In a paper published online in advance in Nature this week, a team led by investigators at the University of Copenhagen presents evidence to suggest TET1 has a role in transcriptional repression, such that it "binds a significant proportion of Polycomb group target genes" and also "associates and co-localizes with the SIN3A co-repressor complex." As a result of its investigation, the team suggests that TET1 "contributes to the regulation of DNA methylation fidelity" by opposing aberrant methylation at CpG-rich sequences.
David Burns and his colleagues at the University of Massachusetts Medical School this week discuss how "CPEB and two poly(A) polymerases control miR-122 stability and p53 mRNA translation," and thus contribute to the regulation of cellular senescence in primary human diploid fibroblasts. Contrary to the popular thought that miR-122 is liver-specific, Burns et al. show that it is present in primary fibroblasts, where it is de-stabilized by Gld2 depletion.
Researchers at Rockefeller University used an over-expression screening approach to find that different viruses are targeted by unique sets of interferon-stimulated genes, and that "each viral species is susceptible to multiple antiviral genes, which together encompass a range of inhibitory activities." By testing more than 380 human interferon-stimulated genes for their inhibition of replication on several viruses, including hepatitis C, the yellow fever virus, West Nile, chikungunya, the Venezuelan equine encephalitis virus, and HIV type-1, the team uncovered "a common theme of translational inhibition for numerous effectors," it writes. "Several ISGs [interferon-stimulated genes] ... enhanced the replication of certain viruses, enhancing another layer of complexity in the highly pleiotropic type 1 interferon system."
Over in Nature Genetics, an international team led by investigators at the Stowers Institute for Medical Research in Kansas City, Mo., shows that "the binding of the developmental transcription factor Twist is highly conserved across six Drosophila species." In particular, the Stowers-led team notes that "conserved binding correlates with sequence motifs for Twist and its partners," which it says permits the "de novo discovery of their combinatorial binding."