Semirandom sampling to detect differentiation-related and age-related epigenome remodeling

Experimental approaches to the study of epigenomic dysregulation in ageing

In this review, we describe how normal ageing may involve the acquisition of epigenetic errors over time, akin to the accumulation of genetic mutations with ageing. We describe how such experiments are currently performed, their limitations technically and analytically and their application to ageing research.

Developmental and epigenetic regulation of the human TLR3 gene

The receptor encoded by the human TLR3 gene recognizes double-strand RNAs (dsRNAs) associated with viral infection. TLR3 expression is strongly activated upon differentiation of monocytes to dendritic cells, and can be further stimulated by the dsRNA analog polyinosine:polycytosine (PI:C). We report evidence for developmental regulation of the TLR3 gene. In dendritic cells derived from cord blood, both differentiation- and PI:C-associated TLR3 transcriptional activation are impaired as compared to cells from adults. Consistent with relative expression patterns, chromatin states and remodeling differ between newborn and adult samples. TLR3 expression in newborn dendritic cells exhibits heterocellularity and allelic imbalance (skewing), features characteristic of cis-acting epigenetic control. These findings reveal a new source for variability in innate immune system function and provide a model for further study of perinatal epigenetic transitions during development.