Bats are some of the longest-lived mammals in the world relative to their size. Professor Emma Teeling and her team studied bat telomeres, the caps at the end of chromosomes, in search of longevity mechanisms. In a paper published this year, she showed that long-lived bats might be able to repair damage to their DNA to live longer, healthier — while also avoiding cancer.
The Relationship Between Telomeres and Longevity
The end of every pair of chromosomes is capped by a telomere, a repetitive string of nucleotides that serves like the bumper of a car: As cells divide, its sections are lost, protecting the more important blueprint of DNA information inside. For some time, biologists have theorized a connection in some animals between telomere length and longevity, because when telomeres become too short, cells become senescent. But the inverse also causes problems: Telomerase, an enzyme that re-lengthens telomeres, is associated with cancer, since it allows cells — including cancerous ones — to reproduce at will.
In bats, which rarely get cancer and are some of the longest-lived mammals relative to their size, the connection between longevity and telomere length was not well known. Along with 10 different international teams across Europe, Emma Teeling of University College Dublin used wing samples from four different species of long-lived bats and measured telomere length and telomerase expression to reveal differences in mechanisms that seem to be the reason they live such long lives. Would these long-lived bats experience shortening of the telomeres, like many other mammals, or did they have a mechanism that could maintain telomere length but not cause cancer?
Key Findings: Some Bats Have Alternative DNA Repair Mechanisms for Telomeres . In two species, telomeres did shorten with age — an unextraordinary result. But in the two other species of bats, both of the myotis family, telomeres did not shorten with age. But Teeling and her colleagues also could not find any evidence of telomerase production, the traditional method used by mammals to maintain telomere length. (This squared with the lack of cancer found in bats; animals like mice that use telomerase have high incidences of cancer.) Instead, researchers found evidence that the two species of myotis bats were maintaining telomere length in an alternative way, with two genes that boost DNA repair mechanisms that may in turn maintain or repair the telomeres.
Teeling believes this is a potent longevity mechanism, but also that the difference in telomere maintenance among bat species shows there are multiple pathways to longevity in play.
provided by Endpoints.