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Protein

DNA-directed RNA polymerase II subunit RPB9

Gene

RPB9

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

DNA-dependent RNA polymerase catalyzes the transcription of DNA into RNA using the four ribonucleoside triphosphates as substrates. Component of RNA polymerase II which synthesizes mRNA precursors and many functional non-coding RNAs. Pol II is the central component of the basal RNA polymerase II transcription machinery. It is composed of mobile elements that move relative to each other. RPB9 is part of the upper jaw surrounding the central large cleft and thought to grab the incoming DNA template. Involved in the regulation of transcription elongation. Involved in DNA repair of damage in the transcribed strand. Mediates a transcription-coupled repair (TCR) subpathway of nucleotide excision repair (NER).1 Publication

Sites

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Metal bindingi7 – 71Zinc 11 Publication3 Publications
Metal bindingi10 – 101Zinc 11 Publication3 Publications
Metal bindingi29 – 291Zinc 11 Publication3 Publications
Metal bindingi32 – 321Zinc 11 Publication3 Publications
Metal bindingi75 – 751Zinc 21 Publication3 Publications
Metal bindingi78 – 781Zinc 21 Publication3 Publications
Metal bindingi103 – 1031Zinc 21 Publication3 Publications
Metal bindingi106 – 1061Zinc 21 Publication3 Publications

Regions

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri7 – 3226C4-typeSequence analysisAdd
BLAST
Zinc fingeri71 – 11141TFIIS-typePROSITE-ProRule annotationAdd
BLAST

GO - Molecular functioni

GO - Biological processi

  • maintenance of transcriptional fidelity during DNA-templated transcription elongation from RNA polymerase II promoter Source: SGD
  • transcription, RNA-templated Source: GOC
  • transcription-coupled nucleotide-excision repair Source: SGD
  • transcription from RNA polymerase II promoter Source: SGD
  • transcription initiation from RNA polymerase II promoter Source: SGD
Complete GO annotation...

Keywords - Biological processi

DNA damage, DNA repair, Transcription

Keywords - Ligandi

Metal-binding, Zinc

Enzyme and pathway databases

BioCyciYEAST:G3O-30573-MONOMER.
ReactomeiR-SCE-113418. Formation of the Early Elongation Complex.
R-SCE-674695. RNA Polymerase II Pre-transcription Events.
R-SCE-6781823. Formation of TC-NER Pre-Incision Complex.
R-SCE-6782135. Dual incision in TC-NER.
R-SCE-6782210. Gap-filling DNA repair synthesis and ligation in TC-NER.
R-SCE-6796648. TP53 Regulates Transcription of DNA Repair Genes.
R-SCE-72086. mRNA Capping.
R-SCE-72165. mRNA Splicing - Minor Pathway.
R-SCE-73776. RNA Polymerase II Promoter Escape.
R-SCE-73779. RNA Polymerase II Transcription Pre-Initiation And Promoter Opening.
R-SCE-75953. RNA Polymerase II Transcription Initiation.
R-SCE-76042. RNA Polymerase II Transcription Initiation And Promoter Clearance.
R-SCE-77075. RNA Pol II CTD phosphorylation and interaction with CE.

Names & Taxonomyi

Protein namesi
Recommended name:
DNA-directed RNA polymerase II subunit RPB9
Short name:
RNA polymerase II subunit B9
Alternative name(s):
B12.6
DNA-directed RNA polymerase II 14.2 kDa polypeptide
DNA-directed RNA polymerase II subunit 9
Gene namesi
Name:RPB9
Ordered Locus Names:YGL070C
OrganismiSaccharomyces cerevisiae (strain ATCC 204508 / S288c) (Baker's yeast)
Taxonomic identifieri559292 [NCBI]
Taxonomic lineageiEukaryotaFungiDikaryaAscomycotaSaccharomycotinaSaccharomycetesSaccharomycetalesSaccharomycetaceaeSaccharomyces
Proteomesi
  • UP000002311 Componenti: Chromosome VII

Organism-specific databases

EuPathDBiFungiDB:YGL070C.
SGDiS000003038. RPB9.

Subcellular locationi

  • Nucleusnucleolus By similarity

GO - Cellular componenti

  • DNA-directed RNA polymerase II, core complex Source: SGD
  • nucleolus Source: UniProtKB-SubCell
Complete GO annotation...

Keywords - Cellular componenti

DNA-directed RNA polymerase, Nucleus

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Chaini1 – 122122DNA-directed RNA polymerase II subunit RPB9PRO_0000121474Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Modified residuei40 – 401PhosphoserineCombined sources

Keywords - PTMi

Phosphoprotein

PTM databases

iPTMnetiP27999.

Interactioni

Subunit structurei

Component of the RNA polymerase II (Pol II) complex consisting of 12 subunits.12 Publications

Protein-protein interaction databases

BioGridi33178. 81 interactions.
DIPiDIP-610N.
IntActiP27999. 18 interactions.
MINTiMINT-474033.

Structurei

Secondary structure

1
122
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi8 – 103Combined sources
Beta strandi15 – 195Combined sources
Turni20 – 234Combined sources
Beta strandi24 – 285Combined sources
Beta strandi30 – 334Combined sources
Beta strandi35 – 373Combined sources
Beta strandi41 – 499Combined sources
Turni52 – 576Combined sources
Helixi62 – 643Combined sources
Beta strandi66 – 683Combined sources
Turni76 – 783Combined sources
Beta strandi83 – 875Combined sources
Beta strandi92 – 943Combined sources
Beta strandi99 – 1035Combined sources
Turni104 – 1063Combined sources
Beta strandi109 – 1113Combined sources
Beta strandi114 – 1163Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1I3QX-ray3.10I1-122[»]
1I50X-ray2.80I1-122[»]
1I6HX-ray3.30I1-122[»]
1K83X-ray2.80I1-122[»]
1NIKX-ray4.10I1-122[»]
1NT9X-ray4.20I1-122[»]
1PQVX-ray3.80I1-122[»]
1R5UX-ray4.50I1-122[»]
1R9SX-ray4.25I1-122[»]
1R9TX-ray3.50I1-122[»]
1SFOX-ray3.61I1-122[»]
1TWAX-ray3.20I1-122[»]
1TWCX-ray3.00I1-122[»]
1TWFX-ray2.30I1-122[»]
1TWGX-ray3.30I1-122[»]
1TWHX-ray3.40I1-122[»]
1WCMX-ray3.80I1-122[»]
1Y1VX-ray3.80I1-122[»]
1Y1WX-ray4.00I1-122[»]
1Y1YX-ray4.00I1-122[»]
1Y77X-ray4.50I1-122[»]
2B63X-ray3.80I1-122[»]
2B8KX-ray4.15I1-122[»]
2E2HX-ray3.95I1-122[»]
2E2IX-ray3.41I1-122[»]
2E2JX-ray3.50I1-122[»]
2JA5X-ray3.80I1-122[»]
2JA6X-ray4.00I1-122[»]
2JA7X-ray3.80I/U1-122[»]
2JA8X-ray3.80I1-122[»]
2NVQX-ray2.90I1-122[»]
2NVTX-ray3.36I1-122[»]
2NVXX-ray3.60I1-122[»]
2NVYX-ray3.40I1-122[»]
2NVZX-ray4.30I1-122[»]
2R7ZX-ray3.80I1-122[»]
2R92X-ray3.80I1-122[»]
2R93X-ray4.00I1-122[»]
2VUMX-ray3.40I1-122[»]
2YU9X-ray3.40I1-122[»]
3CQZX-ray2.80I1-122[»]
3FKIX-ray3.88I1-122[»]
3GTGX-ray3.78I1-122[»]
3GTJX-ray3.42I1-122[»]
3GTKX-ray3.80I1-122[»]
3GTLX-ray3.38I1-122[»]
3GTMX-ray3.80I1-122[»]
3GTOX-ray4.00I1-122[»]
3GTPX-ray3.90I1-122[»]
3GTQX-ray3.80I1-122[»]
3H3VX-ray4.00J1-122[»]
3HOUX-ray3.20I/U1-122[»]
3HOVX-ray3.50I1-122[»]
3HOWX-ray3.60I1-122[»]
3HOXX-ray3.65I1-122[»]
3HOYX-ray3.40I1-122[»]
3HOZX-ray3.65I1-122[»]
3I4MX-ray3.70I1-122[»]
3I4NX-ray3.90I1-122[»]
3J0Kelectron microscopy36.00I1-122[»]
3J1Nelectron microscopy16.00I1-122[»]
3K1FX-ray4.30I1-122[»]
3K7AX-ray3.80I1-122[»]
3M3YX-ray3.18I1-122[»]
3M4OX-ray3.57I1-122[»]
3PO2X-ray3.30I1-122[»]
3PO3X-ray3.30I1-122[»]
3QT1X-ray4.30I1-87[»]
3RZDX-ray3.30I1-122[»]
3RZOX-ray3.00I1-122[»]
3S14X-ray2.85I1-122[»]
3S15X-ray3.30I1-122[»]
3S16X-ray3.24I1-122[»]
3S17X-ray3.20I1-122[»]
3S1MX-ray3.13I1-122[»]
3S1NX-ray3.10I1-122[»]
3S1QX-ray3.30I1-122[»]
3S1RX-ray3.20I1-122[»]
3S2DX-ray3.20I1-122[»]
3S2HX-ray3.30I1-122[»]
4A3BX-ray3.50I1-122[»]
4A3CX-ray3.50I1-122[»]
4A3DX-ray3.40I1-122[»]
4A3EX-ray3.40I1-122[»]
4A3FX-ray3.50I1-122[»]
4A3GX-ray3.50I1-122[»]
4A3IX-ray3.80I1-122[»]
4A3JX-ray3.70I1-122[»]
4A3KX-ray3.50I1-122[»]
4A3LX-ray3.50I1-122[»]
4A3MX-ray3.90I1-122[»]
4A93X-ray3.40I1-122[»]
4BBRX-ray3.40I1-122[»]
4BBSX-ray3.60I1-122[»]
4BXXX-ray3.28I1-122[»]
4BXZX-ray4.80I1-122[»]
4BY1X-ray3.60I1-122[»]
4BY7X-ray3.15I1-122[»]
4V1Melectron microscopy6.60I1-122[»]
4V1Nelectron microscopy7.80I1-122[»]
4V1Oelectron microscopy9.70I1-122[»]
4X67X-ray4.10I1-122[»]
4X6AX-ray3.96I1-122[»]
4Y52X-ray3.50I1-122[»]
4Y7NX-ray3.30I1-122[»]
5C3EX-ray3.70I1-122[»]
5C44X-ray3.95I1-120[»]
5C4AX-ray4.20I1-122[»]
5C4JX-ray4.00I1-122[»]
5C4XX-ray4.00I1-122[»]
5FMFelectron microscopy6.00I2-120[»]
5FYWelectron microscopy4.35I1-122[»]
5FZ5electron microscopy8.80I1-122[»]
5IP7X-ray3.52I2-120[»]
5IP9X-ray3.90I2-120[»]
ProteinModelPortaliP27999.
SMRiP27999. Positions 1-122.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP27999.

Family & Domainsi

Sequence similaritiesi

Contains 1 TFIIS-type zinc finger.PROSITE-ProRule annotation

Zinc finger

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Zinc fingeri7 – 3226C4-typeSequence analysisAdd
BLAST
Zinc fingeri71 – 11141TFIIS-typePROSITE-ProRule annotationAdd
BLAST

Keywords - Domaini

Zinc-finger

Phylogenomic databases

GeneTreeiENSGT00550000075063.
HOGENOMiHOG000228134.
InParanoidiP27999.
KOiK03017.
OMAiTLAHAKM.
OrthoDBiEOG092C59RA.

Family and domain databases

InterProiIPR019761. DNA-dir_RNA_pol-M_15_CS.
IPR001529. DNA-dir_RNA_pol_M/15kDasu.
IPR012164. Rpa12/Rpb9/Rpc10/TFS.
IPR001222. Znf_TFIIS.
[Graphical view]
PfamiPF02150. RNA_POL_M_15KD. 1 hit.
PF01096. TFIIS_C. 1 hit.
[Graphical view]
PIRSFiPIRSF005586. RNApol_RpoM. 1 hit.
SMARTiSM00661. RPOL9. 1 hit.
SM00440. ZnF_C2C2. 1 hit.
[Graphical view]
PROSITEiPS01030. RNA_POL_M_15KD. 1 hit.
PS00466. ZF_TFIIS_1. 1 hit.
PS51133. ZF_TFIIS_2. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

P27999-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MTTFRFCRDC NNMLYPREDK ENNRLLFECR TCSYVEEAGS PLVYRHELIT
60 70 80 90 100
NIGETAGVVQ DIGSDPTLPR SDRECPKCHS RENVFFQSQQ RRKDTSMVLF
110 120
FVCLSCSHIF TSDQKNKRTQ FS
Length:122
Mass (Da):14,288
Last modified:August 1, 1992 - v1
Checksum:iA80D69678A722881
GO

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M73060 Genomic DNA. Translation: AAA34997.1.
Z72592 Genomic DNA. Translation: CAA96774.1.
AY557799 Genomic DNA. Translation: AAS56125.1.
BK006941 Genomic DNA. Translation: DAA08033.1.
PIRiA41016. RNBY29.
RefSeqiNP_011445.1. NM_001180935.1.

Genome annotation databases

EnsemblFungiiYGL070C; YGL070C; YGL070C.
GeneIDi852810.
KEGGisce:YGL070C.

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
M73060 Genomic DNA. Translation: AAA34997.1.
Z72592 Genomic DNA. Translation: CAA96774.1.
AY557799 Genomic DNA. Translation: AAS56125.1.
BK006941 Genomic DNA. Translation: DAA08033.1.
PIRiA41016. RNBY29.
RefSeqiNP_011445.1. NM_001180935.1.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1I3QX-ray3.10I1-122[»]
1I50X-ray2.80I1-122[»]
1I6HX-ray3.30I1-122[»]
1K83X-ray2.80I1-122[»]
1NIKX-ray4.10I1-122[»]
1NT9X-ray4.20I1-122[»]
1PQVX-ray3.80I1-122[»]
1R5UX-ray4.50I1-122[»]
1R9SX-ray4.25I1-122[»]
1R9TX-ray3.50I1-122[»]
1SFOX-ray3.61I1-122[»]
1TWAX-ray3.20I1-122[»]
1TWCX-ray3.00I1-122[»]
1TWFX-ray2.30I1-122[»]
1TWGX-ray3.30I1-122[»]
1TWHX-ray3.40I1-122[»]
1WCMX-ray3.80I1-122[»]
1Y1VX-ray3.80I1-122[»]
1Y1WX-ray4.00I1-122[»]
1Y1YX-ray4.00I1-122[»]
1Y77X-ray4.50I1-122[»]
2B63X-ray3.80I1-122[»]
2B8KX-ray4.15I1-122[»]
2E2HX-ray3.95I1-122[»]
2E2IX-ray3.41I1-122[»]
2E2JX-ray3.50I1-122[»]
2JA5X-ray3.80I1-122[»]
2JA6X-ray4.00I1-122[»]
2JA7X-ray3.80I/U1-122[»]
2JA8X-ray3.80I1-122[»]
2NVQX-ray2.90I1-122[»]
2NVTX-ray3.36I1-122[»]
2NVXX-ray3.60I1-122[»]
2NVYX-ray3.40I1-122[»]
2NVZX-ray4.30I1-122[»]
2R7ZX-ray3.80I1-122[»]
2R92X-ray3.80I1-122[»]
2R93X-ray4.00I1-122[»]
2VUMX-ray3.40I1-122[»]
2YU9X-ray3.40I1-122[»]
3CQZX-ray2.80I1-122[»]
3FKIX-ray3.88I1-122[»]
3GTGX-ray3.78I1-122[»]
3GTJX-ray3.42I1-122[»]
3GTKX-ray3.80I1-122[»]
3GTLX-ray3.38I1-122[»]
3GTMX-ray3.80I1-122[»]
3GTOX-ray4.00I1-122[»]
3GTPX-ray3.90I1-122[»]
3GTQX-ray3.80I1-122[»]
3H3VX-ray4.00J1-122[»]
3HOUX-ray3.20I/U1-122[»]
3HOVX-ray3.50I1-122[»]
3HOWX-ray3.60I1-122[»]
3HOXX-ray3.65I1-122[»]
3HOYX-ray3.40I1-122[»]
3HOZX-ray3.65I1-122[»]
3I4MX-ray3.70I1-122[»]
3I4NX-ray3.90I1-122[»]
3J0Kelectron microscopy36.00I1-122[»]
3J1Nelectron microscopy16.00I1-122[»]
3K1FX-ray4.30I1-122[»]
3K7AX-ray3.80I1-122[»]
3M3YX-ray3.18I1-122[»]
3M4OX-ray3.57I1-122[»]
3PO2X-ray3.30I1-122[»]
3PO3X-ray3.30I1-122[»]
3QT1X-ray4.30I1-87[»]
3RZDX-ray3.30I1-122[»]
3RZOX-ray3.00I1-122[»]
3S14X-ray2.85I1-122[»]
3S15X-ray3.30I1-122[»]
3S16X-ray3.24I1-122[»]
3S17X-ray3.20I1-122[»]
3S1MX-ray3.13I1-122[»]
3S1NX-ray3.10I1-122[»]
3S1QX-ray3.30I1-122[»]
3S1RX-ray3.20I1-122[»]
3S2DX-ray3.20I1-122[»]
3S2HX-ray3.30I1-122[»]
4A3BX-ray3.50I1-122[»]
4A3CX-ray3.50I1-122[»]
4A3DX-ray3.40I1-122[»]
4A3EX-ray3.40I1-122[»]
4A3FX-ray3.50I1-122[»]
4A3GX-ray3.50I1-122[»]
4A3IX-ray3.80I1-122[»]
4A3JX-ray3.70I1-122[»]
4A3KX-ray3.50I1-122[»]
4A3LX-ray3.50I1-122[»]
4A3MX-ray3.90I1-122[»]
4A93X-ray3.40I1-122[»]
4BBRX-ray3.40I1-122[»]
4BBSX-ray3.60I1-122[»]
4BXXX-ray3.28I1-122[»]
4BXZX-ray4.80I1-122[»]
4BY1X-ray3.60I1-122[»]
4BY7X-ray3.15I1-122[»]
4V1Melectron microscopy6.60I1-122[»]
4V1Nelectron microscopy7.80I1-122[»]
4V1Oelectron microscopy9.70I1-122[»]
4X67X-ray4.10I1-122[»]
4X6AX-ray3.96I1-122[»]
4Y52X-ray3.50I1-122[»]
4Y7NX-ray3.30I1-122[»]
5C3EX-ray3.70I1-122[»]
5C44X-ray3.95I1-120[»]
5C4AX-ray4.20I1-122[»]
5C4JX-ray4.00I1-122[»]
5C4XX-ray4.00I1-122[»]
5FMFelectron microscopy6.00I2-120[»]
5FYWelectron microscopy4.35I1-122[»]
5FZ5electron microscopy8.80I1-122[»]
5IP7X-ray3.52I2-120[»]
5IP9X-ray3.90I2-120[»]
ProteinModelPortaliP27999.
SMRiP27999. Positions 1-122.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi33178. 81 interactions.
DIPiDIP-610N.
IntActiP27999. 18 interactions.
MINTiMINT-474033.

PTM databases

iPTMnetiP27999.

Protocols and materials databases

Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsemblFungiiYGL070C; YGL070C; YGL070C.
GeneIDi852810.
KEGGisce:YGL070C.

Organism-specific databases

EuPathDBiFungiDB:YGL070C.
SGDiS000003038. RPB9.

Phylogenomic databases

GeneTreeiENSGT00550000075063.
HOGENOMiHOG000228134.
InParanoidiP27999.
KOiK03017.
OMAiTLAHAKM.
OrthoDBiEOG092C59RA.

Enzyme and pathway databases

BioCyciYEAST:G3O-30573-MONOMER.
ReactomeiR-SCE-113418. Formation of the Early Elongation Complex.
R-SCE-674695. RNA Polymerase II Pre-transcription Events.
R-SCE-6781823. Formation of TC-NER Pre-Incision Complex.
R-SCE-6782135. Dual incision in TC-NER.
R-SCE-6782210. Gap-filling DNA repair synthesis and ligation in TC-NER.
R-SCE-6796648. TP53 Regulates Transcription of DNA Repair Genes.
R-SCE-72086. mRNA Capping.
R-SCE-72165. mRNA Splicing - Minor Pathway.
R-SCE-73776. RNA Polymerase II Promoter Escape.
R-SCE-73779. RNA Polymerase II Transcription Pre-Initiation And Promoter Opening.
R-SCE-75953. RNA Polymerase II Transcription Initiation.
R-SCE-76042. RNA Polymerase II Transcription Initiation And Promoter Clearance.
R-SCE-77075. RNA Pol II CTD phosphorylation and interaction with CE.

Miscellaneous databases

EvolutionaryTraceiP27999.
PROiP27999.

Family and domain databases

InterProiIPR019761. DNA-dir_RNA_pol-M_15_CS.
IPR001529. DNA-dir_RNA_pol_M/15kDasu.
IPR012164. Rpa12/Rpb9/Rpc10/TFS.
IPR001222. Znf_TFIIS.
[Graphical view]
PfamiPF02150. RNA_POL_M_15KD. 1 hit.
PF01096. TFIIS_C. 1 hit.
[Graphical view]
PIRSFiPIRSF005586. RNApol_RpoM. 1 hit.
SMARTiSM00661. RPOL9. 1 hit.
SM00440. ZnF_C2C2. 1 hit.
[Graphical view]
PROSITEiPS01030. RNA_POL_M_15KD. 1 hit.
PS00466. ZF_TFIIS_1. 1 hit.
PS51133. ZF_TFIIS_2. 1 hit.
[Graphical view]
ProtoNetiSearch...

Entry informationi

Entry nameiRPB9_YEAST
AccessioniPrimary (citable) accession number: P27999
Secondary accession number(s): D6VU72
Entry historyi
Integrated into UniProtKB/Swiss-Prot: August 1, 1992
Last sequence update: August 1, 1992
Last modified: September 7, 2016
This is version 179 of the entry and version 1 of the sequence. [Complete history]
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programFungal Protein Annotation Program

Miscellaneousi

Miscellaneous

Present with 2440 molecules/cell in log phase SD medium.1 Publication

Keywords - Technical termi

3D-structure, Complete proteome, Direct protein sequencing, 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 VII
    Yeast (Saccharomyces cerevisiae) chromosome VII: 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.