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Details on Person UniProt:P01889 HLA-B

Class:IdReferenceGeneProduct:48971
_chainChangeLogsignal peptide:1-24 added on Fri February 6 2015;chain:25-362 added on Fri February 6 2015
_displayNameUniProt:P01889 HLA-B
_timestamp2026-02-20 22:33:03
chainsignal peptide:1-24
chain:25-362
checksum5E5A7BDE031403D6
commentFUNCTION Antigen-presenting major histocompatibility complex class I (MHCI) molecule. In complex with B2M/beta 2 microglobulin displays primarily viral and tumor-derived peptides on antigen-presenting cells for recognition by alpha-beta T cell receptor (TCR) on HLA-B-restricted CD8-positive T cells, guiding antigen-specific T cell immune response to eliminate infected or transformed cells (PubMed:23209413, PubMed:25808313, PubMed:29531227, PubMed:9620674). May also present self-peptides derived from the signal sequence of secreted or membrane proteins, although T cells specific for these peptides are usually inactivated to prevent autoreactivity (PubMed:18991276, PubMed:7743181). Both the peptide and the MHC molecule are recognized by TCR, the peptide is responsible for the fine specificity of antigen recognition and MHC residues account for the MHC restriction of T cells (PubMed:24600035, PubMed:29531227, PubMed:9620674). Typically presents intracellular peptide antigens of 8 to 13 amino acids that arise from cytosolic proteolysis via constitutive proteasome and IFNG-induced immunoproteasome (PubMed:23209413). Can bind different peptides containing allele-specific binding motifs, which are mainly defined by anchor residues at position 2 and 9 (PubMed:25808313, PubMed:29531227).FUNCTION Allele B*07:02: Displays peptides sharing a common signature motif, namely a Pro residue at position 2 and mainly a Leu anchor residue at the C-terminus (PubMed:7743181). Presents a long peptide (APRGPHGGAASGL) derived from the cancer-testis antigen CTAG1A/NY-ESO-1, eliciting a polyclonal CD8-positive T cell response against tumor cells (PubMed:29531227). Presents viral epitopes derived from HIV-1 gag-pol (TPQDLNTML) and Nef (RPQVPLRPM) (PubMed:25808313). Presents an immunodominant epitope derived from SARS-CoV-2 N/nucleoprotein (SPRWYFYYL) (PubMed:32887977). Displays self-peptides including a peptide derived from the signal sequence of HLA-DPB1 (APRTVALTA) (PubMed:7743181).FUNCTION Allele B*08:01: Presents to CD8-positive T cells viral epitopes derived from EBV/HHV-4 EBNA3 (QAKWRLQTL), eliciting cytotoxic T cell response.FUNCTION Allele B*13:02: Presents multiple HIV-1 epitopes derived from gag (RQANFLGKI, GQMREPRGSDI), nef (RQDILDLWI), gag-pol (RQYDQILIE, GQGQWTYQI) and rev (LQLPPLERL), all having in common a Gln residue at position 2 and mainly hydrophobic amino acids Leu, Ile or Val at the C-terminus. Associated with successful control of HIV-1 infection.FUNCTION Allele B*18:01: Preferentially presents octameric and nonameric peptides sharing a common motif, namely a Glu at position 2 and Phe or Tyr anchor residues at the C-terminus (PubMed:14978097, PubMed:18991276, PubMed:23749632). Presents an EBV/HHV-4 epitope derived from BZLF1 (SELEIKRY) (PubMed:23749632). May present to CD8-positive T cells an antigenic peptide derived from MAGEA3 (MEVDPIGHLY), triggering an anti-tumor immune response (PubMed:12366779). May display a broad repertoire of self-peptides with a preference for peptides derived from RNA-binding proteins (PubMed:14978097).FUNCTION Allele B*27:05: Presents to CD8-positive T cells immunodominant viral epitopes derived from HCV POLG (ARMILMTHF), HIV-1 gag (KRWIILGLNK), IAV NP (SRYWAIRTR), SARS-CoV-2 N/nucleoprotein (QRNAPRITF), EBV/HHV-4 EBNA4 (HRCQAIRKK) and EBV/HHV-4 EBNA6 (RRIYDLIEL), conferring longterm protection against viral infection (PubMed:15113903, PubMed:18385228, PubMed:19139562, PubMed:32887977, PubMed:9620674). Can present self-peptides derived from cytosolic and nuclear proteins. All peptides carry an Arg at position 2 (PubMed:1922338). The peptide-bound form interacts with NK cell inhibitory receptor KIR3DL1 and inhibits NK cell activation in a peptide-specific way, being particularly sensitive to the nature of the amino acid side chain at position 8 of the antigenic peptide (PubMed:15657948, PubMed:8879234). KIR3DL1 fails to recognize HLA-B*27:05 in complex with B2M and EBV/HHV-4 EBNA6 (RRIYDLIEL) peptide, which can lead to increased activation of NK cells during infection (PubMed:15657948). May present an altered repertoire of peptides in the absence of TAP1-TAP2 and TAPBPL (PubMed:9620674).FUNCTION Allele B*40:01: Presents immunodominant viral epitopes derived from EBV/HHV-4 LMP2 (IEDPPFNSL) and SARS-CoV-2 N/nucleoprotein (MEVTPSGTWL), triggering memory CD8-positive T cell response (PubMed:18991276, PubMed:32887977). Displays self-peptides sharing a signature motif, namely a Glu at position 2 and a Leu anchor residue at the C-terminus (PubMed:18991276).FUNCTION Allele B*41:01: Displays self-peptides sharing a signature motif, namely a Glu at position 2 and Ala or Pro anchor residues at the C-terminus.FUNCTION Allele B*44:02: Presents immunodominant viral epitopes derived from EBV/HHV-4 EBNA4 (VEITPYKPTW) and EBNA6 (AEGGVGWRHW, EENLLDFVRF), triggering memory CD8-positive T cell response (PubMed:18991276, PubMed:9620674). Displays self-peptides sharing a signature motif, namely a Glu at position 2 and Phe, Tyr or Trp anchor residues at the C-terminus (PubMed:18991276).FUNCTION Allele B*45:01: Displays self-peptides sharing a signature motif, namely a Glu at position 2 and Ala or Pro anchor residues at the C-terminus.FUNCTION Allele B*46:01: Preferentially presents nonameric peptides sharing a signature motif, namely Ala and Leu at position 2 and Tyr, Phe, Leu, or Met anchor residues at the C-terminus. The peptide-bound form interacts with KIR2DL3 and inhibits NK cell cytotoxic response in a peptide-specific way.FUNCTION Allele B*47:01: Displays self-peptides sharing a signature motif, namely an Asp at position 2 and Leu or Met anchor residues at the C-terminus.FUNCTION Allele B*49:01: Displays self-peptides sharing a signature motif, namely a Glu at position 2 and Ile or Val anchor residues at the C-terminus.FUNCTION Allele B*50:01: Displays self-peptides sharing a signature motif, namely a Glu at position 2 and Ala or Pro anchor residues at the C-terminus.FUNCTION Allele B*51:01: Presents an octameric HIV-1 epitope derived from gag-pol (TAFTIPSI) to the public TRAV17/TRBV7-3 TCR clonotype, strongly suppressing HIV-1 replication.FUNCTION Allele B*54:01: Displays peptides sharing a common signature motif, namely a Pro residue at position 2 and Ala anchor residue at the C-terminus.FUNCTION Allele B*55:01: Displays peptides sharing a common signature motif, namely a Pro residue at position 2 and Ala anchor residue at the C-terminus.FUNCTION Allele B*56:01: Displays peptides sharing a common signature motif, namely a Pro residue at position 2 and Ala anchor residue at the C-terminus.FUNCTION Allele B*57:01: The peptide-bound form recognizes KIR3DL1 and inhibits NK cell cytotoxic response. Presents HIV gag peptides (immunodominant KAFSPEVIPMF and subdominant KALGPAATL epitopes) predominantly to CD8-positive T cell clones expressing a TRAV41-containing TCR, triggering HLA-B-restricted T cell responses.FUNCTION Allele B*67:01: Displays peptides sharing a common signature motif, namely a Pro residue at position 2 and Leu anchor residue at the C-terminus.SUBUNIT Heterotrimer that consists of an alpha chain HLA-B, a beta chain B2M and a peptide (peptide-HLA-B-B2M) (PubMed:15657948, PubMed:17057332, PubMed:22020283, PubMed:24600035, PubMed:25808313, PubMed:29531227). Early in biogenesis, HLA-B-B2M dimer interacts with the components of the peptide-loading complex composed of TAPBP, TAP1-TAP2, TAPBPL, PDIA3/ERP57 and CALR (PubMed:26416272, PubMed:26439010, PubMed:9036970, PubMed:9620674). Interacts with TAP1-TAP2 transporter via TAPBP; this interaction is obligatory for the loading of peptide epitopes delivered to the ER by TAP1-TAP2 transporter (PubMed:9036970, PubMed:9620674). Interacts with TAPBPL; TAPBPL binds peptide-free HLA-B-B2M complexes or those loaded with low affinity peptides, likely facilitating peptide exchange for higher affinity peptides (PubMed:26439010). Only optimally assembled peptide-HLA-B-B2M trimer translocates to the surface of antigen-presenting cells, where it interacts with TCR and CD8 coreceptor on the surface of T cells. HLA-B (via polymorphic alpha-1 and alpha-2 domains) interacts with antigen-specific TCR (via CDR1, CDR2 and CDR3 domains) (PubMed:24600035, PubMed:29531227). One HLA-B molecule (mainly via nonpolymorphic alpha-3 domain) interacts with one CD8A homodimer (via CDR-like loop); this interaction ensures peptide-HLA-B-B2M recognition by CD8-positive T cells only (PubMed:29531227). Allele B*57:01 interacts (via Bw4 motif) with KIR3DL1 (via Ig-like C2-type domain); this interaction may interfere with peptide binding (PubMed:22020283, PubMed:25480565). Allele B*46:01 interacts with KIR2DL3 (PubMed:28514659).SUBUNIT (Microbial infection) Interacts with HTLV-1 accessory protein p12I.INTERACTION The alpha-1 domain is a structural part of the peptide-binding cleft (PubMed:25808313). Residues 101-107 determine Bw4/Bw6 motifs, which serologically distinguish HLA-B alleles. Each HLA-B allele possesses either the Bw4 or Bw6 motif. Only HLA-B alleles bearing the Bw4 epitope are recognized by NK cell inhibitory receptor KIR3DL1 (PubMed:22020283, PubMed:25480565).DOMAIN The alpha-2 domain is a structural part of the peptide-binding cleft (PubMed:25808313). Mediates the interaction with TAP1-TAP2 complex (By similarity).DOMAIN The alpha-3 Ig-like domain mediates the interaction with CD8 coreceptor.DOMAIN The VL9 peptide/epitope (VMAPRT[V/L][L/V/I/F]L) derived from the signal sequence is loaded onto HLA-E and enables HLA-E expression at the plasma membrane. Distinct VL9 peptides presented by HLA-E variably affect its recognition by KLRD1-KLRC1 or KLRD1-KLRC2 receptors on NK cells. Most HLA-B allotypes contain VL9 peptides with low affinity for HLA-E. The VL9 peptide derived from HLA-B*07, B*08, B*14, B*38, B*39, B*42 and B*48 allotypes, displays high affinity for HLA-E yet fails to drive NK cell activation. It outcompetes other VL9 peptides derived from HLA-A and HLA-C for binding to HLA-E, lowering the threshold of NK cell activation.POLYMORPHISM The most polymorphic of the mammalian genome. Polymorphic residues encode for alpha-1 and alpha-2 domains of the peptide-binding cleft, where they contribute to variations in peptide binding and TCR recognition among different alleles. The human population is estimated to have millions of HLA-B alleles. But only 17 common HLA-A alleles are considered core alleles, representing all functionally significant variation (polymorphism) in alpha-1 and alpha-2 domains. These are: B*07:02; B*08:01; B*13:02; B*15:01; B*18:01; B*27:05; B*35:01; B*37:01; B*38:01; B*40:01; B*44:02; B*45:01; B*51:01; B*54:01; B*57:01 and B*73:01. Among these, B*07:02; B*15:01; B*18:01; B*37:01; B*51:01; B*54:01; B*57:01 and B*73:01, were likely passed by introgression from archaic to modern humans. Functional alleles of more recent origin (non-core) were derived by recombination (PubMed:28650991). The sequence shown is that of B*07:02. The sequences of core alleles and common representative alleles of serologically distinct allele groups are described as variants of B*07:02. Allelic variations of HLA-B signal peptide regulate HLA-E recognition by KLRD1-KLRC1 and KLRD1-KLRC2 receptors in viral infection and tumorigenesis by affecting its processing and by changing the affinity of HLA-E-VL9 complex for KLRD1-KLRC1 and KLRD1-KLRC2 receptors.DISEASE Disease susceptibility is associated with variants affecting the gene represented in this entry. Increased susceptibility to Stevens-Johnson syndrome is conferred by allele B*15:02.DISEASE Disease susceptibility is associated with variants affecting the gene represented in this entry. A restricted number of HLA-B*27 subtypes can be associated with ankylosing spondylitis and other B*27-related diseases, and an elevated frequency of the B*27:02 allele in ankylosing spondylitis patients is identified. The allele B*27:07 seems to have a protective role in some populations because it was found only in the healthy controls.DISEASE There is evidence that HLA-B*51 is associated with susceptibility to Behcet disease (BD). However, it is not certain whether HLA-B*51 itself or a closely linked gene is responsible for susceptibility. The world distribution of HLA-B*51 in healthy people corresponds to the global distribution of BD; in Southern hemisphere countries (Africa, South Pacific, etc.) and in some parts of Europe, the prevalence of HLA-B*51 in healthy people is low or null, corresponding to a low prevalence of BD. The wide variation that exists in the relative risk of HLA-B*51 would support other nongenetic risk factors.DISEASE The presence of allele B*57:01 is associated with increased susceptibility to abacavir hypersensitivity [MIM:142830] in HIV-1 patients.DISEASE Allele group B*08 is associated with increased susceptibility to rheumatoid arthritis, where affected individuals have antibodies to cyclic citrullinated peptide (anti-CCP-positive rheumatoid arthritis).
descriptionrecommendedName: HLA class I histocompatibility antigen, B alpha chain alternativeName: Human leukocyte antigen B shortName: HLA-B
geneNameHLA-B
HLAB
identifierP01889
isSequenceChangedFALSE
keyword3D-structure
Adaptive immunity
Cell membrane
Direct protein sequencing
Disulfide bond
Endoplasmic reticulum
Glycoprotein
Host-virus interaction
Immunity
Innate immunity
Membrane
MHC I
Phosphoprotein
Proteomics identification
Reference proteome
Signal
Transmembrane
Transmembrane helix
modified[InstanceEdit:9836292] Weiser, Joel, 2023-05-25
[InstanceEdit:9841277] Weiser, Joel
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9862192] Weiser, Joel, 2024-02-26
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9948485] Weiser, Joel, 2025-05-21
[InstanceEdit:9983091] Weiser, Joel, 2026-02-20
nameHLA-B
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8962423] ENSEMBL:ENSG00000234745 HLA-B [Homo sapiens]
secondaryIdentifierHLAB_HUMAN
A0A2I6Q7B5
B0V0B8
G3GN01
O02862
O02956
O02957
O02960
O19555
O19556
O19595
O19615
O19624
O19625
O19627
O19641
O19651
O19675
O19692
O19758
O19779
O19783
O46702
O62897
O62901
O62915
O62917
O62919
O77933
O77959
O78053
O78138
O78160
O78163
O78172
O78173
O78180
O78217
O95730
O98140
P01890
P03989
P10317
P10318
P10319
P10320
P18463
P18464
P18465
P19373
P30460
P30461
P30462
P30463
P30464
P30465
P30466
P30467
P30468
P30469
P30470
P30471
P30472
P30473
P30474
P30475
P30476
P30477
P30478
P30479
P30480
P30481
P30482
P30483
P30484
P30485
P30486
P30487
P30488
P30489
P30490
P30491
P30492
P30493
P30494
P30495
P30496
P30497
P30498
P30513
P30685
P79489
P79490
P79496
P79504
P79523
P79524
P79542
P79555
Q04826
Q08136
Q29633
Q29636
Q29638
Q29661
Q29665
Q29678
Q29679
Q29681
Q29693
Q29695
Q29697
Q29718
Q29742
Q29749
Q29762
Q29764
Q29829
Q29836
Q29842
Q29845
Q29846
Q29847
Q29848
Q29850
Q29851
Q29852
Q29854
Q29855
Q29857
Q29858
Q29861
Q29924
Q29925
Q29933
Q29935
Q29936
Q29940
Q29953
Q29961
Q29982
Q30173
Q30198
Q31603
Q31610
Q31612
Q31613
Q546L8
Q546M4
Q5JP37
Q5QT24
Q5RIP1
Q5SRJ2
Q5TK76
Q5TK77
Q860I4
Q861B5
Q8HWF0
Q8MGQ3
Q8MHN4
Q8SNC5
Q95343
Q95344
Q95365
Q95369
Q95392
Q95HA3
Q95HA8
Q95HM9
Q95IA6
Q95IB8
Q95IH5
Q95J00
Q96IT9
Q9BCM6
Q9BCM7
Q9BCM8
Q9BD06
Q9BD38
Q9BD43
Q9GIL3
Q9GIM3
Q9GIX1
Q9GIY5
Q9GIZ0
Q9GIZ9
Q9GJ00
Q9GJ17
Q9GJ20
Q9GJ23
Q9GJ31
Q9GJF0
Q9GJM7
Q9MX21
Q9MY37
Q9MY42
Q9MY43
Q9MY61
Q9MY75
Q9MY78
Q9MY79
Q9MY84
Q9MY92
Q9MY93
Q9MY94
Q9MYB8
Q9MYC3
Q9MYC7
Q9MYF4
Q9MYG1
Q9TP35
Q9TP36
Q9TP37
Q9TP95
Q9TPQ7
Q9TPQ9
Q9TPR2
Q9TPR4
Q9TPS6
Q9TPT2
Q9TPT4
Q9TPT6
Q9TPV2
Q9TQG1
Q9TQH3
Q9TQH6
Q9TQH7
Q9TQH8
Q9TQH9
Q9TQM2
Q9TQN4
Q9TQN6
Q9UQS8
Q9UQT0
sequenceLength362
species[Species:48887] Homo sapiens
(referenceEntity)[EntityWithAccessionedSequence:167756] class I MHC B7 [plasma membrane] [Homo sapiens]
[EntityWithAccessionedSequence:983073] class I MHC B7 [lumenal side of endoplasmic reticulum membrane] [Homo sapiens]
[EntityWithAccessionedSequence:983362] class I MHC B7 [ER to Golgi transport vesicle membrane] [Homo sapiens]
[EntityWithAccessionedSequence:983379] class I MHC B7 [Golgi membrane] [Homo sapiens]
[EntityWithAccessionedSequence:1236753] class I MHC B7 [phagocytic vesicle membrane] [Homo sapiens]
[EntityWithAccessionedSequence:1236872] class I MHC B7 [early endosome membrane] [Homo sapiens]
[EntityWithAccessionedSequence:6804794] class I MHC B7 [secretory granule membrane] [Homo sapiens]
[EntityWithAccessionedSequence:8863942] class I MHC B7 [recycling endosome membrane] [Homo sapiens]
(referenceSequence)[GroupModifiedResidue:9985195] N4-(N-acetylamino)glucosyl-L-asparagine (N-(α-Glc-(1→3)-α-Man-(1→2)-α-Man-(1→2)-α-Man-(1→3)-(α-Man-(1→2)-α-Man-(1→3)-(α-Man-(1→2)-α-Man-(1→6))-α-Man-(1→6))-β-Man-(1→4)-β-GlcNAc-(1→4)-β-GlcNAc)-L-Asn residue) at 110
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No pathways have been reviewed or authored by UniProt:P01889 HLA-B (48971)