Major histocompatibility transcription

Song, Z., et al., A novel cysteine-ridi sequence-specific DNA-binding protein interacts with the conserved X-box motif of the human major histocompatibility complex dass II genes via a repeated Cys-His domain and functions as a transcriptional repressor. / Exp Med, 1994, 180(5), 1763-74. 

The coupling of superantigen—major histocompatibility complex class II to T-cell receptor swifdy results in cell-signaling cascades. ° These staphylococcal toxins can increase levels of phosphatidyl inositol from quiescent T cells, such as other mitogens, as well as elicit intracellular Ca movement that activates the protein kinase C (PKC) pathway important for interleukin-2 (IL-2) expression. " IL-2 is intimately linked to T-cell proliferation. In addition to the PKC pathway, the protein tyrosine kinase (PTK) pathway is also activated by superantigens, leading to elevated expression of various proinflammatory cytokines. Staphylococcal superantigens also potently activate transcriptional factors NF-/IB (nuclear factor kappa B) and AP-1 (activator protein-1), which subsequently elicit the synthesis of proinflammatory cytokines. " " ... 

Finally, in this brief overview of lymphocyte defects, mention should be made of mutations affecting major histocompatibility-complex (MHC) Class II molecules. These mutations affect a multiprotein transcription factor complex that regulates the expression of MHC Class II molecules (121). Affected patients have undetectable levels of MHC Class II antigens HLA-DP, DQ, and DR on the surface of monocytes and B cells. Lack of these antigen-presenting molecules leads to impaired immune response. Affected individuals have moderate lymphopenia with a severely reduced number of CD4+ T cells and normal or increased numbers of CD8+ T cells. Since MHC molecules in the thymic epithelium play a key role in positive and negative selection of primitive T cells, selection of competent T cells is also affected in the absence of MHC Class II antigens. 

Scholl, T., Ponath, P.D., and Strominger, J.L., A factor that regulates the class II major histocompatibility complex gene DPA is a member of a subfamily of zinc finger proteins that includes a Drosophila developmental control protein, Mol. Cell. Biol. 14, 8438-8450, 1994 Kaczynski, J., Cook, T., and Urrutia, R., Spl- and Kriippel-like transcription factors. Genome Biology 4, article 206, 2003. 

Fig. 1. Schematic diagram of the major histocompatibility complex on human chromosome 6. Fully expressed genes are shown in black pseudogenes (which do not express a product) are shown in white and genes of undefined or uncertain status are shaded. Distances along the chromosome are measured in units known as kilobase pairs (kbp). BAT indicates B-associated transcript TNF, tumor necrosis factor. Adapted fiom Peter and Hawkins (P3) with permission, Copyright 1992, American Medical Association.

Boss JM (1997) Regulation of transcription of MHC class II genes. Curr Opin Immunol 9 107-113 Chen M, Shirai M, Liu Z, Arichi T, Takahashi H, Nishioka M (1998) Efficient class II major histocompatibility complex presentation of endogenously synthesized hepatitis C virus core protein by Epstein-Barr virus-transformed B-lymphoblastoid cell lines to CD4+ T cells. J Virol 72 ... 

Shirayoshi Y, Burke PA, Appella E, Ozato K (1988) Interferon induced transcription of a major histocompatibility class I gene accompanies binding of inducible nuclear factors to the interferon consensus sequence. Proc Natl Acad Sci USA 85 5884 5888 Silacci P, Mottet A, Steimle V, Reith W, Mach B (1994) Developmental extinction of major histocompatibility complex class II gene expression in plasmocytes is mediated by silencing of the transactivator gene CIITA. J Exp Med 180 1329- 1336... 

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