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Details on Person UniProt:P01876 IGHA1

Class:IdReferenceGeneProduct:49868
_chainChangeLogchain:-353 added on Fri February 6 2015;chain:1-353 for 49868 removed on Fri May 5 2023;chain:1-398 for 49868 added on Fri May 5 2023
_displayNameUniProt:P01876 IGHA1
_timestamp2025-08-15 21:23:26
chainchain:1-398
checksumB317D8CD4F29D5F3
commentFUNCTION Constant region of immunoglobulin heavy chains. Immunoglobulins, also known as antibodies, are membrane-bound or secreted glycoproteins produced by B lymphocytes. In the recognition phase of humoral immunity, the membrane-bound immunoglobulins serve as receptors which, upon binding of a specific antigen, trigger the clonal expansion and differentiation of B lymphocytes into immunoglobulins-secreting plasma cells. Secreted immunoglobulins mediate the effector phase of humoral immunity, which results in the elimination of bound antigens (PubMed:20176268, PubMed:22158414). The antigen binding site is formed by the variable domain of one heavy chain, together with that of its associated light chain. Thus, each immunoglobulin has two antigen binding sites with remarkable affinity for a particular antigen. The variable domains are assembled by a process called V-(D)-J rearrangement and can then be subjected to somatic hypermutations which, after exposure to antigen and selection, allow affinity maturation for a particular antigen (PubMed:17576170, PubMed:20176268). Ig alpha is the major immunoglobulin class in body secretions (PubMed:2241915).SUBUNIT Immunoglobulins are composed of two identical heavy chains and two identical light chains; disulfide-linked (PubMed:20176268). Monomeric or polymeric (PubMed:2241915). Part of the secretory IgA (sIgA) complex that consists of two, four or five IgA monomers, and two additional non-Ig polypeptides, namely the JCHAIN and the secretory component (the proteolytic product of PIGR).SUBCELLULAR LOCATION 3-Hydroxykynurenine, an oxidized tryptophan metabolite that is common in biological fluids, reacts with alpha-1-microglobulin to form heterogeneous polycyclic chromophores including hydroxanthommatin. The chromophore reacts with accessible cysteines forming non-reducible thioether cross-links with Ig alpha-1 chain C region Cys-352.PTM N- and O-glycosylated. N-glycan at Asn-144: Hex5HexNAc4.POLYMORPHISM There are several alleles. The sequence shown is that of IMGT allele IGHA1*02.DISEASE A chromosomal aberration involving IGHA1 is found in multiple myeloma (MM) cell lines. Translocation t(1;14)(q21;q32) that forms a FCRL4-IGHA1 fusion protein.CAUTION For an example of a full-length immunoglobulin alpha heavy chain see AC P0DOX2.SEQUENCE CAUTION Truncated N-terminus.
descriptionrecommendedName: fullName evidence="15 20"Immunoglobulin heavy constant alpha 1 alternativeName: fullName evidence="21"Ig alpha-1 chain C region alternativeName: fullName evidence="22"Ig alpha-1 chain C region BUR alternativeName: fullName evidence="23"Ig alpha-1 chain C region TRO
geneNameIGHA1
identifierP01876
isSequenceChangedFALSE
keyword3D-structure
Adaptive immunity
Alternative splicing
Cell membrane
Chromophore
Chromosomal rearrangement
Direct protein sequencing
Disulfide bond
Glycoprotein
Immunity
Immunoglobulin
Immunoglobulin domain
Membrane
Proteomics identification
Reference proteome
Secreted
Transmembrane
Transmembrane helix
modified[InstanceEdit:84067] Schmidt, EE, 2003-12-18 04:29:09
[InstanceEdit:143527] Schmidt, EE, 2004-11-12 07:45:10
[InstanceEdit:217385] Schmidt, EE, 2008-03-27 06:23:53
[InstanceEdit:354386] Schmidt, EE, 2008-06-18 04:45:12
[InstanceEdit:384350] Kanapin, AA, 2008-11-26 14:00:39
[InstanceEdit:392885] Kanapin, AA, 2009-03-09 12:07:18
[InstanceEdit:400710] Schmidt, EE, 2009-03-25 05:33:35
[InstanceEdit:423310] Kanapin, AA
[InstanceEdit:435478] Kanapin, AA
[InstanceEdit:435871] Kanapin, AA
[InstanceEdit:447347] Kanapin, AA
[InstanceEdit:525883] Kanapin, AA
[InstanceEdit:613449] Kanapin, AA
[InstanceEdit:797602] Kanapin, AA
[InstanceEdit:937368] Yung, CK
[InstanceEdit:1042053] Yung, CK
[InstanceEdit:1220657] Yung, CK
[InstanceEdit:1300696] Yung, CK
[InstanceEdit:1301627] Yung, CK
[InstanceEdit:1551960] Weiser, JD
[InstanceEdit:1995863] Weiser, JD
[InstanceEdit:2132304] Weiser, JD
[InstanceEdit:2265580] Weiser, JD
[InstanceEdit:4341137] Weiser, JD
[InstanceEdit:5433710] Weiser, JD
[InstanceEdit:5618415] Weiser, JD
[InstanceEdit:5634237] Weiser, JD
[InstanceEdit:5673015] Weiser, JD
[InstanceEdit:8856987] Weiser, JD
[InstanceEdit:8987656] Weiser, JD
[InstanceEdit:9037114] Weiser, JD
[InstanceEdit:9616384] Weiser, JD
[InstanceEdit:9637257] Weiser, JD
[InstanceEdit:9657908] Weiser, JD
[InstanceEdit:9676415] Weiser, JD
[InstanceEdit:9688885] Weiser, JD
[InstanceEdit:9698430] Weiser, JD
[InstanceEdit:9706439] Weiser, JD
[InstanceEdit:9715482] Weiser, JD
[InstanceEdit:9730071] Weiser, JD
[InstanceEdit:9750299] Weiser, JD
[InstanceEdit:9834092] Weiser, Joel
[InstanceEdit:9841277] Weiser, Joel
[InstanceEdit:9852000] Weiser, Joel, 2023-11-03
[InstanceEdit:9917590] Weiser, Joel, 2024-08-09
[InstanceEdit:9926675] Weiser, Joel, 2024-11-03
[InstanceEdit:9963647] Weiser, Joel, 2025-08-15
nameIGHA1
referenceDatabase[ReferenceDatabase:2] UniProt
referenceGene[ReferenceDNASequence:8958510] ENSEMBL:ENSG00000211895 IGHA1 [Homo sapiens]
[ReferenceDNASequence:8958182] ENSEMBL:ENSG00000282633 IGHA1 [Homo sapiens]
secondaryIdentifierIGHA1_HUMAN
A0A286YEY1
sequenceLength398
species[Species:48887] Homo sapiens
(isoformParent)[ReferenceIsoform:9834116] UniProt:P01876-1 IGHA1 [Homo sapiens]
[ReferenceIsoform:9834117] UniProt:P01876-2 IGHA1 [Homo sapiens]
(referenceEntity)[EntityWithAccessionedSequence:1478809] IGHA1 [extracellular region] [Homo sapiens]
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No pathways have been reviewed or authored by UniProt:P01876 IGHA1 (49868)