WIKIMEDIA, CARL DAVIES, CSIROCompared to humans’ century-long life span, some plants—evergreens in particular—have the capacity to live for an exceptionally long time, even millennia. In a study published in Current Biology today (May 5), scientists from the University of Bern in Switzerland present evidence for a potential mechanism that could help explain some plants’ everlasting longevity: minimal stem cell divisions to avoid “mutational meltdown.”
The team zeroed in the formation of axillary meristems—stem cells that give rise to branches—in Arabidopsis thaliana and tomato, finding few cell divisions between the apical meristem located at the very top of a plant and the axillary meristems. With such little proliferation comes less opportunity to accumulate potentially deleterious genetic mutations in somatic cells that could kill the organism, the authors reasoned.
“Meristem aging is not a problem for perennial plants, in other words,” said Sergi Munné Bosch, a plant physiologist at the University of Barcelona who was not part of the study. “The meristems are the growing units. If they don’t senesce, then the plant will keep the capacity to grow and reproduce forever, at least potentially.” Instead, he added, structural defects or ...
