HLA-A - HLA-A Gene

HLA-A Gene

Major histocompatibility complex, class I, A

PDB rendering based on 1a1m.

Available structures

PDB

Ortholog search: PDBe, RCSB

List of PDB id codes
2XPG, 3RL1, 3RL2

Identifiers

Symbols

HLA-A; HLAA

External IDs

OMIM: 142800 MGI: 95904 HomoloGene: 128352 ChEMBL: 2632 GeneCards: HLA-A Gene

Gene Ontology
Molecular function	• receptor binding • protein binding • MHC class I receptor activity
Cellular component	• Golgi membrane • plasma membrane • integral to plasma membrane • ER to Golgi transport vesicle membrane • integral to membrane • phagocytic vesicle membrane • early endosome membrane • MHC class I protein complex • integral to lumenal side of endoplasmic reticulum membrane
Biological process	• antigen processing and presentation of peptide antigen via MHC class I • antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-dependent • antigen processing and presentation of exogenous peptide antigen via MHC class I, TAP-independent • immune response • viral reproduction • detection of bacterium • virus-host interaction • cytokine-mediated signaling pathway • antigen processing and presentation of exogenous peptide antigen via MHC class I • regulation of defense response to virus by virus • regulation of immune response • interferon-gamma-mediated signaling pathway • type I interferon-mediated signaling pathway
Sources: Amigo / QuickGO

Orthologs

Species

Human

Mouse

Entrez

3105

15007

Ensembl

ENSG00000206503

ENSMUSG00000067235

UniProt

P04439

P01898

RefSeq (mRNA)

NM_001242758.1

NM_010391.4

RefSeq (protein)

NP_001229687.1

NP_034521.1

Location (UCSC)

Chr 6:
29.91 – 29.91 Mb

Chr 17:
35.47 – 35.47 Mb

PubMed search

The HLA-A gene is part of the Human MHC complex on chromosome 6. The region is at the telomeric end of the HLA complex between the HLA-G and HLA-E genes. HLA-A gene encodes the larger, α-chain, constituent of HLA-A. Variation of HLA-A α-chain in certain ways is key to HLA function. This variation promotes diversity of class I recognition in the individual and also promotes genetic diversity in the population. This diversity allows more types of foreign, virus or cancer, antigens to be 'presented' on the cell surface, but also allows a subset of the population to survive if a new virus spreads rapidly through the population.

These changes are also key to inter-individual histocompatibility of organs and tissues. Difference in exposed structures of homologous proteins between individuals gives rise to antigen-antibody reactions when tissues are transplanted. This form of antigenicity gives rise to serotypes in tissue recipients. Refined serotypes are what scientists have used for grouping HLA.

There are many variant alleles of the gene. The HLA-A gene was discovered after a long process of determining MHC antigens. The original alleles discovered for MHC class I were not separated according to genes. The first 15 HL A1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 contained antigens from many HLA loci. HL A1, 2, 3, 9, 10, 11 were later found limited to a maximum of 2 in any given person. For example, a person could have A1, A2, A7, A8 but not A1, A2, A3, and A11 or A7, A8, A14, A15. Given the exclusion HLA-A alleles were sorted according A and B, creating HLA-A and HLA-B serotype groups, in late 1970s the first A and B isoforms were finally sequenced.

Further information: History and naming of human leukocyte antigens

Serotypes of HLA-A gene products
antigen	-	Broad antigen	Split antigens
A1		A9	A23	A24
A2		A10	A25	A26	A34
A3		A10	A43	A66
A11		A19	A29	A30	A31
A36		A19	A32	A33	A74
A80		A28	A68	A69
"HLA-" prefix trimmed from serotype names.