IGHG2 mutated S257A
Function
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).
Post-translational modifications
Glycosylation on Asn-176 is required for interaction with Fc receptors and ability to activate the complement pathway.
(Microbial infection) Deglycosylation on Asn-176 by S.pyogenes EndoS or Endos2 endoglucosidases prevents interaction between immunoglobulin-gamma (IgG) and Fc receptors, impairing ability to activate the complement pathway.
Cellular localization
- Isoform 1
- Secreted
- Isoform 2
- Cell membrane
- Single-pass membrane protein
Alternative names
Immunoglobulin heavy constant gamma 2, Ig gamma-2 chain C region, Ig gamma-2 chain C region DOT, Ig gamma-2 chain C region TIL, Ig gamma-2 chain C region ZIE, IGHG2