REST ChIP-seq in human and mouse hippocampus

The transcriptional repressor REST (RE1 Silencing Transcription Factor) is a master regulator of thousands of neuronal genes that together impart the terminally differentiated neuronal phenotype. Because of this unique feature, REST has been, and continues to be, a widely used model for understanding neurogenesis and neuronal cell function. These studies have focused primarily on murine embryonic development, but recent studies have pointed to distinct postnatal roles for REST in stroke, epilepsy, aging and cognitive decline. The function of REST in healthy human brain tissue, however, still remains poorly characterized. Here, we present deep sequencing chromatin immunoprecipitation evidence for divergent REST function in normal mouse and human postmortem adult hippocampus. In mouse, REST occupies only 221 peaks that are divided between prototypical REST target genes shared with non-neuronal cells, as well as peaks unique to the hippocampus. Surprisingly, the mouse hippocampal-unique sites are not conserved in human, which contains 1886 REST peaks unique to the hippocampus. Further, the REST peaks unique to the hippocampus represent a potentially new category of target genes encoding proteins important in the immune response. Our results suggest the possibility that REST protects against aberrant immunological responses during normal human aging and that mouse may not model this aging function.