Probable non-functional immunoglobulin heavy variable 7-81
1_MDWTW 6_ SILFL 11_ VAAAT 16_ GTYSQ 21_ VQLVQ 26_ SGHEV 31_ KQPGA 36_ SVKVS 41_ CKASG 46_ YSFTT 51_ YGMNW 56_ VPQAP 61_ GQGLE 66_ WMGWF 71_ NTYTG 76_ NPTYA 81_ QGFTG 86_ RFVFS 91_ MDTSA 96_ STAYL 101_ QISSL 106_ KAEDM 111_AMYYC
1: Probable non-functional open reading frame (ORF) of V region of the variable domain of immunoglobulin heavy chains (PubMed:24600447). Non-functional ORF generally cannot participate in the synthesis of a productive immunoglobulin chain due to altered V-(D)-J or switch recombination and/or splicing site (at mRNA level) and/or conserved amino acid change (protein level) (PubMed:9619395). 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)