Extensive remodeling of DC function by rapid maturation-induced epigenetic gene silencing
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE59365 | GEO | 2014/12/31
SECONDARY ACCESSION(S): PRJNA255188
REPOSITORIES: GEO
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Project description:Dendritic-cell (DC) maturation involves substantial remodeling of their gene-expression program. Most research has focused on inducible gene-expression networks promoting the acquisition of new functions, such as cytokine production and enhanced T-cell-stimulatory capacity. In contrast, mechanisms that modulate DC-function by inducing gene silencing remain poorly understood. Here we describe a novel primary epigenetic-silencing response that makes major contributions to the DC-maturation process. The repressed genes function in pivotal processes - including antigen-presentation, extracellular-signal detection, signal-transduction and lipid-mediator biosynthesis - underscoring the central contribution of the silencing mechanism to rapid reshaping of DC-function. Interestingly, promoters of the repressed genes exhibit a surprisingly high frequency of PU.1-occupied sites, suggesting a novel role for this transcription factor in marking genes poised for inducible repression
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