IGL@
Encyclopedia
Immunoglobulin lambda locus, also known as IGL@, is a region on human chromosome 22 that contains gene
s for the lambda light chains of antibodies
(or immunoglobulins).
s and initiate immune responses such as phagocytosis and the complement system. Each immunoglobulin molecule consists of two identical heavy chains and two identical light chains. There are two classes of light chains, kappa and lambda. This region represents the germline organization of the lambda light chain locus. The locus includes V (variable), J (joining), and C (constant) segments. During B cell development, a recombination event at the DNA level joins a single V segment with a J segment; the C segment is later joined by splicing at the RNA level. Recombination of many different V segments with several J segments provides a wide range of antigen recognition. Additional diversity is attained by junctional diversity, resulting from the random additional of nucleotides by terminal deoxynucleotidyltransferase, and by somatic hypermutation, which occurs during B cell maturation in the spleen and lymph nodes. Several V segments and three C segments are known to be incapable of encoding a protein and are considered pseudogenes. The locus also includes several non-immunoglobulin genes, many of which are pseudogenes or are predicted by automated computational analysis or homology to other species.
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s for the lambda light chains of antibodies
Antibody
An antibody, also known as an immunoglobulin, is a large Y-shaped protein used by the immune system to identify and neutralize foreign objects such as bacteria and viruses. The antibody recognizes a unique part of the foreign target, termed an antigen...
(or immunoglobulins).
Function
Immunoglobulins recognize foreign antigenAntigen
An antigen is a foreign molecule that, when introduced into the body, triggers the production of an antibody by the immune system. The immune system will then kill or neutralize the antigen that is recognized as a foreign and potentially harmful invader. These invaders can be molecules such as...
s and initiate immune responses such as phagocytosis and the complement system. Each immunoglobulin molecule consists of two identical heavy chains and two identical light chains. There are two classes of light chains, kappa and lambda. This region represents the germline organization of the lambda light chain locus. The locus includes V (variable), J (joining), and C (constant) segments. During B cell development, a recombination event at the DNA level joins a single V segment with a J segment; the C segment is later joined by splicing at the RNA level. Recombination of many different V segments with several J segments provides a wide range of antigen recognition. Additional diversity is attained by junctional diversity, resulting from the random additional of nucleotides by terminal deoxynucleotidyltransferase, and by somatic hypermutation, which occurs during B cell maturation in the spleen and lymph nodes. Several V segments and three C segments are known to be incapable of encoding a protein and are considered pseudogenes. The locus also includes several non-immunoglobulin genes, many of which are pseudogenes or are predicted by automated computational analysis or homology to other species.
Genes
The immunoglobulin lambda locus contains the following genes:- IGLC@ – constant group
- IGLC1 – immunoglobulin lambda constant 1 (Mcg marker)
- IGLC2IGLC2Ig lambda chain C regions is a protein that in humans is encoded by the IGLC2 gene.-Further reading:...
– immunoglobulin lambda constant 2 (Kern-Oz- marker) - IGLC3 – immunoglobulin lambda constant 3 (Kern-Oz+ marker)
- IGLC7 – immunoglobulin lambda constant 7
- IGLJ@ – joining group
- IGLJn – immunoglobulin lambda joining n
- IGLJ1, IGLJ2, IGLJ3, IGLJ6, IGLJ7
- IGLV@ – variable group
- IGLVm-n – immunoglobulin lambda variable n-m
- IGLV1-36, IGLV1-40, IGLV1-44, IGLV1-47, IGLV1-51, IGLV1-62
- IGLV2-5, IGLV2-8, IGLV2-11, IGLV2-14, IGLV2-18, IGLV2-23
- IGLV3-1, IGLV3-10, IGLV3-12, IGLV3-16, IGLV3-19, IGLV3-21, IGLV3-25, IGLV3-27
- IGLV4-3, IGLV4-60, IGLV4-69
- IGLV5-37, IGLV5-39, IGLV5-45, IGLV5-52
- IGLV6-57
- IGLV7-43
- IGLV9-49
- IGLV10-54