Reviewed, UniProtKB/Swiss-Prot P03989 (1B27_HUMAN)

Names and origin

Protein names

Recommended name:
    HLA class I histocompatibility antigen, B-27 alpha chain
Alternative name(s):
    MHC class I antigen B*27

Gene names

Name:	HLA-B
Synonyms:	HLAB

Organism

Homo sapiens (Human) [Complete proteome]

Taxonomic identifier

9606 [NCBI]

Taxonomic lineage

Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi › Mammalia › Eutheria › Euarchontoglires › Primates › Haplorrhini › Catarrhini › Hominidae › Homo

Protein attributes

Sequence length	362 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is further processed into a mature form.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Involved in the presentation of foreign antigens to the immune system.
Subunit structure	Heterodimer of an alpha chain and a beta chain (beta-2-microglobulin). Interacts with human herpesvirus 8 MIR1 protein By similarity.
Subcellular location	Membrane; Single-pass type I membrane protein.
Post-translational modification	Polyubiquitinated in a post ER compartment by interaction with human herpesvirus 8 MIR1 protein. This targets the protein for rapid degradation via the ubiquitin system By similarity.
Polymorphism	The following alleles of B-27 are known: B*2701=B*2705, B*2702 (B27.2; B-27k; B27e), B*2703 (B27d), B*2704, B*2706, B*2707, B*2708 (B7Qui) and B*2709 (B27-ci). The sequence shown is that of B*2701.
Involvement in disease	HLA-B27 is associated with the development of ankylosing spondylitis (AS) [MIM:106300]. AS is a chronic inflammatory rheumatic disease that mainly affects the axial skeleton and is considered the prototype of seronegative spondyloarthropathies (SNSA), which include reactive arthritis (e.g., Reiter's syndrome), psoritic spondylitis, and other spondyloarthropathies (SpA). In the Greek Cypriot population, a restricted number of HLA-B27 subtypes are associated with AS and other B27-related diseases and an elevated frequency of the B*2702 allele in the AS patients is identified. The allele B*2707 seems to have a protective role in this population because it was found only in the healthy controls. Ref.19
Sequence similarities	Belongs to the MHC class I family. Contains 1 Ig-like C1-type (immunoglobulin-like) domain.

Ontologies

Keywords
Biological process	Host-virus interaction Immune response
Cellular component	MHC I Membrane
Coding sequence diversity	Polymorphism
Domain	Signal Transmembrane
PTM	Disulfide bond Glycoprotein Ubl conjugation
Technical term	3D-structure Complete proteome Direct protein sequencing
Gene Ontology (GO)
Biological process	antigen processing and presentation of peptide antigen via MHC class I Inferred from electronic annotation. Source: UniProtKB-KW defense response Ref.4 Traceable author statement. Source: UniProtKB immune response Inferred from electronic annotation. Source: UniProtKB-KW interspecies interaction between organisms Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	MHC class I protein complex Inferred from electronic annotation. Source: UniProtKB-KW integral to membrane Inferred from electronic annotation. Source: UniProtKB-KW membrane fraction Ref.4 Traceable author statement. Source: UniProtKB
Complete GO annotation...

Sequence annotation (Features)

Feature key

Position(s)

Length

Description

Graphical view

Feature identifier

Molecule processing

Signal peptide

1 – 24

24

Ref.3

Chain

25 – 362

338

HLA class I histocompatibility antigen, B-27 alpha chain

PRO_0000018839

Regions

Topological domain

25 – 308

284

Extracellular Potential

Transmembrane

309 – 332

24

Potential

Topological domain

333 – 362

30

Cytoplasmic Potential

Domain

209 – 295

87

Ig-like C1-type

Region

25 – 114

90

Alpha-1

Region

115 – 206

92

Alpha-2

Region

207 – 298

92

Alpha-3

Region

299 – 308

10

Connecting peptide

Amino acid modifications

Glycosylation

110

1

N-linked (GlcNAc...)

Disulfide bond

125 ↔ 188

Disulfide bond

227 ↔ 283

Natural variations

Natural variant

65

1

A → T: dbSNP rs1050529.

VAR_056341

Natural variant

83

1

Y → H in allele B*2703.

VAR_016379

Natural variant

101

1

D → N in allele B*2702.

VAR_016380

Natural variant

101

1

D → S in allele B*2704, allele B*2706 and allele B*2708; requires 2 nucleotide substitutions.

VAR_016381

Natural variant

104 – 105

2

TL → IA in allele B*2702.

VAR_016382

Natural variant

104

1

T → N in allele B*2708.

VAR_016383

Natural variant

106 – 107

2

LR → RG in allele B*2708.

VAR_016384

Natural variant

121

1

N → S in allele B*2707.

VAR_016385

Natural variant

137 – 138

2

YH → HN in allele B*2707.

VAR_016386

Natural variant

138

1

H → D in allele B*2706.

VAR_016387

Natural variant

140

1

D → H in allele B*2709.

VAR_016388

Natural variant

140

1

D → Y in allele B*2706 and allele B*2707.

VAR_016389

Natural variant

155

1

S → R in allele B*2707.

VAR_016390

Natural variant

176

1

V → E in allele B*2704 and allele B*2706.

VAR_016391

Natural variant

235

1

A → G in allele B*2704 and allele B*2706.

VAR_016392

Natural variant

306

1

V → I: dbSNP rs1131500.

VAR_056342

Natural variant

329

1

A → T: dbSNP rs1051488.

VAR_056343

Experimental info

Sequence conflict

206

1

A → V Ref.2

Sequence conflict

266

1

Q → E AA sequence Ref.3

Secondary structure

1

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362

Helix Strand Turn

Details...

Beta strand

27 – 36

10

Beta strand

41 – 43

3

Beta strand

45 – 52

8

Beta strand

55 – 61

7

Beta strand

64 – 66

3

Helix

74 – 76

3

Helix

81 – 108

28

Beta strand

113 – 115

3

Beta strand

118 – 127

10

Beta strand

133 – 142

10

Beta strand

145 – 150

6

Beta strand

157 – 161

5

Helix

162 – 173

12

Helix

176 – 185

10

Helix

187 – 198

12

Turn

199 – 204

6

Beta strand

210 – 219

10

Beta strand

222 – 235

14

Beta strand

238 – 243

6

Helix

249 – 251

3

Beta strand

261 – 263

3

Beta strand

265 – 274

10

Helix

278 – 280

3

Beta strand

281 – 286

6

Beta strand

294 – 296

3

Sequences

	Sequence		Length	Mass (Da)
	P03989-1 [UniParc]. Last modified August 13, 1987. Version 2. Checksum: C8D2F154E3292031	FASTA	362	40,428
	10 20 30 40 50 60 MRVTAPRTLL LLLWGAVALT ETWAGSHSMR YFHTSVSRPG RGEPRFITVG YVDDTLFVRF 70 80 90 100 110 120 DSDAASPREE PRAPWIEQEG PEYWDRETQI CKAKAQTDRE DLRTLLRYYN QSEAGSHTLQ 130 140 150 160 170 180 NMYGCDVGPD GRLLRGYHQD AYDGKDYIAL NEDLSSWTAA DTAAQITQRK WEAARVAEQL 190 200 210 220 230 240 RAYLEGECVE WLRRYLENGK ETLQRADPPK THVTHHPISD HEATLRCWAL GFYPAEITLT 250 260 270 280 290 300 WQRDGEDQTQ DTELVETRPA GDRTFQKWAA VVVPSGEEQR YTCHVQHEGL PKPLTLRWEP 310 320 330 340 350 360 SSQSTVPIVG IVAGLAVLAV VVIGAVVAAV MCRRKSSGGK GGSYSQAACS DSAQGSDVSL TA

References

	« Hide 'large scale' referencesShow 'large scale' references »
[1]	"Organization, sequence and expression of the HLA-B27 gene: a molecular approach to analyze HLA and disease associations." Weiss E.H., Kuon W., Doerner C., Lang M., Riethmueller G. Immunobiology 170:367-380(1985) [PubMed: 3912316] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELE B*2701).
[2]	"Complete sequence of HLA-B27 cDNA identified through the characterization of structural markers unique to the HLA-A, -B, and -C allelic series." Szoets H., Riethmueller G., Weiss E., Meo T. Proc. Natl. Acad. Sci. U.S.A. 83:1428-1432(1986) [PubMed: 3485286] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] OF 25-361 (ALLELE B*2701).
[3]	"Primary structure of papain-solubilized human histocompatibility antigen HLA-B27." Ezquerra A., Bragado R., Vega M.A., Strominger J.L., Woody J., Lopez de Castro J.A. Biochemistry 24:1733-1741(1985) [PubMed: 2408663] [Abstract] Cited for: PROTEIN SEQUENCE OF 25-295 (B*2701).
[4]	"Gene conversion-like mechanisms may generate polymorphism in human class I genes." Seemann G.H.A., Rein R.S., Brown C.S., Ploegh H.L. EMBO J. 5:547-552(1986) [PubMed: 3011411] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELES B*2701 AND B*2702).
[5]	"On the nucleotide sequences of B*2702 and B*2705." Moses J.H., Marsh S.G.E., Arnett K.L., Adams E.J., Bodmer J.G., Parham P. Tissue Antigens 46:50-53(1995) [PubMed: 7482496] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE B*2702).
[6]	"Structural analysis of an HLA-B27 functional variant: identification of residues that contribute to the specificity of recognition by cytolytic T lymphocytes." Vega M.A., Ezquerra A., Rojo S., Aparicio P., Bragado R., Lopez de Castro J.A. Proc. Natl. Acad. Sci. U.S.A. 82:7394-7398(1985) [PubMed: 2414775] [Abstract] Cited for: PROTEIN SEQUENCE OF 86-107 AND 171-181 (B*2702).
[7]	"Molecular analysis of the variant alloantigen HLA-B27d (HLA-B*2703) identifies a unique single amino acid substitution." Choo S.Y., St John T., Orr H.T., Hansen J.A. Hum. Immunol. 21:209-219(1988) [PubMed: 3286582] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] (ALLELE B*2703).
[8]	"The nucleotide sequence of HLA-B*2704 reveals a new amino acid substitution in exon 4 which is also present in HLA-B*2706." Rudwaleit M., Bowness P., Wordsworth P. Immunogenetics 43:160-162(1996) [PubMed: 8550101] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELES B*2704 AND B*2706).
[9]	"Absence of polymorphism between HLA-B27 genomic exon sequences isolated from normal donors and ankylosing spondylitis patients." Coppin H.L., McDevitt H.O. J. Immunol. 137:2168-2172(1986) [PubMed: 3489755] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [GENOMIC DNA] OF 25-298 (ALLELE B*2705).
[10]	"Nucleotide sequence of HLA-B*2706." Vilches C., de Pablo R., Kreisler M. Immunogenetics 39:219-219(1994) [PubMed: 8276469] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE B*2706).
[11]	"A novel HLA-B27 allele maps B27 allospecificity to the region around position 70 in the alpha 1 domain." Choo Y.S., Fan L.A., Hansen J.A. J. Immunol. 147:174-180(1991) [PubMed: 1711072] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE B*2707).
[12]	"The HLA-B7Qui antigen is encoded by a new subtype of HLA-B27 (B*2708)." Hildebrand W.H., Domena J.D., Shen S.Y., Marsh S.G.E., Bunce M., Guttridge M.G., Darke C., Parham P. Tissue Antigens 44:47-51(1994) [PubMed: 7974468] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE B*2708).
[13]	"Identification of a novel HLA-B27 subtype by restriction analysis of a cytotoxic gamma/delta T cell clone." Del Porto P., D'Amato M., Fiorillo M.T., Tuosto L., Piccolella E., Sorrentino R. J. Immunol. 153:3093-3100(1994) [PubMed: 8089488] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA] (ALLELE B*2709). Tissue: Blood.
[14]	"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: 19159218] [Abstract] Cited for: GLYCOSYLATION [LARGE SCALE ANALYSIS] AT ASN-110, MASS SPECTROMETRY. Tissue: Liver.
[15]	"The three-dimensional structure of HLA-B27 at 2.1-A resolution suggests a general mechanism for tight peptide binding to MHC." Madden D.R., Gorga J.C., Strominger J.L., Wiley D.C. Cell 70:1035-1048(1992) [PubMed: 1525820] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.1 ANGSTROMS) OF 25-300.
[16]	"The structure of HLA-B27 reveals nonamer self-peptides bound in an extended conformation." Madden D.R., Gorga J.C., Strominger J.L., Wiley D.C. Nature 353:321-325(1991) [PubMed: 1922337] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (1.9 ANGSTROMS) OF 25-300.
[17]	"HLA-B27 subtypes differentially associated with disease exhibit subtle structural alterations." Hulsmeyer M., Hillig R.C., Volz A., Ruhl M., Schroder W., Saenger W., Ziegler A., Uchanska-Ziegler B. J. Biol. Chem. 277:47844-47853(2002) [PubMed: 12244049] [Abstract] Cited for: X-RAY CRYSTALLOGRAPHY (2.1 ANGSTROMS) OF 25-300.
[18]	"Rational design of nonnatural peptides as high-affinity ligands for the HLA-B*2705 human leukocyte antigen." Rognan D., Scapozza L., Folkers G., Daser A. Proc. Natl. Acad. Sci. U.S.A. 92:753-757(1995) [PubMed: 7846047] [Abstract] Cited for: 3D-STRUCTURE MODELING OF 115-206.
[19]	"HLA-B27 in the Greek Cypriot population: distribution of subtypes in patients with ankylosing spondylitis and other HLA-B27-related diseases. The possible protective role of B*2707." Varnavidou-Nicolaidou A., Karpasitou K., Georgiou D., Stylianou G., Kokkofitou A., Michalis C., Constantina C., Gregoriadou C., Kyriakides G. Hum. Immunol. 65:1451-1454(2004) [PubMed: 15603872] [Abstract] Cited for: DISEASE, POSSIBLE PROTECTIVE ROLE OF ALLELE B*2707.
+	Additional computationally mapped references.

Cross-references

Sequence databases

EMBLGenBankDDBJ

X03945 Genomic DNA. Translation: CAA27578.1. Sequence problems.
X03664, X03667 Genomic DNA. Translation: CAA27301.1.
L38504 mRNA. Translation: AAA69724.1.
M54883 Genomic DNA. Translation: AAA59616.1.
X03665, X03666 Genomic DNA. Translation: CAA27302.1.
M12967 Genomic DNA. Translation: AAA36221.1.
U27608 mRNA. Translation: AAC50444.1.
U35734 mRNA. Translation: AAC50447.1.
M14013 Genomic DNA. Translation: AAA59643.1.
X73578 mRNA. Translation: CAA51980.1.
M62852 mRNA. Translation: AAA59647.1.
L19923 mRNA. Translation: AAA59658.1.
Z33453 mRNA. Translation: CAA83876.1.

IPI

IPI00471986.

PIR

I37515.
I56116.
HLHUB2. S07441.

UniGene

Hs.703277
Hs.707171
Hs.77961

3D structure databases

PDBPDBe

Entry	Method	Resolution (Å)	Chain	Positions	PDBsum
1HSA	X-ray	2.10	A/D	25-300	[»]
1JGD	X-ray	1.90	A	25-300	[»]
1JGE	X-ray	2.10	A	25-300	[»]
1K5N	X-ray	1.09	A	25-300	[»]
1OF2	X-ray	2.20	A	25-300	[»]
1OGT	X-ray	1.47	A	25-300	[»]
1ROG	model	-	A	25-206	[»]
1ROH	model	-	A	25-206	[»]
1ROI	model	-	A	25-206	[»]
1ROJ	model	-	A	25-206	[»]
1ROK	model	-	A	25-206	[»]
1ROL	model	-	A	25-206	[»]
1UXS	X-ray	1.55	A	25-300	[»]
1UXW	X-ray	1.71	A	25-300	[»]
1W0V	X-ray	2.27	A	25-300	[»]
1W0W	X-ray	2.11	A	25-300	[»]
2A83	X-ray	1.40	A	25-300	[»]
2BSR	X-ray	2.30	A	25-300	[»]
2BSS	X-ray	2.00	A	25-300	[»]
2BST	X-ray	2.10	A	25-300	[»]
3B3I	X-ray	1.86	A	25-300	[»]
3B6S	X-ray	1.80	A	25-300	[»]
3BP4	X-ray	1.85	A	25-300	[»]
3BP7	X-ray	1.80	A	25-300	[»]
3CZF	X-ray	1.20	A	25-300	[»]
3D18	X-ray	1.74	A	25-300	[»]
3DTX	X-ray	2.10	A	25-300	[»]

ModBase

Search...

Protein-protein interaction databases

DIP

DIP:6188N.

Proteomic databases

PRIDE

P03989.

Genome annotation databases

Ensembl

ENSG00000206450. Homo sapiens. [Contig view]

Organism-specific databases

GeneCards

GC06M031345.
GC06Mf31371.

HGNC

HGNC:4932. HLA-B.

MIM

106300. phenotype.
142830. gene.

Orphanet

825. Ankylosing spondylarthritis.

PharmGKB

PA35056.

GenAtlas

Search...

Phylogenomic databases

HOVERGEN

P03989.

Enzyme and pathway databases

Reactome

REACT_6900. Signaling in Immune system.

Gene expression databases

Bgee

P03989.

CleanEx

HS_HLA-B.

Family and domain databases

InterPro

IPR007110. Ig-like.
IPR013783. Ig-like_fold.
IPR003006. Ig/MHC_CS.
IPR003597. Ig_C1-set.
IPR011161. MHC_I-like_Ag-recog.
IPR001039. MHC_I_a_a1/a2.
IPR010579. MHC_I_a_C.
[Graphical view]

Gene3D

G3DSA:2.60.40.10. Ig-like_fold. 1 hit.
G3DSA:3.30.500.10. MHC_I-like_Ag-recog. 1 hit.

Pfam

PF07654. C1-set. 1 hit.
PF00129. MHC_I. 1 hit.
PF06623. MHC_I_C. 1 hit.
[Graphical view]

PRINTS

PR01638. MHCCLASSI.

ProDom

PD000050. MHC_I. 1 hit.
[Graphical view] [Entries sharing at least one domain]

SMART

SM00407. IGc1. 1 hit.
[Graphical view]

PROSITE

PS50835. IG_LIKE. 1 hit.
PS00290. IG_MHC. 1 hit.
[Graphical view]

ProtoNet

Search...

Other Resources

SOURCE

Search...

Entry information

Entry name

1B27_HUMAN

Accession

Primary (citable) accession number: P03989
Secondary accession number(s): O19692 , P10317, P10318, P19373, P30467, Q08136, Q29693, Q29846, Q29961

Entry history

Integrated into UniProtKB/Swiss-Prot:	October 23, 1986
Last sequence update:	August 13, 1987
Last modified:	July 7, 2009
This is version 106 of the entry and version 2 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

HPI (Human Proteome Initiative)