Meeting Abstract
Telomeres are conserved DNA sequences that serve as protective caps for linear DNA. Over time, telomeres degrade due to factors including the end-replication problem and oxidative stress. Once telomeres reach a critical length, they initiate a cell signalling pathway resulting in cellular senescence, a hallmark of aging. While telomeres are well-studied in the context of senescence at a cellular level, the relationship between telomeres and organismal longevity is less understood, as most studies focus on within species rather than across species phenomena. Here, we use cross-sectional telomere data from nineteen species to investigate four recent hypotheses in the telomere biology literature: (i) whether the maximum lifespan of a species is associated with either the mean telomere length of that species, or (ii) the telomere loss rates of that species, (iii) whether short telomeres and fast attrition rates play a causal role in aging, as suggested by the telomeric brink hypothesis, and (iv) whether long telomeres are more subject to damage-induced shortening compared to short telomeres. We found that in birds telomere shortening rates (ii), but not mean telomere length (i) relates to species maximum lifespan. In addition, we find no support for the telomeric brink hypothesis (iii) or that longer telomeres are more subject to shortening compared to short telomeres (iv). Our study highlights that comparative data sets can provide powerful insight into the relationship between telomere biology and organismal longevity.
