USC's Sangtae Ahn was first author on work appearing in PLoS Computational Biology this week that used 'omic data to map directionality in gene networks. Using high-resolution mapping of copy number eQTLs, or quantitative trait loci regulating expression, in a mouse-hamster radiation hybrid panel, the team was able to construct "directed genetic networks." Directionality, they say, can help "dissect cause and effect in genetic networks, aiding in understanding and ultimately rational intervention."
In PLoS Genetics this week, scientists in Barcelona studied how bacteria successfully uptake new genes after horizontal gene transfer. Their work found that the plasmid R27-encoded H-NS protein has evolved to silence only the HGT genes, and not the core genome, and that H-NS needs to couple with a helper, the Hha protein, in order to modulate the expression levels of HGT genes.
Japanese scientists led work that used a novel imaging agent to watch protein-protein interactions in real time. Using a method that takes advantage of multicolor luciferases whose carboxy-terminal fragments were engineered from a click beetle luciferase, they were able to characterize in both time and space Smad1-Smad4 and Smad2-Smad4 interactions in early developing stages of a single living Xenopus laevis embryo. Their paper appears in PLoS One this week.
Also published in PLoS One, UCLA's David Wong was senior author on a paper that takes a peek into using salivary biomarkers to detect systemic diseases. Using saliva as an "emerging biofluid poised for detection of clinical diseases," they profiled mouse models of melanoma and non-small cell lung cancer for salivary biomarkers using microarrays. His team found that salivary transcriptomes were significantly altered in tumor mice versus controls and that expression of two groups of significantly altered transcription factors in salivary gland tissue of melanoma mice can possibly cause 82.6 percent of the up-regulated gene expression and 62.5 percent of the down-regulated gene expression in the saliva of these mice.