Biomaterial Database

Developmental regulation of V(D)J recombination and lymphocyte differentiation. 1996

D M Willerford, and W Swat, and F W Alt

Howard Hughes Medical Institute, The Children's Hospital, Boston, Massachusetts 02115, USA. dwiller@u.washington.edu

Recent insights into the mechanism of V(D)J recombination have clarified the direct role of the products of the recombination-activating genes Rag-1 and Rag-2 in site-specific DNA cleavage at recombination signal sequences and have identified components of the general DNA double-strand break repair pathway that participate in the rejoining of the Rag-1 and Rag-2-cut receptor gene segments. The V(D)J reaction is restricted to particular antigen receptor loci in a lineage-specific and stage-specific manner. This specificity appears to involve cis-regulatory elements, some of which also regulate transcription of the germline antigen receptor loci. Early developmental steps in the T and B lineages - including phenotypic differentiation, expansion of precursors, and selection processes - are effected in a stepwise fashion by signals generated, at least in part, by the products of the functionally rearranged antigen receptor genes themselves.

UI	MeSH Term	Description	Entries
D008214	Lymphocytes	White blood cells formed in the body's lymphoid tissue. The nucleus is round or ovoid with coarse, irregularly clumped chromatin while the cytoplasm is typically pale blue with azurophilic (if any) granules. Most lymphocytes can be classified as either T or B (with subpopulations of each), or NATURAL KILLER CELLS.	Lymphoid Cells,Cell, Lymphoid,Cells, Lymphoid,Lymphocyte,Lymphoid Cell
D008954	Models, Biological	Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment.	Biological Model,Biological Models,Model, Biological,Models, Biologic,Biologic Model,Biologic Models,Model, Biologic
D002454	Cell Differentiation	Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.	Differentiation, Cell,Cell Differentiations,Differentiations, Cell
D004254	DNA Nucleotidyltransferases	Enzymes that catalyze the incorporation of deoxyribonucleotides into a chain of DNA. EC 2.7.7.-.	Nucleotidyltransferases, DNA
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001402	B-Lymphocytes	Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.	B-Cells, Lymphocyte,B-Lymphocyte,Bursa-Dependent Lymphocytes,B Cells, Lymphocyte,B Lymphocyte,B Lymphocytes,B-Cell, Lymphocyte,Bursa Dependent Lymphocytes,Bursa-Dependent Lymphocyte,Lymphocyte B-Cell,Lymphocyte B-Cells,Lymphocyte, Bursa-Dependent,Lymphocytes, Bursa-Dependent
D013601	T-Lymphocytes	Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.	T Cell,T Lymphocyte,T-Cells,Thymus-Dependent Lymphocytes,Cell, T,Cells, T,Lymphocyte, T,Lymphocyte, Thymus-Dependent,Lymphocytes, T,Lymphocytes, Thymus-Dependent,T Cells,T Lymphocytes,T-Cell,T-Lymphocyte,Thymus Dependent Lymphocytes,Thymus-Dependent Lymphocyte
D015329	Gene Rearrangement, T-Lymphocyte	Ordered rearrangement of T-cell variable gene regions coding for the antigen receptors.	Gene Rearrangement, T-Cell Antigen Receptor,T-Cell Gene Rearrangement,T-Lymphocyte Gene Rearrangement,Gene Rearrangement, T-Cell,Gene Rearrangement, T Cell,Gene Rearrangement, T Cell Antigen Receptor,Gene Rearrangement, T Lymphocyte,Gene Rearrangements, T-Cell,Gene Rearrangements, T-Lymphocyte,Rearrangement, T-Cell Gene,Rearrangement, T-Lymphocyte Gene,Rearrangements, T-Cell Gene,Rearrangements, T-Lymphocyte Gene,T Cell Gene Rearrangement,T Lymphocyte Gene Rearrangement,T-Cell Gene Rearrangements,T-Lymphocyte Gene Rearrangements
D015398	Signal Transduction	The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.	Cell Signaling,Receptor-Mediated Signal Transduction,Signal Pathways,Receptor Mediated Signal Transduction,Signal Transduction Pathways,Signal Transduction Systems,Pathway, Signal,Pathway, Signal Transduction,Pathways, Signal,Pathways, Signal Transduction,Receptor-Mediated Signal Transductions,Signal Pathway,Signal Transduction Pathway,Signal Transduction System,Signal Transduction, Receptor-Mediated,Signal Transductions,Signal Transductions, Receptor-Mediated,System, Signal Transduction,Systems, Signal Transduction,Transduction, Signal,Transductions, Signal