Copy number variation in neurons
WIKIMEDIA, GARPENHOLMGenomic analyses of single neurons revealed significant DNA copy number variation, researchers reported this week (October 31). Writing in Science, a team led by investigators at the Salk Institute for Biological Studies in La Jolla, California, also showed that neurons derived in culture from human induced pluripotent stem cells harbored similar copy number variations.
“It’s an exciting paper. It’s a closer look at the single cell genomes of neurons . . . and it identifies another layer of genomic mosaic changes that are occurring amongst neurons,” The Scripps Research Institute’s Jerold Chun, who was not involved in the work, told The Scientist.
Male hormone sparks mosquito egg production
WIKIMEDIA, JAMES D. GATHANYA steroid hormone passed from male to female during copulation stimulates the development of eggs in the mosquito Anopheles gambiae, scientists showed in PLOS Biology this week (October...
“[T]he paper provides insights into the complex biological cocktail that the male [mosquito] synthesizes to control the reproduction of the female he mates with,” mosquito physiologist Marc Klowden, a professor emeritus at the University of Idaho who was not involved in the research, told The Scientist.
The researchers suggested their findings could help inspire future reproduction-focused malaria control strategies, such as those targeting mating-induced oogenesis in A. gambiae.
Selectively spotting snakes
FLICKR, CHRISLIANG82By directly recording neuronal activity in the pulvinar, an area of the brain involved in visual processing, the University of California, Davis’s Lynne Isbell and her colleagues found evidence to suggest that certain neurons in the Japanese macaque (Macaca fuscata) respond selectively to images of snakes. These neuroscientific data supporting Isbell’s “snake detection theory” were published in the Proceedings of the National Academy of Sciences this week (October 28.)
“This is the first evidence of snake-selective neurons in the primate brain that I’m aware of,” said Seth Dobson, a biological anthropologist at Dartmouth College, who was not involved in the work. “And it provides some of the strongest support for the general idea that predation has been a major factor shaping primate evolution.”
“No Scrubs” for female spiders
MARIA ALBOBecause female Pisaura mirabilis spiders tend to retain sperm from suitors bearing nuptial gifts, males have plenty reason to provide for their mates. A team led by investigators at Aarhus University in Denmark recently showed in Proceedings of the Royal Society B: Biological Sciences that males who presented such gifts were more likely to successfully produce offspring.
“Cryptic female choice is notoriously difficult to demonstrate, but the authors did that by keeping other influences on sperm transfer constant,” Marie Herberstein, an associate professor at Australia’s Macquarie University who studies spider behavior but was not involved in the present study, told The Scientist.
Other news in life science:
Scientists Confirm Bats Carry SARS
Whole-genome sequences for two novel coronaviruses from Chinese horseshoe bats are the most closely related to the severe acute respiratory syndrome coronavirus to date.
One Big Family
Researchers use data from the anonymized profiles of a family history network to develop family trees including up to 13 million individuals.
A study shows that dendrites not only transmit information between neurons, but also process some of that information.
An academic-commercial partnership launches the largest cloud-based genomics project to date.
Gravity Determines Cell Size
Researchers show that cells may have evolved to be small because of gravitational forces.