Allelic exclusion

The second half of the chapter considers restrictions on and elaborations of the process of gene rearrangement. Allelic exclusion—the expression of an allele from only one chromosome of a pair—assures that each antibody-forming cell will produce antibodies of only a single specificity, as postulated by the clonal selection hypothesis. The preimmune repertoire is modified after exposure to antigen an... 

A consequence of a strict stochastic model is that not all B lymphocytes will exhibit allelic exclusion. If the rate of productive rearrangement is sufficiently high, there will be occasional double producers (see related discussion in Part I, Instruction and Selection). On the other hand, if the rate of productive rearrangement is low, there will be few doubles, but many cells will have only non-functional rearrangements. 

The involvement of the pre-B cell receptor in allelic exclusion at the heavy chain locus is reminiscent of the original suggestion of Alt et al. (1980a) that surface IgM... 

Bernard, O., Gough, N.M., Adams, J.M. (1981). Plasmacytomas with more than one immunoglobulin K mRNA implications for allelic exclusion. Proc. Natl. Acad. Sci. USA 78,5812-5816. 

Coleclough, C., Perry, R.P., Karjalainen, K., Weigert, M. (1981). Aberrant rearrangements contribute significantly to the allelic exclusion of immunoglobulin gene expression. Nature 290,372-378. 

Held, W., Roland, J., Raulet, D.H. (1995). Allelic exclusion of Ly49-family genes encoding class 1 MHC-specific receptors on NK cells. Nature 376, 355-358. 

Kitamura, D. Rajewsky, K. (1992). Targeted disruption of p chain membrane exon causes loss of heavy-chain allelic exclusion. Nature 356, 154-156. 

Loffert, D., Ehlich, A., Muller, W., Rajewsky, K. (1996). Surrogate light chain expression is required to establish immunoglobulin heavy chain allelic exclusion during early B cell development. Immunity 4, 133-144. 

Malissen, M., Trucy, J., Jouvin-Marche, E., Cazenave, P.-A., Scollay, R., Malissen, B. (1992). Regulation of TCR a and P gene allelic exclusion during T-cell development Immunology Today 13,315-322. 

Nussenzweig, M.C., Shaw, A.C., Sinn, E., Danner, D.B., Holmes, K.L., Morse, H.C. HI, Leder, P. (1987). Allelic exclusion in transgenic mice that express the membrane form of immunoglobulin p. Science 236, 816-819. 

Ritchie, K.A., Brinster, R.L., Storb, U. (1984). Allelic exclusion and control of endogenous immunoglobulin gene rearrangement in k transgenic mice. Nature 312,517-520. 

Walfield, A.M., Storb, U., Seising, E., Zentgraf, H. (1980). Comparison of different rearranged immunoglobulin kappa genes of a myeloma by electromicroscopy and restriction mapping of cloned DNA implications for allelic exclusion . Nucleic Acids Res. 8, 4689-4707. 

Acetylcholine 254 receptor, 256 Actinomycin D, 225 Action potential, 260 Active transport, 249 ATP requirement, 254, 257, 258 Activin, 100 Actinomycetes, 211 Allelic exclusion, 2, 34-38, 64 Allosterism, 273 Animal cap assay, 99, 100 Animal pole, 99 Antibody diversity, 1-66 Apical dominance, 226 Apical ridge, 100, 103-105 Aptamers, 177... 

Allelic exclusion is the process by which a cell uses either the gene from the maternal chromosome or the allelic gene from the paternal chromosome, but not both. Allelic exclusion occurs in genes encoding antibodies and T cell receptors. 

Nguyen MQ, Zhou Z, Marks CA, Ryba NJ, Belluscio L (2007) Prominent roles for odorant receptor coding sequences in allelic exclusion.Cell 131 (5) 1009—1017 Nishizumi H, Kumasaka K, Inoue N, Nakashima A, Sakano H (2007) Deletion of the core-H region in mice abolishes the expression of three proximal odorant receptor genes in cis.Proc Natl Acad Sci USA 104(50) 20067-20072... 

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