The shortening of telomeres in cells was thought to be an important biomarker for lifespan and aging. The edible dormouse (Glis glis), a small hibernating rodent, now turns everything upside down. In contrast to humans and other animals, telomere length in the edible dormouse significantly increases in the second half of its life, as researchers from Vetmeduni Vienna found out just recently.
The study was published in Scientific Reports.
“As far as I know, no previous study has reported such an effect of age on telomere lengthening,” says Franz Hoelzl, one of the authors. Apparently, this unique pattern is due to the peculiar life history of this species. They can reach maximum lifespan of 13 years, which is a Methuselah-like age for a small rodent. “This extreme lifespan is almost certainly related to their ability to rejuvenate telomeres”, says Hoelzl. Telomeres are the endcaps of chromosomes, which prevent, together with proteins, the degradation of coding DNA sequences.
Telomeres in small animals shorten fast, but in edible dormice they even grow
In normal somatic cells, telomeres are shortened with every cell division. Besides, oxidative stress has a strong effect on telomere erosion. However, the rate of telomere shortening differs between species. For instance, it has been shown before that telomeres in fast-aging, short-lived wild animals erode more rapidly than in slow-aging, long-lived species.
Earlier this year, the author Franz Hoelzl and his colleagues from Vetmeduni Vienna showed that edible dormice has the capability to re-elongated its telomeres, given that food availability is high. This finding raised the question about the long-term balance between telomere attrition and repair.
The relative telomere length (RTL) gave evidence
To find an answer, the team started a long-tem study on changes in telomere length. In the Vienna Woods in Austria they regularly checked 130 nest-boxes that are occupied by free-living dormice. The researchers collected the rodent’s buccal mucosa for three years. Thus, they could extract the DNA and determine the relative telomere length for each dormouse individually using qPCR. With this method scientists can define the amount of target DNA compared to a reference gene of the same sample.
Elongation does not only occur, it even increases in older edible dormice
“We found out that the telomeres were shortened in young animals but length significantly increased once the dormice were six years old or older. To top it all, the rate of telomere elongation also increased with increasing age of the dormice”, says Franz Hoelzl.
Among the variables tested, only age significantly affected RTL in a non-linear pattern with telomere length decreasing in younger and increasing in older dormice. Hoelz says, “Telomere length was not affected by time of the year, sex, body mass or reproductive activity at the time of sampling.” Nevertheless, the analysis of long term reproduction-data of the same population shows that the probability to reproduce also increases with age. This finding could indicate that telomere elongation is actually part of the preparation for upcoming reproductive events, as gestation and lactation could increase oxidative stress and the animals may attempt to protect their genome.
The Latest on: Telomeres
via Google News
The Latest on: Telomeres
- How human food is changing wildlife on February 21, 2019 at 8:44 am
Researchers discovered changes in their DNA; namely, a signature loss of the caps (called telomeres) on the ends of their chromosomes. These caps naturally shorten as animals age. It is one of the sub... […]
- Titia de Lange to give annual McCormick Lecture on March 8 on February 20, 2019 at 4:35 pm
McCormick Distinguished Lecture at 4 p.m. March 8 at the Li Ka Shing Center for Learning and Knowledge. The title of her talk is “Telomeres and the DNA damage response.” The event is free and open to ... […]
- Danazol Treatment for Telomere Diseases on February 18, 2019 at 5:10 pm
Telomeres are repeated hexanucleotides and associated proteins that are located at the ends of linear chromosomes; telomeres function to protect the chromosome ends from recognition as damaged or infe... […]
- Telomeres and telomerase: three decades of progress on February 13, 2019 at 11:25 am
Many recent advances have emerged in the telomere and telomerase fields. This Timeline article highlights the key advances that have expanded our views on the mechanistic underpinnings of telomeres an... […]
- A subtelomeric region affects telomerase-negative replicative senescence in Saccharomyces cerevisiae on February 12, 2019 at 2:53 am
In eukaryotes, telomeres determine cell proliferation potential by triggering replicative senescence in the absence of telomerase. In Saccharomyces cerevisiae, senescence is mainly dictated by the fir... […]
- Father Loss Associated With Shorter Telomeres in Nine-Year-Old Children on July 5, 2018 at 4:03 am
A new study has found a link between loss of a father—through death, imprisonment or parental separation—and reduced telomere length. Telomeres are repetitive DNA sequences at the ends of chromosomes. ... […]
- The fission yeast Stn1-Ten1 complex limits telomerase activity via its SUMO-interacting motif and promotes telomeres replication on May 16, 2018 at 11:11 am
1 CRCM, CNRS, INSERM, Aix-Marseille Université, Institut Paoli-Calmettes, Equipe Labellisée Ligue, 27 Boulevard Lei Roure, Marseille, France. 2 Telomere and Genome Stability Laboratory, Instituto Gulb... […]
- What in the world are telomeres and why do they matter? on April 9, 2018 at 12:39 pm
This year’s winner of the prestigious Lewis S. Rosenstiel Award for Distinguished Work in Basic Medical Research, scientist Titia de Lange, will officially receive the honor on Thursday, April 12 and ... […]
- Scientists Found a Way to Stop Aging in Human Cells on July 31, 2017 at 11:58 am
The paper notes that 12 of the 17 participants in this study (aged one to 14 years) had shortened telomeres, similar to what would ... Get six of our favorite Motherboard stories every day by signing ... […]
via Bing News