FLICKR, NATHAN READINGDevelopers of a relatively new sequencer realized the machine’s ability to detect methylation and other modifications to bacterial DNA based on a slight time delay in the synthesis of the new strand. Now, researchers are applying the technique broadly to differentiate closely related bacterial strains, to better understand variation among pathogens, and to understand the role of DNA modification in disease virulence and spread by mapping the epigenomes of emerging pathogens.
“It’s like you’ve been in a closed room for a long time, and you open the window and look out,” Nobel Laureate Richard Roberts, chief scientific officer at New England Biolabs, told The Scientist. “And there’s a whole lot of stuff out there, and you don’t know where to look.”
CELL/TACHIBANA ET AL.First there were human embryonic stem cells (hESCs), but they came with a suite of ethical concerns—namely, the need to destroy human embryos to obtain them. Then there were induced pluripotent stem cells (iPSCs), derived from adult cells that had been de-differentiated into a ESC-like state. Now, researchers have presented a third option: hESCs produced via nuclear transfer (NT-hESCs), or the transfer of the nucleus from an adult cell into a human egg whose nucleus has been removed. The new technique may avoid the genetic and epigenetic abnormalities of iPSCs, and could have implications for treating mitochondrial disease, as the nuclear transfer results in a cell with a new set of mitochondria.
Preventing and rehabilitating misconduct: two opinions
WIKIMEDIA, SCHAAR HELMUTDespite more than 2 decades of widespread Responsible Conduct in Research (RCR) training programs for graduate students and postdocs, scientific misconduct is still on the rise. Clearly, it’s not working, argues James Hicks, a comparative and evolutionary physiologist at the University of California, Irvine. Meanwhile, Saint Louis University’s James DuBois and colleagues are looking to salvage the careers of those found guilty of misconduct. His REPAIR (Restoring Professionalism and Integrity in Research) program, which will host its second workshop this month, is “aimed at helping researchers make better professional decisions by anticipating consequences of actions and effectively managing stress, self-serving biases, compliance obligations, and challenges in the workplace.” But some researchers remain skeptical that the program will be successful, or that rule breakers deserve a second chance at all.
MAURICIO ANTONTwo new fossils uncovered in 25-million-year-old sediments provide clues regarding the split of apes, including humans, from Old World monkeys, such as baboons and macaques. That split is believed to have occurred between 25 and 30 million years ago, and previously the oldest fossils in these groups dated only to 20 million years ago. The new fossils—a molar belonging to the oldest known Old World monkey or cercopithecoid, and a jawbone and four teeth belonging to a new species—suggest that the split occurred when the climate was warming and the landscape was undergoing the beginnings of a drastic change that would form the Eastern African Rift from the formally flat Tanzanian plains. These changes could have resulted in new habitats and fueled primate diversification.
WIKIMEDIA, RAMAMore adventurous mice—that is, those that explored a complex environment more—grew more new neurons than their genetically identical counterparts, according to new research. The findings suggest that brain plasticity can be shaped by experience, which may influence the development of individuality.
WIKIMEDIA, MICHAEL HANSELMANNHigh-resolution computer tomography (CT) scans reveal the details of the painted lady butterfly’s transformation from a caterpillar to a flying insect.
Other news in life science:
The scientist who sued the Nobel committee is now suing Nobel winner Shinya Yamanaka.
The justices unanimously upheld Monsanto’s patent rights on Roundup Ready seeds.
Symbiotic fungi on the roots of bean plants can act as an underground signaling network, transmitting early warnings of impending aphid attacks.
Researchers track DNA modifications and gene expression in stem cells as they differentiate.
Members of Congress have suggested that the President should be able to pick a US Science Laureate.
The cost of DNA sequencing has gotten more expensive for the first time since records have been kept.