In this week's early online edition of the Proceedings of the National Academy of Sciences, Northwestern University's Richard Morimoto is first author on a study that looks at protein stability in aging. Using C. elegans as test subjects, they searched for clues in protein folding sensors in different tissues, finding that age-dependent misfolding "occurs rapidly at an early stage of adulthood, and coincides with a severely reduced activation of the cytoprotective heat shock response and the unfolded protein response." This suggests that in aging-related diseases caused by changes in protein conformation, misfolding is an early molecular event.
Two papers study honeybees. In one, scientists led by May Berenbaum at the University of Illinois, Urbana-Champaign used whole-genome microarrays to compare gene expression patterns between the guts of healthy bee populations and those suffering from colony collapse disorder, which is thought to be due to pesticides or pathogens. Not only did they find "considerable variation in gene expression," they also found "unusual ribosomal RNA fragments that were conspicuously more abundant in the guts of CCD bees," they say in the abstract. The fragments may be indicative of infection by picorna-like deformed wing virus and Israeli acute paralysis virus. GenomeWeb Daily News, our sister publication, has the full scoop.
In another study, University of Illinois, Urbana-Champaign's Gene Robinson is lead author on work that links gene expression changes and aggression in honeybee behavioral evolution. Microarray gene expression analysis showed that there were expression differences for hundreds of genes in the brain between the aggressive Africanized honeybee and the more docile European honeybee. Moreover, when they exposed the gentler bee to an alarm pheromone, the gene expression levels matched the normal levels of the older Africanized species. "Based on brain gene expression profiles, Africanized bees look like they've been exposed to an alarm pheromone," senior author Gene Robinson told GenomeWeb Daily News. See the full story here.
Michael Snyder and Mark Gerstein, along with first authors Raymond Auerbach and Ghia Euskirchen, have published a new method for mapping chromatin called Sono-seq. Blending "sonication of cross-linked chromatin ... with a size-selection step and massively parallel short-read sequencing," they were able to map promoter regions of high chromatin accessibility.