His decision came as an investigation into sexual harassment allegations against him was ongoing.
Genomic analysis of an oak tree that lived during Napoleon’s time supports the idea that plants somehow avoid the accumulation of mutations in their stem cells.
June 20, 2017|
Sequencing DNA collected from leaves on different branches of a 234-year-old oak tree on the University of Lausanne campus in Switzerland, plant biologist Philippe Reymond and colleagues found far fewer single base-pair substitutions than expected based on known plant mutations rates and the number of cell divisions that presumed to have occurred between an old branch near the tree’s base and a younger branch 40 meters higher up. The team, which did not analyze other types of genetic mutations such as deletions, published its results last week (June 13) on the preprint server bioRxiv.
“It’s a tantalizing study,” Daniel Schoen, a plant evolutionary biologist at McGill University in Montreal, Canada, tells Nature. “It touches on something that was simmering always, in the back of the minds of plant biologists.”
Specifically, the findings support the idea that plants somehow protect their stem cells from accumulating mutations. Last year, for example, scientists from the University of Bern found evidence in Arabidopsis thaliana and tomato that plants limit the number of cell divisions in the meristem tissues that house the stem cells that support plant growth. “Plants seem to set aside some cells in such a way as to minimize the number of mutations they accumulate,” Rob Lanfear of Macquarie University in Australia wrote in an email to The Scientist following the study’s publication.
June 21, 2017
Now how about some of the really ancient plants, like some Australian mallees,
or American bristle-cone pines...
We are living in a golden age of conceptual advances in biology and in particular in molecular biology; we must guard against increasingly dangerous tendencies to become blase. The trickle of discoveries beyond our dreams fifty years ago has become a flood. It is harder and harder to maintain perspective, and to construct new perspectives as increasing functional complexities emerge.