Immunoglobulin heavy constant gamma 3 (HDC) (Heavy chain disease protein) (Ig gamma-3 chain C region)
1_ASTKG 6_ PSVFP 11_ LAPCS 16_ RSTSG 21_ GTAAL 26_ GCLVK 31_ DYFPE 36_ PVTVS 41_ WNSGA 46_ LTSGV 51_ HTFPA 56_ VLQSS 61_ GLYSL 66_ SSVVT 71_ VPSSS 76_ LGTQT 81_ YTCNV 86_ NHKPS 91_ NTKVD 96_ KRVEL 101_ KTPLG 106_ DTTHT 111_ CPRCP 116_ EPKSC 121_ DTPPP 126_ CPRCP 131_ EPKSC 136_ DTPPP 141_ CPRCP 146_ EPKSC 151_ DTPPP 156_ CPRCP 161_ APELL 166_ GGPSV 171_ FLFPP 176_ KPKDT 181_ LMISR 186_ TPEVT 191_ CVVVD 196_ VSHED 201_ PEVQF 206_ KWYVD 211_ GVEVH 216_ NAKTK 221_ PREEQ 226_ YNSTF 231_ RVVSV 236_ LTVLH 241_ QDWLN 246_ GKEYK 251_ CKVSN 256_ KALPA 261_ PIEKT 266_ ISKTK 271_ GQPRE 276_ PQVYT 281_ LPPSR 286_ EEMTK 291_ NQVSL 296_ TCLVK 301_ GFYPS 306_ DIAVE 311_ WESSG 316_ QPENN 321_ YNTTP 326_ PMLDS 331_ DGSFF 336_ LYSKL 341_ TVDKS 346_ RWQQG 351_ NIFSC 356_ SVMHE 361_ ALHNR 366_ FTQKS 371_LSLSP
1: 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)