The male proboscis monkey’s large nose probably evolved in response to female preference and competition between males.
Chilly mice develop more tumors; gut bacteria aid cancer treatment; two Y chromosome genes sufficient for assisted reproduction; HIV’s “invisibility cloak”
November 22, 2013|
KATHLEEN KOKOLUS AND ELIZABETH REPASKYMice housed in laboratories beneath their natural body temperature of 30°C or 31°C are less able to fend off tumors than animals kept in warmer rooms. Roswell Park Cancer Institute’s Elizabeth Repasky and her colleagues found that compared with their counterparts housed at a comfortable temperature for humans—between 20°C and 26°C—mice injected with tumor cells and kept at 30°C to 31°C showed reduced tumor formation and metastasis, effects mediated by the adaptive immune system. Their work was published this week (November 18) in Proceedings of the National Academy of Sciences.
“It’s one of the things that’s under everybody’s nose, and nobody really thought about it much,” Duke University’s Mark Dewhirst, who was not involved in the work, told The Scientist. “Everybody thought that mice would be fine at room temperature, but nobody ever thought to look.”
WIKIMEDIA, NCIBacteria lining the guts of mice help animals being treated for cancerous tumors by triggering inflammatory and immune system responses. Germ-free or antibiotic-treated mice fared worse than their microbe-laden counterparts, according to two independent studies out this week (November 21) in Science, led by researchers at INSERM in France and the National Cancer Institute.
“Most of the time we think about the gut microbiome shaping the local environment. Now these papers are breaking the glass ceiling and going into extra-intestinal organs . . . and influencing activities of drugs,” said Christian Jobin from the University of Florida, who reviewed both studies but was not involved in either.
“Both studies are very exciting in that they show initial links between gut microbiota and [response to] therapies,” agreed Harvard University’s Peter Turnbaugh, who was not involved in the investigations. The papers, he added, “underscore the importance [of] microbes in shaping not just our initial predisposition to disease, but also our recovery from it.”
MONIKA WARDTwo Y chromosome genes are the only contribution needed from the male chromosome for male mice to father offspring, according to a paper published in Science this week (November 21). University of Hawaii’s Monika Ward and her colleagues showed that male mice lacking a Y chromosome but carrying the Y-linked genes Sry and Eif2s3y could produce spermatids that, when introduced to female eggs via round spermatid injection, resulted in embryos that could be transplanted into the oviducts of recipient females to produce live offspring.
“It’s quite an amazing technique to be able to get live, healthy offspring from round spermatids,” said Polly Campbell from Oklahoma State University, who was not involved in the work.
The researchers stressed, however, that the remaining Y genes are still important to support normal male fertility.
WIKIMEDIA, FLYING PUFFINBacteria can usurp small, damaged fragments of DNA, including those from a 43,000-year-old woolly mammoth, according to study published this week (November 18) in Proceedings of the National Academy of Sciences.
Fragments of degraded DNA are abundant in the environment, “and if [they] can be used for transformation or mutagenesis, that suggests [they play] a much larger evolution-driving role than previously ever realized,” said Northwestern University’s Hank Seifert, who was not involved in the study.
Lead author Søren Overballe-Petersen from the University of Copenhagen told The Scientist that the process is akin to rummaging through the garbage can. Sometimes the bacteria will get cut by a piece of broken glass, but “once in a while, you’ll strike gold,” he said.
WIKIMEDIA, NIHThe capsid protein that makes up HIV-1’s outer coat helps the virus evade immune detection, researchers from the Institut Curie in Paris have found. Their work was published in Immunity this week (November 21).
“By playing with the capsid, we made an HIV-1 that does not replicate but can stimulate an immune response,” lead author Nicolas Manel told The Scientist. “We could imagine modifying the virus and using it as a vaccine.”
“We used to think that the capsid came off the virus when it entered the cell, and its job was done. It turns out that it also protects the virus’s DNA from being seen,” said Greg Towers from University College London, who was not involved in the work.
Two-time Nobel Laureate Dies
Frederick Sanger, who pioneered amino acid and DNA sequencing techniques, has passed away at age 95.
Conflicting clinical trial results leave researchers unsure whether genetic information is useful for determining initial Warfarin dosage.
Ancient Genomes Reveal Secrets
New Neanderthal and Denisovan genomes point to the existence of an unidentified early human.
Lab-Grown Kidney Buds
Using human stem cells, investigators from the U.S. and Spain generate functional ureteric buds.
Public View of Science in EU
A new public opinion poll shows European Union citizens feel favorably about science and technology, but in the dark about advances in the fields.