Probable non-functional immunoglobulin lambda variable 5-48
1_MAWTP 6_ LLLLF 11_ LSHCT 16_ GSLSQ 21_ AVLTQ 26_ PTSLS 31_ ASPGA 36_ SARLT 41_ CTLRS 46_ GISVG 51_ SYRIY 56_ WYQQK 61_ PGSPP 66_ RYLLN 71_ YYSDS 76_ DKHQG 81_ SGVPS 86_ RFSGS 91_ KDAST 96_NAGIL
1: Probable non-functional open reading frame (ORF) of V region of the variable domain of immunoglobulin light 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)