Researchers at the University of North Carolina, Chapel Hill, report in a paper published online in advance in Genome Research that the "tumor-specific retargeting of an oncogenic transcription factor chimera results in dysregulation of chromatin and transcription." More specifically, the team reports its generation of an experimental system in which they addressed "questions regarding the genomic mechanisms by which chimeric transcription factors cause cancer" using EWS-FLI and its parental transcription factor, FLI1. The Chapel Hill team shows that, "through chimerism, EWS-FLI acquired the ability to alter chromatin."
Tel Aviv University's Chaim Linhart and his colleagues report on a pair of cis-regulatory motifs in promoter sequences in C. elegans that "exhibits extraordinary genomic traits," they write. "The motif pair constitutes a nearly combinatorial sequence configuration," Linhart et al. say, adding that this pair "may function in germline development, oogenesis, and early embryogenesis."
In another paper published online in advance in Genome Research this week, the European Bioinformatics Institute's Judith Zaugg and Nicholas Luscombe present a model for nucleosome positioning in S. cerevisiae, which the authors say "helps explain important properties of gene expression." Using publicly available data, the team unearthed evidence to suggest "DNA-binding transcription factors, together with chromatin-remodeling enzymes, are primarily responsible for the nucleosome architecture" in the yeast. "Our model for promoter nucleosome architecture reconciles genome-scale findings with molecular studies; in doing so, we establish principles for nucleosome positioning and gene expression that apply not only to individual genes, but across the entire genome," Zaugg and Luscombe write.