A targeted mutation at the T-cell receptor alpha/delta locus impairs T-cell development and reveals the presence of the nearby antiapoptosis gene Dad1.
AUTOR(ES)
Hong, N A
RESUMO
Locus control regions are cis gene regulatory elements comprised of DNase I-hypersensitive sites. These regions usually do not stimulate transcription outside of a chromosomal context, and therefore their ability to regulate the expression of genes is thought to occur through the modification of chromatin accessibility. A locus control region is located downstream of the T-cell receptor (TCR) alpha/delta locus on mouse chromosome 14. This locus control region is known to drive T-cell-specific TCR alpha transcription in transgenic mice. In this report, we describe a targeted deletion of this locus control region and show that this mutation acts at a critical checkpoint in alphabeta T-cell development, between the TCR-intermediate and TCR-high stages. Our analysis further reveals that the antiapoptosis gene Dad1 is at the 3' end of the TCR alpha/delta locus and that Dad1 is required for embryogenesis. We show that mouse Dad1 has a broader expression pattern than the TCR genes, in terms of both tissue and temporal specificity. Finally, we report that the chromatin between TCR alpha and Dad1 is DNase I hypersensitive in a variety of cell types, thus correlating with Dad1 expression and raising the possibility that Dad1 regulatory sequences reside in this region.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=232063Documentos Relacionados
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