotes there are five DNA polymerases: alpha, beta, gamma, delta, and epsilon which are responsible for different reactions of DNA synthesis.
Present with 1050 molecules/cell in log phase SD medium.1 Publication

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome

Documents

  1. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  2. SIMILARITY comments
    Index of protein domains and families
  3. Yeast
    Yeast (Saccharomyces cerevisiae): entries, gene names and cross-references to SGD
  4. Yeast chromosome XIV
    Yeast (Saccharomyces cerevisiae) chromosome XIV: entries and gene names

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.