Why do blind mole rats enjoy a very long life?
"Retrotransposons are DNA sequences that can move about the genome by copying themselves from their RNA transcripts and reinserting into new locations. Also known as jumping genes, these DNA elements, which may be the remnants of ancient viral infections, are generally thought to provide little or no benefit to the host and can even cause harmful mutations. However, blind mole rats (Spalax spp.) use these pieces ... to protect itself from cancer, reports a study in Nature Immunology last week (September 23)—a discovery that experts say may have implications for human treatments. ...
Blind mole rats are small, furry, subterranean rodents that can live up to 20 years—roughly 10 times as long as a similarly sized mouse. This unusual longevity is explained in part by the animal’s natural resistance to cancer, mediated by the widespread initiation of cell death among rapidly proliferating precancerous cells. The cell death is triggered by increased production of the inflammatory cytokine interferon beta (IFN-β), but what causes IFN-β to ramp-up was unknown. ...
“It’s a little bit counterintuitive because we’ve learnt a lot about why mammals and other species like to keep retrotransposons inactive,” ..., but blind mole rats have “actually leveraged [retrotransposons] for their benefit—to eliminate the premalignant cells and prevent cancer transformation.” ..."
Blind mole rats are small, furry, subterranean rodents that can live up to 20 years—roughly 10 times as long as a similarly sized mouse. This unusual longevity is explained in part by the animal’s natural resistance to cancer, mediated by the widespread initiation of cell death among rapidly proliferating precancerous cells. The cell death is triggered by increased production of the inflammatory cytokine interferon beta (IFN-β), but what causes IFN-β to ramp-up was unknown. ...
“It’s a little bit counterintuitive because we’ve learnt a lot about why mammals and other species like to keep retrotransposons inactive,” ..., but blind mole rats have “actually leveraged [retrotransposons] for their benefit—to eliminate the premalignant cells and prevent cancer transformation.” ..."
From the abstract:
"Blind mole rats (BMRs) are small rodents, characterized by an exceptionally long lifespan (>21 years) and resistance to both spontaneous and induced tumorigenesis. Here we report that cancer resistance in the BMR is mediated by retrotransposable elements (RTEs). Cells and tissues of BMRs express very low levels of DNA methyltransferase. Following cell hyperplasia, the BMR genome DNA loses methylation, resulting in the activation of RTEs. Upregulated RTEs form cytoplasmic RNA–DNA hybrids, which activate the cGAS–STING pathway to induce cell death. ..."
No comments:
Post a Comment