E-MTAB-6032
A deconvolution protocol for chip-seq reveals analogous enhancer structures on the mouse and human ribosomal RNA genes
The combination of Chromatin Immunoprecipitation and Massively Parallel Sequencing, or ChIP-Seq, has greatly advanced our genome-wide understanding of chromatin and enhancer structures. However, its resolution at any given genetic locus is limited by several factors. In applying ChIP-Seq to study the ribosomal RNA genes we found that a major limitation to resolution was imposed by the often dominant variability in sequence coverage provided by the massively parallel sequencing technology. Here we describe a simple numerical deconvolution approach that in large part corrects for this variability and significantly improves both the resolution and quantitation of protein-DNA interaction maps deduced from ChIP-Seq data. This approach has allowed us to study the in vivo organization of the RNA Polymerase I pre-initiation complexes that form at the promoters of the mouse and human ribosomal RNA genes. The data identify and map a “Spacer Promoter” and associated stalled polymerase in the intergenic spacer of the human ribosomal genes and show that a very similar Enhancer structure and organization to that found in rodents and even in lower vertebrates also exists in human.
The combination of Chromatin Immunoprecipitation and Massively Parallel Sequencing, or ChIP-Seq, has greatly advanced our genome-wide understanding of chromatin and enhancer structures. However, its resolution at any given genetic locus is limited by several factors. In applying ChIP-Seq to study the ribosomal RNA genes we found that a major limitation to resolution was imposed by the often dominant variability in sequence coverage provided by the massively parallel sequencing technology. Here we describe a simple numerical deconvolution approach that in large part corrects for this variability and significantly improves both the resolution and quantitation of protein-DNA interaction maps deduced from ChIP-Seq data. This approach has allowed us to study the in vivo organization of the RNA Polymerase I pre-initiation complexes that form at the promoters of the mouse and human ribosomal RNA genes. The data identify and map a “Spacer Promoter” and associated stalled polymerase in the intergenic spacer of the human ribosomal genes and show that a very similar Enhancer structure and organization to that found in rodents and even in lower vertebrates also exists in human.