In PLoS Biology this week, investigators at the German Cancer Research Center in Heidelberg describe the differential DNA methylation they've observed in the queen and worker honey bee epigenomes. The team used whole-genome sequencing followed by deep 454-sequencing in selected amplicons from eight methylated genes in the brains of queens and workers in order to see whether the differences in phenotype between these two classes of honey bees that had previously been attributed to differences in their diets could also be "[correlated] with unique brain methylomes," the authors write. Indeed, the team found that more than "550 genes show significant methylation differences between queens and workers" and propose that "DNA methylation could be linked to gene regulation in the honey bee."
Phillip Bourne, editor-in-chief of PLoS Computational Biology, and his colleagues at the University of California, San Diego, and the University of Leeds in the UK describe a "computational approach that integrates structural bioinformatics, molecular modeling, and systems biology to construct a drug-target network on a structural proteome-wide scale," which they applied to the Mycobacterium tuberculosis genome in order to generate what they've dubbed the "TB-drugome." The TB-drugome, the team shows, indicates that several TB drugs could be "repositioned to treat" the disease at "currently unexploited M.tb receptors." Bourne et al. also suggest that their TB-drugome supports "the idea that drug-target networks are inherently modular, and ... that any observed randomness is mainly caused by biased target coverage," the team writes.
Researchers at Princeton University assess "evaluating gene expression dynamics using pair-wise RNA FISH data" in PLoS Computational Biology this week. Matthieu Wyart et al. show "how and when RNA FISH data on pairs of genes can be used to reconstruct real-time dynamics" based on maximum-likelihood parameter estimates. Because mRNAs are manufactured in "short-lived bursts," the authors write, "prior knowledge of the type of dynamics — cycle versus switch — is generally required" to use RNA FISH data for this purpose.
Over in PLoS Genetics, a team led by investigators at the Baylor College of Medicine shows that "Hormad1 mutation disrupts synaptonemal complex formation, recombination, and chromosome segregation in mammalian meiosis." More specifically, using Hormad1 knockout mice and electron microscopy, the team found that "Hormad1 deficiency ... disrupts homologous chromosome pairing," the authors write, adding their supposition that "Hormad1 is likely a germ cell-specific component of the meiotic sex chromosome inactivation and transcriptional silencing complex."