Nucleosome organization in the Drosophila genome
Nucleosome organization in the Drosophila genome
Comparative genomics of nucleosome positions provides a powerful means for understand-ing how the organization of chromatin and the transcription machinery co-evolve.  Here we produce a high resolution reference map of H2A.Z and bulk nucleosome locations across the genome of the fly D. melanogaster, and compare it to that from the yeast S. cerevisiae.  Like Saccharomyces, Drosophila nucleosomes are organized around active transcription start sites in a canonical -1, NFR (nucleosome-free region),  1 arrangement.  However, Drosophila does not incorporate H2A.Z into the -1 nucleosome and does not bury its transcriptional start site in the  1 nucleosome.  At thousands of genes, RNA polymerases II engages the  1 nucleosome and pauses.  How the transcription initiation machinery contends with the  1 nucleosome appears to be fundamentally different between lower and higher eukaryotes.
Conserved and unique organization of nucleosomes and putative regulatory elements in the Drosophila genome