In early online, Joe Ecker is senior author on a paper that provides the first genome-wide, single-base-resolution maps of methylated cytosines in a mammalian genome. Comparing both human embryonic stem cells and fetal fibroblasts, they found "widespread differences" between the two, including almost one-quarter of all methylation in embryonic stem cells was in a non-CG context, suggesting that embryonic stem cells may use different methylation mechanisms to affect gene regulation, they write.
Several opinion pieces appear this week. One checks in with experts and their concerns regarding the stimulus grants, another looks at the open-source Polymath Project, while a third by Cameron Neylon examines the potential of Google's open-sorce collaboration tool, Google Wave.
A special insight section explores the changing landscape of neuroscience research. Says an editorial, "The experimental landscape has changed markedly over the past few years, given the technological advances in molecular genetics, optogenetics and functional imaging." Articles cover molecular genetics and imaging technologies for circuit-based neuroanatomy, neuroscience and systems biology, and multimodal techniques for diagnosing Alzheimer's disease.
Research led by Joel Levine, a neuroscientist from the University of Toronto, has determined that Drosophila melanogaster flies use a single chemical to communicate gender and sibling identity in order to pick the right sex partners. By inserting a transgene into the fly's genome that killed cells that produced these special hydrocarbon signaling chemicals, they report that hydrocarbon-free male flies attempted copulating with each other, says a story at the BBC. Check out the accompanying video, too.