Probable non-functional immunoglobulin heavy variable 1-38-4
1_MDWNW 6_ RILFL 11_ VVATT 16_ GAHSQ 21_ VQLVQ 26_ SWAEV 31_ RKSGA 36_ SVKVS 41_ CSFSG 46_ FTITS 51_ YGIHW 56_ VQQSP 61_ GQGLE 66_ WMGWI 71_ NPGNG 76_ SPSYA 81_ KKFQG 86_ RFTMT 91_ RDMST 96_ TTAYT 101_ DLSSL 106_ TSEDM 111_AVYYY
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)