Probable non-functional immunoglobulin heavy variable 3-38
1_MQFVL 6_ SWVFL 11_ VGILK 16_ GVQCE 21_ VQLVE 26_ SGGGL 31_ VQPRG 36_ SLRLS 41_ CAASG 46_ FTVSS 51_ NEMSW 56_ IRQAP 61_ GKGLE 66_ WVSSI 71_ SGGST 76_ YYADS 81_ RKGRF 86_ TISRD 91_ NSKNT 96_ LYLQM 101_ NNLRA 106_ EGTAV 111_YYCAR
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)