Immunoglobulin kappa variable 2-24
1_MRLLA 6_ QLLGL 11_ LMLWV 16_ PGSSG 21_ DIVMT 26_ QTPLS 31_ SPVTL 36_ GQPAS 41_ ISCRS 46_ SQSLV 51_ HSDGN 56_ TYLSW 61_ LQQRP 66_ GQPPR 71_ LLIYK 76_ ISNRF 81_ SGVPD 86_ RFSGS 91_ GAGTD 96_ FTLKI 101_ SRVEA 106_ EDVGV 111_YYCMQ
1: V region of the variable domain of immunoglobulin light 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)