In PLOS Genetics, researchers from Singapore and China describe expression patterns, transcription factors, and regulatory marks that appear to be involved in the process of mouse stem cell differentiation into brown adipocytes, or brown fat cells. Using RNA sequencing, microarrays, and chromatin immunoprecipitation sequencing, the team tracked messenger RNA, long non-coding RNA, microRNA, and chromatin marks as it prompted a mouse mesenchymal stem cell line to differentiate into brown adipocytes. "[W]e provide a comprehensive reference map for the dynamic epigenome and transcriptome during [brown adipocyte] differentiation, propose a conceptual model of brown gene regulation, and also show that comparative transcriptomic and epigenomic analysis is a powerful tool for the discovery of novel regulators, resulting in the identification of four activators of [brown adipocyte] differentiation in this study," the authors write.
A team from Hainan Medical College and elsewhere investigate potential ties between longevity and variants in the insulin signaling pathway regulatory gene FOXO3 in the Chinese population for a paper in PLOS One. When they genotyped 18 FOXO3 SNPs in more than 600 exceptionally long-lived individuals and almost 850 younger control individuals, the researchers saw nominally significant ties between longevity in males and five SNPs in FOXO3, including four variants described previously. On the other hand, they did not detect associations for all of the previously described longevity variants in FOXO3 in females.
Expression of herpesvirus genes appears to rise alongside increasing viral genome number in individual host cells, according to a study in PLOS Pathogens. Investigators from Tel Aviv University used fluorescence-expressing genetically tagged herpes recombinant constructs to track viral gene expression and the 'number of incoming viral genomes replicating' in three monkey or human cell types. Their results revealed variation in the number of herpesvirus genomes in individual cells, both within and between cell types. While viral gene expression coincided with virus genome numbers, they note that enhanced expression of housekeeping genes did not correspond to viral gene expression, prompting the authors to argue that "the stochastic nature of viral infection and host cell determinants contribute together to the variability observed among infected cells."