BENCE VIOLAScientists from the Max Planck Institute for Evolutionary Anthropology and colleagues who sequenced and analyzed DNA from a female Neanderthal toe bone unearthed in Siberia suggest that the individual’s parents were close relatives and that such inbreeding was prevalent among her recent ancestors. Comparative analyses also showed that interbreeding occurred between Neanderthals and other hominin groups, including early modern humans.
The study provides “good evidence that there’s been constant interbreeding between different human groups all through prehistory,” said Milford Wolpoff, a professor of anthropology at the University of Michigan who was not involved in the study.
WIKIPEDIA, SCOTT ZONAThe genome of the sister species of all flowering plants will help scientists understand the ancient origins of angiosperms, according to researchers who sequenced the understory tree Amborella trichopoda this week. “The traits that Amborella shares with the other angiosperms can be interpreted as primitive traits that were present in their shared ancestor,” said Claude dePamphilis from Pennsylvania State University, one of the project’s leaders. “Now that we have Amborella’s genome, we can infer those traits and get the first real insights into what that common ancestor was like, genetically.”
WIKIMEDIA, ROBERT M. HUNTIn part due to the lengths of primary cilia, the topography of the surface on which mesenchymal stem cells grow on can influence how they develop and differentiate, researchers from Queen Mary University of London reported this week (December 18). “This intricate study is a wonderful contribution to the growing body of evidence demonstrating the powerful role of the primary cilium in regulating stem cell differentiation,” David Hoey, a biomedical engineer at the University of Limerick in Ireland who was not involved in the study, told The Scientist.
FLICKR, NIAIDTwo papers published this week (December 19) describe the molecular mechanisms that cause the HIV-inflicted death of most CD4 T cells in lymphoid tissues during infection. Two teams have now shown that the vast majority of the T cells, despite their ability to resist full infection by HIV, respond to the presence of viral DNA by sacrificing themselves via pyroptosis, which attracts more such cells to the area to die and ultimately weakens the immune system.
“This cell-death pathway links the two signatures of HIV disease progression—that is, CD4 T cell-depletion and chronic inflammation—for the first time,” said Warner Greene from the Gladstone Institutes in San Francisco, who led one of the studies.
WIKIMEDIA, BEV SYKESMice fed bacteria-rich dust produced by the presence of dogs show changes in their gut microbes that that prevented their immune systems from overreacting to airborne allergens, researchers have shown. “It’s a neat study, and it’s encouraging to see that they can identify single Lactobacilli that are involved in moderating the immune response,” said Brett Finlay, a microbiologist from the University of British Columbia, in an e-mail to The Scientist.
DAN DRECKTRAH AND SCOTT SAMUELSA protein expressed in Borrelia burgdorferi, the spirochete bacterium that causes Lyme disease, is necessary for both tick transmission of the microbe and for infection of a mouse host, researchers showed this week (December 19). “Lots and lots of labs have looked at how RNAs are changed by different environmental circumstances, but the RNA is only part of the story,” said Jenifer Coburn, a professor of medicine at Medical College of Wisconsin, who did not participate in the research. “This is something that’s really looking at the regulation of the production of the protein from the RNA, and that’s pretty new in Borrelia.”
News from ASCB
Researchers at this year's meeting of the American Society for Cell Biology (ASCB) discussed biophysics, funding woes, problems with peer review and research assessment, stem cells, and much more.
Enzyme Checks Neuronal Growth
A microtubule-severing enzyme curbs the regeneration of damaged nerve cells.
Cancer and Immune Cells Merge
Mouse colon cancer cells can fuse with macrophages, leading to changes in tumor growth.
Researchers link host glucose metabolism with severity of influenza infection.
Other news in life science:
CRISPR Creates Knockout Libraries
Two research groups have developed a database of human gene knockouts generated from the new genome editing technology.
Prove Antibacterials are Safe: FDA
The Food and Drug Administration is asking companies to produce evidence that their antimicrobial washes do no harm.
Examination of bones found in a Chinese village suggests that domesticated felines lived side-by-side with humans 5,300 years ago.
Researchers develop a nanobiopsy technique for sampling the contents of living cells.
Retinal Cells Printed by Inkjet
Scientists demonstrate how to print healthy rat retinal cells.