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

HLA class II histocompatibility antigen, DR alpha chain

Gene

HLA-DRA

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

Functioni

Binds peptides derived from antigens that access the endocytic route of antigen presenting cells (APC) and presents them on the cell surface for recognition by the CD4 T-cells. The peptide binding cleft accommodates peptides of 10-30 residues. The peptides presented by MHC class II molecules are generated mostly by degradation of proteins that access the endocytic route, where they are processed by lysosomal proteases and other hydrolases. Exogenous antigens that have been endocytosed by the APC are thus readily available for presentation via MHC II molecules, and for this reason this antigen presentation pathway is usually referred to as exogenous. As membrane proteins on their way to degradation in lysosomes as part of their normal turn-over are also contained in the endosomal/lysosomal compartments, exogenous antigens must compete with those derived from endogenous components. Autophagy is also a source of endogenous peptides, autophagosomes constitutively fuse with MHC class II loading compartments. In addition to APCs, other cells of the gastrointestinal tract, such as epithelial cells, express MHC class II molecules and CD74 and act as APCs, which is an unusual trait of the GI tract. To produce a MHC class II molecule that presents an antigen, three MHC class II molecules (heterodimers of an alpha and a beta chain) associate with a CD74 trimer in the ER to form a heterononamer. Soon after the entry of this complex into the endosomal/lysosomal system where antigen processing occurs, CD74 undergoes a sequential degradation by various proteases, including CTSS and CTSL, leaving a small fragment termed CLIP (class-II-associated invariant chain peptide). The removal of CLIP is facilitated by HLA-DM via direct binding to the alpha-beta-CLIP complex so that CLIP is released. HLA-DM stabilizes MHC class II molecules until primary high affinity antigenic peptides are bound. The MHC II molecule bound to a peptide is then transported to the cell membrane surface. In B-cells, the interaction between HLA-DM and MHC class II molecules is regulated by HLA-DO. Primary dendritic cells (DCs) also to express HLA-DO. Lysosomal microenvironment has been implicated in the regulation of antigen loading into MHC II molecules, increased acidification produces increased proteolysis and efficient peptide loading.

GO - Molecular functioni

  • MHC class II protein complex binding Source: UniProtKB
  • MHC class II receptor activity Source: UniProtKB
  • peptide antigen binding Source: UniProtKB

GO - Biological processi

Complete GO annotation...

Keywords - Biological processi

Host-virus interaction, Immunity

Enzyme and pathway databases

ReactomeiREACT_121399. MHC class II antigen presentation.
REACT_12555. Downstream TCR signaling.
REACT_12582. Phosphorylation of CD3 and TCR zeta chains.
REACT_12596. Translocation of ZAP-70 to Immunological synapse.
REACT_12623. Generation of second messenger molecules.
REACT_19324. PD-1 signaling.
REACT_25078. Interferon gamma signaling.

Names & Taxonomyi

Protein namesi
Recommended name:
HLA class II histocompatibility antigen, DR alpha chain
Alternative name(s):
MHC class II antigen DRA
Gene namesi
Name:HLA-DRA
Synonyms:HLA-DRA1
OrganismiHomo sapiens (Human)
Taxonomic identifieri9606 [NCBI]
Taxonomic lineageiEukaryotaMetazoaChordataCraniataVertebrataEuteleostomiMammaliaEutheriaEuarchontogliresPrimatesHaplorrhiniCatarrhiniHominidaeHomo
ProteomesiUP000005640 Componentsi: Chromosome 6, Unplaced

Organism-specific databases

HGNCiHGNC:4947. HLA-DRA.

Subcellular locationi

Topology

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Topological domaini26 – 216191ExtracellularSequence AnalysisAdd
BLAST
Transmembranei217 – 23923HelicalSequence AnalysisAdd
BLAST
Topological domaini240 – 25415CytoplasmicSequence AnalysisAdd
BLAST

GO - Cellular componenti

  • cell surface Source: UniProtKB
  • clathrin-coated endocytic vesicle membrane Source: Reactome
  • endocytic vesicle membrane Source: Reactome
  • ER to Golgi transport vesicle membrane Source: Reactome
  • extracellular exosome Source: UniProtKB
  • Golgi membrane Source: Reactome
  • integral component of lumenal side of endoplasmic reticulum membrane Source: Reactome
  • integral component of plasma membrane Source: UniProtKB
  • late endosome membrane Source: UniProtKB
  • lysosomal membrane Source: UniProtKB
  • lysosome Source: MGI
  • MHC class II protein complex Source: UniProtKB
  • plasma membrane Source: MGI
  • trans-Golgi network membrane Source: Reactome
  • transport vesicle membrane Source: Reactome
Complete GO annotation...

Keywords - Cellular componenti

Cell membrane, Endoplasmic reticulum, Endosome, Golgi apparatus, Lysosome, Membrane, MHC II

Pathology & Biotechi

Mutagenesis

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Mutagenesisi244 – 2441K → R: Almost no change in down-regulation of MHC class II. No ubiquitination and complete loss of down-regulation of MHC class II; when associated with 'R-254' of HLA-DRB. 1 Publication

Organism-specific databases

MIMi610424. phenotype.
Orphaneti505. Graham Little-Piccardi-Lassueur syndrome.
PharmGKBiPA35071.

Protein family/group databases

Allergomei8362. Hom s HLA-DR-alpha.

Polymorphism and mutation databases

BioMutaiHLA-DRA.
DMDMi122206.

PTM / Processingi

Molecule processing

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Signal peptidei1 – 25253 PublicationsAdd
BLAST
Chaini26 – 254229HLA class II histocompatibility antigen, DR alpha chainPRO_0000018947Add
BLAST

Amino acid modifications

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Glycosylationi103 – 1031N-linked (GlcNAc...)2 Publications
Disulfide bondi132 ↔ 188PROSITE-ProRule annotation5 Publications
Glycosylationi143 – 1431N-linked (GlcNAc...)2 Publications
Cross-linki244 – 244Glycyl lysine isopeptide (Lys-Gly) (interchain with G-Cter in ubiquitin)1 Publication

Post-translational modificationi

Ubiquitinated by MARCH1 or MARCH8 at Lys-244 leading to down-regulation of MHC class II. When associated with ubiquitination of the beta subunit of HLA-DR: HLA-DRB4 'Lys-254', the down-regulation of MHC class II may be highly effective.1 Publication

Keywords - PTMi

Disulfide bond, Glycoprotein, Isopeptide bond, Ubl conjugation

Proteomic databases

MaxQBiP01903.
PaxDbiP01903.
PRIDEiP01903.

PTM databases

PhosphoSiteiP01903.

Expressioni

Gene expression databases

BgeeiP01903.
CleanExiHS_HLA-DRA.
ExpressionAtlasiP01903. baseline and differential.
GenevisibleiP01903. HS.

Organism-specific databases

HPAiCAB002798.
CAB015402.
HPA050162.
HPA053176.

Interactioni

Subunit structurei

Heterodimer of an alpha and a beta subunit; also referred as MHC class II molecule. In the endoplasmic reticulum (ER) it forms a heterononamer; 3 MHC class II molecules bind to a CD74 homotrimer (also known as invariant chain or HLA class II histocompatibility antigen gamma chain). In the endosomal/lysosomal system; CD74 undergoes sequential degradation by various proteases; leaving a small fragment termed CLIP on each MHC class II molecule. MHC class II molecule interacts with HLA_DM, and HLA_DO in B-cells, in order to release CLIP and facilitate the binding of antigenic peptides. Interacts with Epstein-Barr virus BZLF2/gp42.8 Publications

Protein-protein interaction databases

BioGridi109367. 39 interactions.
DIPiDIP-6063N.
IntActiP01903. 10 interactions.
MINTiMINT-203259.

Structurei

Secondary structure

1
254
Legend: HelixTurnBeta strand
Show more details
Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Beta strandi30 – 4011Combined sources
Turni41 – 433Combined sources
Beta strandi44 – 518Combined sources
Beta strandi54 – 607Combined sources
Turni61 – 644Combined sources
Beta strandi65 – 706Combined sources
Helixi71 – 755Combined sources
Helixi82 – 10120Combined sources
Turni102 – 1043Combined sources
Beta strandi113 – 1208Combined sources
Beta strandi124 – 1263Combined sources
Beta strandi128 – 14013Combined sources
Beta strandi143 – 1486Combined sources
Beta strandi151 – 1533Combined sources
Beta strandi155 – 1595Combined sources
Beta strandi170 – 1789Combined sources
Beta strandi185 – 1917Combined sources
Beta strandi195 – 1973Combined sources
Beta strandi199 – 2046Combined sources

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1A6AX-ray2.75A30-205[»]
1AQDX-ray2.45A/D/G/J26-217[»]
1BX2X-ray2.60A/D27-206[»]
1D5MX-ray2.00A26-206[»]
1D5XX-ray2.45A26-206[»]
1D5ZX-ray2.00A26-206[»]
1D6EX-ray2.45A26-206[»]
1DLHX-ray2.80A/D28-207[»]
1FV1X-ray1.90A/D26-206[»]
1FYTX-ray2.60A26-206[»]
1H15X-ray3.10A/D26-207[»]
1HQRX-ray3.20A26-206[»]
1HXYX-ray2.60A26-207[»]
1J8HX-ray2.40A26-206[»]
1JWMX-ray2.70A26-207[»]
1JWSX-ray2.60A26-207[»]
1JWUX-ray2.30A26-207[»]
1KG0X-ray2.65A28-207[»]
1KLGX-ray2.40A29-205[»]
1KLUX-ray1.93A29-207[»]
1LO5X-ray3.20A26-207[»]
1PYWX-ray2.10A26-207[»]
1R5IX-ray2.60A/E26-206[»]
1SEBX-ray2.70A/E26-206[»]
1SJEX-ray2.45A28-207[»]
1SJHX-ray2.25A28-207[»]
1T5WX-ray2.40A/D27-206[»]
1T5XX-ray2.50A27-207[»]
1YMMX-ray3.50A26-216[»]
1ZGLX-ray2.80A/D/G/J26-206[»]
2FSEX-ray3.10A/C29-205[»]
2G9HX-ray2.00A26-207[»]
2IAMX-ray2.80A26-207[»]
2IANX-ray2.80A/F/K/P26-207[»]
2ICWX-ray2.41A/D28-206[»]
2IPKX-ray2.30A26-207[»]
2OJEX-ray3.00A/E27-206[»]
2Q6WX-ray2.25A/D26-207[»]
2SEBX-ray2.50A26-206[»]
2WBJX-ray3.00A/E26-218[»]
2XN9X-ray2.30D26-207[»]
3C5JX-ray1.80A26-206[»]
3L6FX-ray2.10A26-207[»]
3O6FX-ray2.80A/E26-207[»]
3PDOX-ray1.95A26-217[»]
3PGCX-ray2.66A/D26-217[»]
3PGDX-ray2.72A/D26-217[»]
3QXAX-ray2.71A/D26-207[»]
3QXDX-ray2.30A/D26-207[»]
3S4SX-ray2.40A/D26-207[»]
3S5LX-ray2.10A/D26-207[»]
3T0EX-ray4.00A26-207[»]
4AENX-ray2.20A26-217[»]
4AH2X-ray2.36A26-217[»]
4C56X-ray2.90D/J26-207[»]
4E41X-ray2.60A/F26-207[»]
4FQXX-ray2.60A26-216[»]
4GBXX-ray3.00A26-216[»]
4H1LX-ray3.30A/D28-205[»]
4H25X-ray2.20A/D28-207[»]
4H26X-ray2.50A/D28-206[»]
4I5BX-ray2.12A/D27-213[»]
4IS6X-ray2.50A26-207[»]
4MCYX-ray2.30A26-206[»]
4MCZX-ray2.41A26-206[»]
4MD0X-ray2.19A26-206[»]
4MD4X-ray1.95A26-206[»]
4MD5X-ray1.65A26-206[»]
4MDIX-ray2.00A26-206[»]
4MDJX-ray1.70A26-206[»]
4OV5X-ray2.20A/D/G/J/M/P26-207[»]
ProteinModelPortaliP01903.
SMRiP01903. Positions 28-206.
ModBaseiSearch...
MobiDBiSearch...

Miscellaneous databases

EvolutionaryTraceiP01903.

Family & Domainsi

Domains and Repeats

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Domaini112 – 20493Ig-like C1-typeAdd
BLAST

Region

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Regioni26 – 10984Alpha-1Add
BLAST
Regioni110 – 20394Alpha-2Add
BLAST
Regioni204 – 21613Connecting peptideAdd
BLAST

Sequence similaritiesi

Belongs to the MHC class II family.Curated

Keywords - Domaini

Signal, Transmembrane, Transmembrane helix

Phylogenomic databases

eggNOGiNOG44736.
HOVERGENiHBG006862.
InParanoidiP01903.
KOiK06752.
OMAiMIKRSNH.
PhylomeDBiP01903.
TreeFamiTF333797.

Family and domain databases

Gene3Di2.60.40.10. 1 hit.
3.10.320.10. 1 hit.
InterProiIPR007110. Ig-like_dom.
IPR013783. Ig-like_fold.
IPR003006. Ig/MHC_CS.
IPR003597. Ig_C1-set.
IPR011162. MHC_I/II-like_Ag-recog.
IPR014745. MHC_II_a/b_N.
IPR001003. MHC_II_a_N.
[Graphical view]
PfamiPF07654. C1-set. 1 hit.
PF00993. MHC_II_alpha. 1 hit.
[Graphical view]
SMARTiSM00407. IGc1. 1 hit.
SM00920. MHC_II_alpha. 1 hit.
[Graphical view]
SUPFAMiSSF54452. SSF54452. 1 hit.
PROSITEiPS50835. IG_LIKE. 1 hit.
PS00290. IG_MHC. 1 hit.
[Graphical view]

Sequencei

Sequence statusi: Complete.

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

P01903-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MAISGVPVLG FFIIAVLMSA QESWAIKEEH VIIQAEFYLN PDQSGEFMFD
60 70 80 90 100
FDGDEIFHVD MAKKETVWRL EEFGRFASFE AQGALANIAV DKANLEIMTK
110 120 130 140 150
RSNYTPITNV PPEVTVLTNS PVELREPNVL ICFIDKFTPP VVNVTWLRNG
160 170 180 190 200
KPVTTGVSET VFLPREDHLF RKFHYLPFLP STEDVYDCRV EHWGLDEPLL
210 220 230 240 250
KHWEFDAPSP LPETTENVVC ALGLTVGLVG IIIGTIFIIK GVRKSNAAER

RGPL
Length:254
Mass (Da):28,607
Last modified:July 21, 1986 - v1
Checksum:i3CD1CDBA952B2350
GO

Sequence cautioni

The sequence CAA25076.1 differs from that shown. Reason: Erroneous initiation. Translation N-terminally extended.Curated

Experimental Info

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Sequence conflicti28 – 292EE → AD AA sequence (PubMed:6812963).Curated
Sequence conflicti33 – 331I → T AA sequence (PubMed:6812963).Curated
Sequence conflicti34 – 352QA → YP AA sequence (PubMed:6812963).Curated
Sequence conflicti48 – 481M → Q AA sequence (PubMed:6812963).Curated
Sequence conflicti54 – 541D → T AA sequence (PubMed:6812963).Curated
Sequence conflicti59 – 591V → Y AA sequence (PubMed:6600932).Curated
Sequence conflicti64 – 641K → L AA sequence (PubMed:6600932).Curated
Sequence conflicti67 – 671V → A AA sequence (PubMed:6955253).Curated
Sequence conflicti69 – 691R → L AA sequence (PubMed:6600932).Curated
Sequence conflicti75 – 751R → P AA sequence (PubMed:6600932).Curated
Sequence conflicti78 – 781S → D AA sequence (PubMed:6600932).Curated
Sequence conflicti149 – 1491N → E AA sequence (PubMed:6955253).Curated

Polymorphismi

The following alleles of DRA are known: DRA*01:01 and DRA*01:02. The sequence shown is that of DRA*01:01.
Genetic variations in HLA-DRA influence susceptibility to hepatitis B virus (HBV) infection [MIMi:610424].

Natural variant

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifierActions
Natural varianti16 – 161V → L.
Corresponds to variant rs16822586 [ dbSNP | Ensembl ].
VAR_035241
Natural varianti242 – 2421V → L in allele DRA*01:02.
Corresponds to variant rs7192 [ dbSNP | Ensembl ].
VAR_004399

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J00194 mRNA. Translation: AAA36275.1.
K01171 mRNA. Translation: AAA59785.1.
X00274 Genomic DNA. Translation: CAA25076.1. Different initiation.
J00204, J00203 Genomic DNA. Translation: AAA36302.1.
M60334 mRNA. Translation: AAA59783.1.
CR457013 mRNA. Translation: CAG33294.1.
AL662796 Genomic DNA. Translation: CAI18266.1.
AL670296 Genomic DNA. Translation: CAI17571.1.
AL935032 Genomic DNA. Translation: CAI18476.1.
BX120007 Genomic DNA. Translation: CAM26203.1.
Z84814 Genomic DNA. Translation: CAB06609.1.
CH471081 Genomic DNA. Translation: EAX03630.1.
BC032350 mRNA. Translation: AAH32350.1.
BC071659 mRNA. Translation: AAH71659.1.
V00523 mRNA. Translation: CAA23782.1.
J00201 Genomic DNA. Translation: AAA36301.1.
AF481359 Genomic DNA. Translation: AAO23887.1.
CCDSiCCDS4750.1.
PIRiA93952. HLHUDA.
RefSeqiNP_061984.2. NM_019111.4.
UniGeneiHs.520048.

Genome annotation databases

EnsembliENST00000383127; ENSP00000372608; ENSG00000227993.
ENST00000383259; ENSP00000372746; ENSG00000206308.
ENST00000395388; ENSP00000378786; ENSG00000204287.
ENST00000411524; ENSP00000405295; ENSG00000234794.
ENST00000414698; ENSP00000402951; ENSG00000230726.
ENST00000416883; ENSP00000410443; ENSG00000228987.
ENST00000442960; ENSP00000404533; ENSG00000226260.
GeneIDi3122.
KEGGihsa:3122.
UCSCiuc003obh.3. human.

Keywords - Coding sequence diversityi

Polymorphism

Cross-referencesi

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
J00194 mRNA. Translation: AAA36275.1.
K01171 mRNA. Translation: AAA59785.1.
X00274 Genomic DNA. Translation: CAA25076.1. Different initiation.
J00204, J00203 Genomic DNA. Translation: AAA36302.1.
M60334 mRNA. Translation: AAA59783.1.
CR457013 mRNA. Translation: CAG33294.1.
AL662796 Genomic DNA. Translation: CAI18266.1.
AL670296 Genomic DNA. Translation: CAI17571.1.
AL935032 Genomic DNA. Translation: CAI18476.1.
BX120007 Genomic DNA. Translation: CAM26203.1.
Z84814 Genomic DNA. Translation: CAB06609.1.
CH471081 Genomic DNA. Translation: EAX03630.1.
BC032350 mRNA. Translation: AAH32350.1.
BC071659 mRNA. Translation: AAH71659.1.
V00523 mRNA. Translation: CAA23782.1.
J00201 Genomic DNA. Translation: AAA36301.1.
AF481359 Genomic DNA. Translation: AAO23887.1.
CCDSiCCDS4750.1.
PIRiA93952. HLHUDA.
RefSeqiNP_061984.2. NM_019111.4.
UniGeneiHs.520048.

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
EntryMethodResolution (Å)ChainPositionsPDBsum
1A6AX-ray2.75A30-205[»]
1AQDX-ray2.45A/D/G/J26-217[»]
1BX2X-ray2.60A/D27-206[»]
1D5MX-ray2.00A26-206[»]
1D5XX-ray2.45A26-206[»]
1D5ZX-ray2.00A26-206[»]
1D6EX-ray2.45A26-206[»]
1DLHX-ray2.80A/D28-207[»]
1FV1X-ray1.90A/D26-206[»]
1FYTX-ray2.60A26-206[»]
1H15X-ray3.10A/D26-207[»]
1HQRX-ray3.20A26-206[»]
1HXYX-ray2.60A26-207[»]
1J8HX-ray2.40A26-206[»]
1JWMX-ray2.70A26-207[»]
1JWSX-ray2.60A26-207[»]
1JWUX-ray2.30A26-207[»]
1KG0X-ray2.65A28-207[»]
1KLGX-ray2.40A29-205[»]
1KLUX-ray1.93A29-207[»]
1LO5X-ray3.20A26-207[»]
1PYWX-ray2.10A26-207[»]
1R5IX-ray2.60A/E26-206[»]
1SEBX-ray2.70A/E26-206[»]
1SJEX-ray2.45A28-207[»]
1SJHX-ray2.25A28-207[»]
1T5WX-ray2.40A/D27-206[»]
1T5XX-ray2.50A27-207[»]
1YMMX-ray3.50A26-216[»]
1ZGLX-ray2.80A/D/G/J26-206[»]
2FSEX-ray3.10A/C29-205[»]
2G9HX-ray2.00A26-207[»]
2IAMX-ray2.80A26-207[»]
2IANX-ray2.80A/F/K/P26-207[»]
2ICWX-ray2.41A/D28-206[»]
2IPKX-ray2.30A26-207[»]
2OJEX-ray3.00A/E27-206[»]
2Q6WX-ray2.25A/D26-207[»]
2SEBX-ray2.50A26-206[»]
2WBJX-ray3.00A/E26-218[»]
2XN9X-ray2.30D26-207[»]
3C5JX-ray1.80A26-206[»]
3L6FX-ray2.10A26-207[»]
3O6FX-ray2.80A/E26-207[»]
3PDOX-ray1.95A26-217[»]
3PGCX-ray2.66A/D26-217[»]
3PGDX-ray2.72A/D26-217[»]
3QXAX-ray2.71A/D26-207[»]
3QXDX-ray2.30A/D26-207[»]
3S4SX-ray2.40A/D26-207[»]
3S5LX-ray2.10A/D26-207[»]
3T0EX-ray4.00A26-207[»]
4AENX-ray2.20A26-217[»]
4AH2X-ray2.36A26-217[»]
4C56X-ray2.90D/J26-207[»]
4E41X-ray2.60A/F26-207[»]
4FQXX-ray2.60A26-216[»]
4GBXX-ray3.00A26-216[»]
4H1LX-ray3.30A/D28-205[»]
4H25X-ray2.20A/D28-207[»]
4H26X-ray2.50A/D28-206[»]
4I5BX-ray2.12A/D27-213[»]
4IS6X-ray2.50A26-207[»]
4MCYX-ray2.30A26-206[»]
4MCZX-ray2.41A26-206[»]
4MD0X-ray2.19A26-206[»]
4MD4X-ray1.95A26-206[»]
4MD5X-ray1.65A26-206[»]
4MDIX-ray2.00A26-206[»]
4MDJX-ray1.70A26-206[»]
4OV5X-ray2.20A/D/G/J/M/P26-207[»]
ProteinModelPortaliP01903.
SMRiP01903. Positions 28-206.
ModBaseiSearch...
MobiDBiSearch...

Protein-protein interaction databases

BioGridi109367. 39 interactions.
DIPiDIP-6063N.
IntActiP01903. 10 interactions.
MINTiMINT-203259.

Protein family/group databases

Allergomei8362. Hom s HLA-DR-alpha.

PTM databases

PhosphoSiteiP01903.

Polymorphism and mutation databases

BioMutaiHLA-DRA.
DMDMi122206.

Proteomic databases

MaxQBiP01903.
PaxDbiP01903.
PRIDEiP01903.

Protocols and materials databases

DNASUi3122.
Structural Biology KnowledgebaseSearch...

Genome annotation databases

EnsembliENST00000383127; ENSP00000372608; ENSG00000227993.
ENST00000383259; ENSP00000372746; ENSG00000206308.
ENST00000395388; ENSP00000378786; ENSG00000204287.
ENST00000411524; ENSP00000405295; ENSG00000234794.
ENST00000414698; ENSP00000402951; ENSG00000230726.
ENST00000416883; ENSP00000410443; ENSG00000228987.
ENST00000442960; ENSP00000404533; ENSG00000226260.
GeneIDi3122.
KEGGihsa:3122.
UCSCiuc003obh.3. human.

Organism-specific databases

CTDi3122.
GeneCardsiGC06P032412.
GC06Pj32355.
GC06Pk32382.
GC06Pl32446.
GC06Pm32482.
GC06Pn32365.
GC06Po32413.
H-InvDBHIX0005752.
HIX0031098.
HIX0166957.
HIX0167205.
HIX0167443.
HGNCiHGNC:4947. HLA-DRA.
HPAiCAB002798.
CAB015402.
HPA050162.
HPA053176.
MIMi142860. gene.
610424. phenotype.
neXtProtiNX_P01903.
Orphaneti505. Graham Little-Piccardi-Lassueur syndrome.
PharmGKBiPA35071.
GenAtlasiSearch...

Phylogenomic databases

eggNOGiNOG44736.
HOVERGENiHBG006862.
InParanoidiP01903.
KOiK06752.
OMAiMIKRSNH.
PhylomeDBiP01903.
TreeFamiTF333797.

Enzyme and pathway databases

ReactomeiREACT_121399. MHC class II antigen presentation.
REACT_12555. Downstream TCR signaling.
REACT_12582. Phosphorylation of CD3 and TCR zeta chains.
REACT_12596. Translocation of ZAP-70 to Immunological synapse.
REACT_12623. Generation of second messenger molecules.
REACT_19324. PD-1 signaling.
REACT_25078. Interferon gamma signaling.

Miscellaneous databases

ChiTaRSiHLA-DRA. human.
EvolutionaryTraceiP01903.
GeneWikiiHLA-DRA.
GenomeRNAii3122.
NextBioi12390.
PROiP01903.
SOURCEiSearch...

Gene expression databases

BgeeiP01903.
CleanExiHS_HLA-DRA.
ExpressionAtlasiP01903. baseline and differential.
GenevisibleiP01903. HS.

Family and domain databases

Gene3Di2.60.40.10. 1 hit.
3.10.320.10. 1 hit.
InterProiIPR007110. Ig-like_dom.
IPR013783. Ig-like_fold.
IPR003006. Ig/MHC_CS.
IPR003597. Ig_C1-set.
IPR011162. MHC_I/II-like_Ag-recog.
IPR014745. MHC_II_a/b_N.
IPR001003. MHC_II_a_N.
[Graphical view]
PfamiPF07654. C1-set. 1 hit.
PF00993. MHC_II_alpha. 1 hit.
[Graphical view]
SMARTiSM00407. IGc1. 1 hit.
SM00920. MHC_II_alpha. 1 hit.
[Graphical view]
SUPFAMiSSF54452. SSF54452. 1 hit.
PROSITEiPS50835. IG_LIKE. 1 hit.
PS00290. IG_MHC. 1 hit.
[Graphical view]
ProtoNetiSearch...

Publicationsi

« Hide 'large scale' publications
  1. "Sequence of an HLA-DR alpha-chain cDNA clone and intron-exon organization of the corresponding gene."
    Lee J.S., Trowsdale J., Travers P.J., Carey J., Grosveld F., Jenkins J., Bodmer W.F.
    Nature 299:750-752(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE DRA*01:01).
  2. "Cloning the heavy chain of human HLA-DR antigen using synthetic oligodeoxyribonucleotides as hybridization probes."
    Kajimura Y., Toyoda H., Sato M., Miyakoshi S., Kaplan S.A., Ike Y., Goyert S.M., Silver J., Hawke D., Shively J.E., Suggs S.V., Wallace R.B., Itakura K.
    DNA 2:175-182(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE DRA*01:01).
  3. "Organization of the transcriptional unit of a human class II histocompatibility antigen: HLA-DR heavy chain."
    Schamboeck A., Korman A.J., Kamb A., Strominger J.L.
    Nucleic Acids Res. 11:8663-8675(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELE DRA*01:02).
  4. "Structure and nucleotide sequence of the heavy chain gene of HLA-DR."
    Das H.K., Lawrance S.K., Weissman S.M.
    Proc. Natl. Acad. Sci. U.S.A. 80:3543-3547(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELE DRA*01:01).
  5. Erratum
    Das H.K., Lawrance S.K., Weissman S.M.
    Proc. Natl. Acad. Sci. U.S.A. 80:7024-7024(1983)
    Cited for: SEQUENCE REVISION.
  6. "Rapid nonlysosomal degradation of assembled HLA class II glycoproteins incorporating a mutant DR alpha-chain."
    Koppelman B., Cresswell P.
    J. Immunol. 145:2730-2736(1990) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE DRA*01:02).
  7. "Cloning of human full open reading frames in Gateway(TM) system entry vector (pDONR201)."
    Ebert L., Schick M., Neubert P., Schatten R., Henze S., Korn B.
    Submitted (JUN-2004) to the EMBL/GenBank/DDBJ databases
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] (ALLELE DRA*01:01).
  8. "The DNA sequence and analysis of human chromosome 6."
    Mungall A.J., Palmer S.A., Sims S.K., Edwards C.A., Ashurst J.L., Wilming L., Jones M.C., Horton R., Hunt S.E., Scott C.E., Gilbert J.G.R., Clamp M.E., Bethel G., Milne S., Ainscough R., Almeida J.P., Ambrose K.D., Andrews T.D.
    , Ashwell R.I.S., Babbage A.K., Bagguley C.L., Bailey J., Banerjee R., Barker D.J., Barlow K.F., Bates K., Beare D.M., Beasley H., Beasley O., Bird C.P., Blakey S.E., Bray-Allen S., Brook J., Brown A.J., Brown J.Y., Burford D.C., Burrill W., Burton J., Carder C., Carter N.P., Chapman J.C., Clark S.Y., Clark G., Clee C.M., Clegg S., Cobley V., Collier R.E., Collins J.E., Colman L.K., Corby N.R., Coville G.J., Culley K.M., Dhami P., Davies J., Dunn M., Earthrowl M.E., Ellington A.E., Evans K.A., Faulkner L., Francis M.D., Frankish A., Frankland J., French L., Garner P., Garnett J., Ghori M.J., Gilby L.M., Gillson C.J., Glithero R.J., Grafham D.V., Grant M., Gribble S., Griffiths C., Griffiths M.N.D., Hall R., Halls K.S., Hammond S., Harley J.L., Hart E.A., Heath P.D., Heathcott R., Holmes S.J., Howden P.J., Howe K.L., Howell G.R., Huckle E., Humphray S.J., Humphries M.D., Hunt A.R., Johnson C.M., Joy A.A., Kay M., Keenan S.J., Kimberley A.M., King A., Laird G.K., Langford C., Lawlor S., Leongamornlert D.A., Leversha M., Lloyd C.R., Lloyd D.M., Loveland J.E., Lovell J., Martin S., Mashreghi-Mohammadi M., Maslen G.L., Matthews L., McCann O.T., McLaren S.J., McLay K., McMurray A., Moore M.J.F., Mullikin J.C., Niblett D., Nickerson T., Novik K.L., Oliver K., Overton-Larty E.K., Parker A., Patel R., Pearce A.V., Peck A.I., Phillimore B.J.C.T., Phillips S., Plumb R.W., Porter K.M., Ramsey Y., Ranby S.A., Rice C.M., Ross M.T., Searle S.M., Sehra H.K., Sheridan E., Skuce C.D., Smith S., Smith M., Spraggon L., Squares S.L., Steward C.A., Sycamore N., Tamlyn-Hall G., Tester J., Theaker A.J., Thomas D.W., Thorpe A., Tracey A., Tromans A., Tubby B., Wall M., Wallis J.M., West A.P., White S.S., Whitehead S.L., Whittaker H., Wild A., Willey D.J., Wilmer T.E., Wood J.M., Wray P.W., Wyatt J.C., Young L., Younger R.M., Bentley D.R., Coulson A., Durbin R.M., Hubbard T., Sulston J.E., Dunham I., Rogers J., Beck S.
    Nature 425:805-811(2003) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA] (ALLELES DRA*01:01 AND DRA*01:02).
  9. Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA] (ALLELE DRA*01:01).
  10. "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] (ALLELES DRA*01:01 AND DRA*01:02).
    Tissue: Blood and Colon.
  11. "Primary structure of class II human histocompatibility antigens. 2nd Communication. Amino acid sequence of the N-terminal 179 residues of the alpha-chain of an HLA-Dw2/DR2 alloantigen."
    Yang C.-Y., Kratzin H., Gotz H., Thinnes F.P., Kruse T., Egert G., Pauly E., Kolbel S., Wernet P., Hilschmann N.
    Hoppe-Seyler's Z. Physiol. Chem. 363:671-676(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 26-204.
  12. "N-terminal amino acid sequences of the alpha and beta chains of HLA-DR1 and HLA-DR2 antigens."
    Walker L.E., Hewick R., Hunkapiller M.W., Hood L.E., Dreyer W.J., Reisfeld R.A.
    Biochemistry 22:185-188(1983) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 26-94.
    Tissue: B-cell.
  13. "Alpha chain of HLA-DR transplantation antigens is a member of the same protein superfamily as the immunoglobulins."
    Larhammar D., Gustafsson K., Claesson L., Bill P., Wiman K., Schenning L., Sundelin J., Widmark E., Peterson P.A., Rask L.
    Cell 30:153-161(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: PROTEIN SEQUENCE OF 26-60, NUCLEOTIDE SEQUENCE [MRNA] OF 32-202 AND 204-254.
  14. "The amino acid sequence and gene organization of the heavy chain of the HLA-DR antigen: homology to immunoglobulins."
    Korman A.J., Auffray C., Schamboeck A., Strominger J.L.
    Proc. Natl. Acad. Sci. U.S.A. 79:6013-6017(1982) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 29-254 (ALLELE DRA*01:02).
  15. "The HLA-DRA*0102 allele: correct nucleotide sequence and associated HLA haplotypes."
    Kralovicova J., Marsh S.G., Waller M.J., Hammarstrom L., Vorechovsky I.
    Tissue Antigens 60:266-267(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 205-254 (ALLELE DRA*01:02).
    Tissue: Blood.
  16. "Heterozygote advantage for HLA class-II type in hepatitis B virus infection."
    Thursz M.R., Thomas H.C., Greenwood B.M., Hill A.V.S.
    Nat. Genet. 17:11-12(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: INVOLVEMENT IN SUSCEPTIBILITY TO HBV INFECTION.
  17. Erratum
    Thursz M.R., Thomas H.C., Greenwood B.M., Hill A.V.S.
    Nat. Genet. 18:88-88(1998)
  18. "Invariant chain structure and MHC class II function."
    Cresswell P.
    Cell 84:505-507(1996) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  19. "Presentation of antigens by MHC class II molecules: getting the most out of them."
    Villadangos J.A.
    Mol. Immunol. 38:329-346(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  20. "MHC class II molecules on the move for successful antigen presentation."
    Rocha N., Neefjes J.
    EMBO J. 27:1-5(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  21. "Autophagy in MHC class II presentation: sampling from within."
    Menendez-Benito V., Neefjes J.
    Immunity 26:1-3(2007) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  22. "MHC class II stabilization at the surface of human dendritic cells is the result of maturation-dependent MARCH I down-regulation."
    De Gassart A., Camosseto V., Thibodeau J., Ceppi M., Catalan N., Pierre P., Gatti E.
    Proc. Natl. Acad. Sci. U.S.A. 105:3491-3496(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: SUBCELLULAR LOCATION.
  23. "MHC class II transport at a glance."
    Berger A.C., Roche P.A.
    J. Cell Sci. 122:1-4(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  24. "CD74 in antigen presentation, inflammation, and cancers of the gastrointestinal tract."
    Beswick E.J., Reyes V.E.
    World J. Gastroenterol. 15:2855-2861(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: REVIEW.
  25. "The HLA-DRalpha chain is modified by polyubiquitination."
    Lapaque N., Jahnke M., Trowsdale J., Kelly A.P.
    J. Biol. Chem. 284:7007-7016(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: UBIQUITINATION AT LYS-244 BY MARCH1 AND MARCH8, MUTAGENESIS OF LYS-244, SUBCELLULAR LOCATION.
  26. "Glycoproteomics analysis of human liver tissue by combination of multiple enzyme digestion and hydrazide chemistry."
    Chen R., Jiang X., Sun D., Han G., Wang F., Ye M., Wang L., Zou H.
    J. Proteome Res. 8:651-661(2009) [PubMed] [Europe PMC] [Abstract]
    Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-103 AND ASN-143.
    Tissue: Liver.
  27. Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
  28. "An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
    Bian Y., Song C., Cheng K., Dong M., Wang F., Huang J., Sun D., Wang L., Ye M., Zou H.
    J. Proteomics 96:253-262(2014) [PubMed] [Europe PMC] [Abstract]
    Cited for: IDENTIFICATION BY MASS SPECTROMETRY [LARGE SCALE ANALYSIS].
    Tissue: Liver.
  29. "Three-dimensional structure of the human class II histocompatibility antigen HLA-DR1."
    Brown J.H., Jardetzky T.S., Gorga J.C., Stern L.J., Urban R.G., Strominger J.L., Wiley D.C.
    Nature 364:33-39(1993) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF 28-207.
  30. "Crystal structure of the human class II MHC protein HLA-DR1 complexed with an influenza virus peptide."
    Stern L.J., Brown J.H., Jardetzky T.J., Gorga J.C., Urban R.G., Strominger J.L., Wiley D.C.
    Nature 368:215-221(1994) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF 28-207.
  31. "Three-dimensional structure of a human class II histocompatibility molecule complexed with superantigen."
    Jardetzky T.S., Brown J.H., Gorga J.C., Stern L.J., Urban R.G., Chi Y.I., Stauffacher C., Strominger J.L., Wiley D.C.
    Nature 368:711-718(1994) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.7 ANGSTROMS) OF COMPLEX WITH SEB.
  32. "The structure of an intermediate in class II MHC maturation: CLIP bound to HLA-DR3."
    Ghosh P., Amaya M., Mellins E., Wiley D.C.
    Nature 378:457-462(1995) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.75 ANGSTROMS) OF 30-205 OF HLA-DRA/HLA-DRB1 HETERODIMER IN COMPLEX WITH CD74 PEPTIDE (CLIP), SUBUNIT, GLYCOSYLATION AT ASN-103 AND ASN-143, DISULFIDE BOND.
  33. "X-ray crystal structure of HLA-DR4 (DRA*0101, DRB1*0401) complexed with a peptide from human collagen II."
    Dessen A., Lawrence C.M., Cupo S., Zaller D.M., Wiley D.C.
    Immunity 7:473-481(1997) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.5 ANGSTROMS) OF COMPLEX WITH PEPTIDE FROM COLLAGEN.
  34. "Crystal structure of HLA-DR2 (DRA*0101, DRB1*1501) complexed with a peptide from human myelin basic protein."
    Smith K.J., Pyrdol J., Gauthier L., Wiley D.C., Wucherpfennig K.W.
    J. Exp. Med. 188:1511-1520(1998) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.6 ANGSTROMS) OF COMPLEX WITH PEPTIDE FROM MYELIN BASIC PROTEIN.
  35. "Structural basis for the binding of an immunodominant peptide from myelin basic protein in different registers by two HLA-DR2 proteins."
    Li Y., Li H., Martin R., Mariuzza R.A.
    J. Mol. Biol. 304:177-188(2000) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) OF 26-206 OF HLA-DRA/HLA-DRB5 HETERODIMER IN COMPLEX WITH MBP PEPTIDE, SUBUNIT.
  36. "Crystal structure of a superantigen bound to the high-affinity, zinc-dependent site on MHC class II."
    Li Y., Li H., Dimasi N., McCormick J.K., Martin R., Schuck P., Schlievert P.M., Mariuzza R.A.
    Immunity 14:93-104(2001) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (3.2 ANGSTROMS) OF 26-206 OF HLA-DRA/HLA-DRB5 HETERODIMER IN COMPLEX WITH MBP PEPTIDE AND STREPTOCOCCUS PYOGENES SPEC PEPTIDE, SUBUNIT, DISULFIDE BOND.
  37. "Structure of the Epstein-Barr virus gp42 protein bound to the MHC class II receptor HLA-DR1."
    Mullen M.M., Haan K.M., Longnecker R., Jardetzky T.S.
    Mol. Cell 9:375-385(2002) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.65 ANGSTROMS) OF 28-207 IN COMPLEX WITH EPSTEIN-BARR VIRUS BZLF2/GP42.
  38. Cited for: X-RAY CRYSTALLOGRAPHY (3.1 ANGSTROMS) OF 26-207 OF HLA-DRA/HLA-DRB5 HETERODIMER IN COMPLEX EPSTEIN-BARR VIRUS BALF5 PEPTIDE, SUBUNIT, DISULFIDE BOND.
  39. "Structure of a human autoimmune TCR bound to a myelin basic protein self-peptide and a multiple sclerosis-associated MHC class II molecule."
    Li Y., Huang Y., Lue J., Quandt J.A., Martin R., Mariuzza R.A.
    EMBO J. 24:2968-2979(2005) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.8 ANGSTROMS) OF 26-206 OF HLA-DRA/HLA-DRB5 HETERODIMER IN COMPLEX WITH MBP PEPTIDE AND TRAC, SUBUNIT, DISULFIDE BOND.
  40. "Crystallographic structure of the human leukocyte antigen DRA, DRB3*0101: models of a directional alloimmune response and autoimmunity."
    Parry C.S., Gorski J., Stern L.J.
    J. Mol. Biol. 371:435-446(2007) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (2.25 ANGSTROMS) OF 26-207 OF HLA-DRA/HLA-DRB3 HETERODIMER IN COMPLEX WITH ITGB3 PEPTIDE (ALLOANTIGEN HPA-1A), SUBUNIT, DISULFIDE BOND.
  41. "The structure of HLA-DR52c: comparison to other HLA-DRB3 alleles."
    Dai S., Crawford F., Marrack P., Kappler J.W.
    Proc. Natl. Acad. Sci. U.S.A. 105:11893-11897(2008) [PubMed] [Europe PMC] [Abstract]
    Cited for: X-RAY CRYSTALLOGRAPHY (1.8 ANGSTROMS) OF 26-206 OF HLA-DRA/HLA-DRB3 HETERODIMER IN COMPLEX WITH EEF1A2 PEPTIDE.

Entry informationi

Entry nameiDRA_HUMAN
AccessioniPrimary (citable) accession number: P01903
Secondary accession number(s): A2BET4
, Q30160, Q6IAZ1, Q861I2, Q9TP70
Entry historyi
Integrated into UniProtKB/Swiss-Prot: July 21, 1986
Last sequence update: July 21, 1986
Last modified: June 24, 2015
This is version 164 of the entry and version 1 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

3D-structure, Complete proteome, Direct protein sequencing, Reference proteome

Documents

  1. Human chromosome 6
    Human chromosome 6: 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. PDB cross-references
    Index of Protein Data Bank (PDB) cross-references
  6. 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.