Immunoglobulin heavy constant gamma 3 (IGHG3)
The protein contains 377 amino acids for an estimated molecular weight of 41287 Da.
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:22158414, PubMed:20176268). 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). (updated: Oct. 10, 2018)
Protein identification was indicated in the following studies:
- Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
This protein is annotated as membranous in UniProt.
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| Variant | Description |
|---|---|
| variant WIS | |
| variant OMM | |
| variant WIS | |
| variant ZUC and WIS | |
| variant WIS | |
| variant WIS | |
| variant OMM | |
| variant OMM | |
| variant OMM |
No binding partner found
Biological Process
B cell receptor signaling pathway
Complement activation
Complement activation, classical pathway
Defense response to bacterium
Fc-gamma receptor signaling pathway involved in phagocytosis
Innate immune response
Negative regulation of inflammatory response to antigenic stimulus
Opsonization
Peptide cross-linking
Phagocytosis, engulfment
Phagocytosis, recognition
Positive regulation of B cell activation
Regulation of complement activation
Retina homeostasis
Cellular Component
Blood microparticle
External side of plasma membrane
Extracellular exosome
Extracellular region
Extracellular space
Immunoglobulin complex, circulating
Molecular Function
Antigen binding
Immunoglobulin receptor binding
Serine-type endopeptidase activity
The reference OMIM entry for this protein is 147120
Immunoglobulin gm3; ighg3
See 147100. Heavy chain disease (HCD) is a naturally occurring lymphoproliferative disease in which variant monoclonal Ig heavy (H) chain fragments are found in serum or urine. Alexander et al. (1982) showed that the gene for the gamma-3 chain had undergone extensive NH(2)-terminal deletion. Cases of HCD involving immunoglobulins of the alpha and mu classes have also been described. Huck et al. (1986) cited several studies as yielding the following information on intervals between the several constant region genes of the heavy chains on chromosome 14: (qter) 5-prime--CM--4.5 kb--CD--CG3--26 kb--CG1--19 kb--CEP1--13 kb--CA1--CGP--CG2--18 kb--CG4--23 kb--CE--10 kb--CA2--3-prime (centromere). Huck et al. (1986) sequenced the CG3 gene from a member of the Tunisian family known to be homozygous for the G3m(b) allotypes. Alexander et al. (1988) pointed out that HCD proteins of 4 of the 5 immunoglobulin classes (mu, delta, gamma, and alpha) had been described. By studying a genomic clone isolated from a human lymphoid cell line of a patient with HCD protein of the gamma-3 subclass, Alexander et al. (1988) demonstrated that the aberrant serum protein was the product of 2 noncontiguous deletions in the gene and a splice correction, as well as postsynthetic NH(2)-terminal proteolysis. ... More on the omim web site
Oct. 20, 2018: Protein entry updated
Automatic update: OMIM entry 147120 was added.
Oct. 19, 2018: Additional information
Initial protein addition to the database. This entry was referenced in Bryk and co-workers. (2017).