Epigenetic propagation of CD4 expression is established by the Cd4 proximal enhancer in helper T cells

Abstract

The stability of a lineage program (cellular memory) is dependent on mechanisms that epigenetically maintain active or repressed states of gene expression (transcriptional memory). Although epigenetic silencing of genes has been clearly demonstrated from yeast to mammals, heritable maintenance of active transcription has been less clearly defined. To investigate the potential role of active transcriptional memory during lineage diversification, we employed targeted mutation of a positive-acting cis element in the Cd4 locus to determine the impact on CD4 expression and the differentiation of CD4+ helper T cells in mice. We show that the proximal enhancer [Mp) of Cd4 is essential for CD4 expre..