A T lymphocyte-specific transcription complex containing RUNX1 activates MHC class I expression.
MHC class I expression is subject to both tissue-specific and hormonal regulatory mechanisms. Consequently, levels of expression vary widely among tissues, with the highest levels of class I occurring in the lymphoid compartment, in T cells and B cells. Although the high class I expression in B cells is known to involve the B cell enhanceosome, the molecular basis for high constitutive class I expression in T cells has not been explored. T cell-specific genes, such as TCR genes, are regulated by a T cell enhanceosome consisting of RUNX1, CBFbeta, LEF1, and Aly. In this report, we demonstrate that MHC class I gene expression is enhanced by the T cell enhanceosome and results from a direct interaction of the RUNX1-containing complex with the class I gene in vivo. T cell enhanceosome activation of class I transcription is synergistic with CIITA-mediated activation and targets response elements distinct from those targeted by CIITA. These findings provide a molecular basis for the high levels of MHC class I in T cells.[1]References
- A T lymphocyte-specific transcription complex containing RUNX1 activates MHC class I expression. Howcroft, T.K., Weissman, J.D., Gegonne, A., Singer, D.S. J. Immunol. (2005) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg
