Biomaterial Database

Creation of immunoglobulin diversity by intrachromosomal gene conversion. 1992

C B Thompson

Howard Hughes Medical Institute, University of Michigan Medical Center, Ann Arbor 48109.

Not all vertebrates create an immunoglobulin repertoire through the recombination of individual members of variable (V), diversity (D) and joining (J) gene segment families. In chickens, for example, a diverse set of immunoglobulins is created by intrachromosomal gene conversion of the single variable gene segments of the immunoglobulin heavy and light chain genes. Recent evidence from other species such as the rabbit suggests that gene conversion may be a more widespread mechanism for the creation of immunologic diversity than previously supposed.

UI	MeSH Term	Description	Entries
D007147	Immunoglobulin Light Chains	Polypeptide chains, consisting of 211 to 217 amino acid residues and having a molecular weight of approximately 22 kDa. There are two major types of light chains, kappa and lambda. Two Ig light chains and two Ig heavy chains (IMMUNOGLOBULIN HEAVY CHAINS) make one immunoglobulin molecule.	Ig Light Chains,Immunoglobulins, Light-Chain,Immunoglobulin Light Chain,Immunoglobulin Light-Chain,Light-Chain Immunoglobulins,Chains, Ig Light,Chains, Immunoglobulin Light,Immunoglobulins, Light Chain,Light Chain Immunoglobulins,Light Chain, Immunoglobulin,Light Chains, Ig,Light Chains, Immunoglobulin,Light-Chain, Immunoglobulin
D008957	Models, Genetic	Theoretical representations that simulate the behavior or activity of genetic processes or phenomena. They include the use of mathematical equations, computers, and other electronic equipment.	Genetic Models,Genetic Model,Model, Genetic
D011544	Pseudogenes	Genes bearing close resemblance to known genes at different loci, but rendered non-functional by additions or deletions in structure that prevent normal transcription or translation. When lacking introns and containing a poly-A segment near the downstream end (as a result of reverse copying from processed nuclear RNA into double-stranded DNA), they are called processed genes.	Genes, Processed,beta-Tubulin Pseudogene,Gene, Processed,Processed Gene,Processed Genes,Pseudogene,Pseudogene, beta-Tubulin,Pseudogenes, beta-Tubulin,beta Tubulin Pseudogene,beta-Tubulin Pseudogenes
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D011995	Recombination, Genetic	Production of new arrangements of DNA by various mechanisms such as assortment and segregation, CROSSING OVER; GENE CONVERSION; GENETIC TRANSFORMATION; GENETIC CONJUGATION; GENETIC TRANSDUCTION; or mixed infection of viruses.	Genetic Recombination,Recombination,Genetic Recombinations,Recombinations,Recombinations, Genetic
D002060	Bursa of Fabricius	An epithelial outgrowth of the cloaca in birds similar to the thymus in mammals. It atrophies within 6 months after birth and remains as a fibrous remnant in adult birds. It is composed of lymphoid tissue and prior to involution, is the site of B-lymphocyte maturation.	Fabricius Bursa
D002642	Chick Embryo	The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.	Embryo, Chick,Chick Embryos,Embryos, Chick
D002645	Chickens	Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.	Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D005785	Gene Conversion	The asymmetrical segregation of genes during replication which leads to the production of non-reciprocal recombinant strands and the apparent conversion of one allele into another. Thus, e.g., the meiotic products of an Aa individual may be AAAa or aaaA instead of AAaa, i.e., the A allele has been converted into the a allele or vice versa.	Polar Recombination,Polaron,Conversion, Gene,Conversions, Gene,Gene Conversions,Polar Recombinations,Polarons,Recombination, Polar,Recombinations, Polar
D005803	Genes, Immunoglobulin	Genes encoding the different subunits of the IMMUNOGLOBULINS, for example the IMMUNOGLOBULIN LIGHT CHAIN GENES and the IMMUNOGLOBULIN HEAVY CHAIN GENES. The heavy and light immunoglobulin genes are present as gene segments in the germline cells. The completed genes are created when the segments are shuffled and assembled (B-LYMPHOCYTE GENE REARRANGEMENT) during B-LYMPHOCYTE maturation. The gene segments of the human light and heavy chain germline genes are symbolized V (variable), J (joining) and C (constant). The heavy chain germline genes have an additional segment D (diversity).	Genes, Ig,Immunoglobulin Genes,Gene, Ig,Gene, Immunoglobulin,Ig Gene,Ig Genes,Immunoglobulin Gene