IGHG4

Function

The protein expressed by the IGHG4 gene is part of the constant region of immunoglobulin heavy chains. Immunoglobulins, or antibodies, are glycoproteins produced by B lymphocytes that can be membrane-bound or secreted. During humoral immunity's recognition phase, membrane-bound immunoglobulins act as receptors. When they bind a specific antigen, they trigger B lymphocytes to undergo clonal expansion and differentiate into plasma cells that secrete immunoglobulins. These secreted immunoglobulins then mediate the effector phase of humoral immunity to eliminate the bound antigens. Each immunoglobulin possesses two antigen binding sites, formed by the variable domains of a heavy chain and an associated light chain, allowing for high affinity binding to specific antigens. These variable domains undergo V-(D)-J rearrangement and may experience somatic hypermutations, facilitating affinity maturation after antigen exposure and selection. This supplementary information is collated from multiple sources and compiled automatically.

Post-translational modifications

Glycosylation on Asn-177 is required for interaction with Fc receptors and ability to activate the complement pathway.

(Microbial infection) Deglycosylation on Asn-177 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 4, Ig gamma-4 chain C region, IGHG4

Database links

swissprot:P01861 swissprot:P01857 omim:147130 omim:147120 omim:147110 omim:147100 swissprot:P01859 swissprot:P01860 entrezGene:3500 entrezGene:3501 entrezGene:3502 entrezGene:3503