Immunoglobulin heavy variable 7-4-1
1_MDWTW 6_ RILFL 11_ VAAAT 16_ GAHSQ 21_ VQLVQ 26_ SGSEL 31_ KKPGA 36_ SVKVS 41_ CKASG 46_ YTFTS 51_ YAMNW 56_ VRQAP 61_ GQGLE 66_ WMGWI 71_ NTNTG 76_ NPTYA 81_ QGFTG 86_ RFVFS 91_ LDTSV 96_ STAYL 101_ QICSL 106_ KAEDT 111_AVYYC
1: V region of the variable domain of immunoglobulin heavy chains that participates in the antigen recognition (PubMed:24600447). 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)