Abstracts (first author)
Ageing as a trade-off mechanism: what telomeres actually tell us?PDF
Telomeres are chromosome ends that protect the cell’s genomic integrity. Telomeres are lost at a variable rate as a result of the imbalance between pro- (oxidative stress) and anti-erosion processes (telomerase), and once critically shortened, telomeres can trigger cell death (apoptosis). Consequently telomere function has been one of the main cell mechanisms studied in ageing biology. Recently, it has been proposed that telomeres might be critical for our understanding of life-history trade-offs in general. Telomere length is heritable and at the organism level telomere length has been shown to correlate with individual longevity, first in humans but also in wild animals, appearing as a strong proxy of individual survival. Furthermore, telomere length was recently proposed to reflect individual phenotypic quality in terms of high rates of reproduction. All these studies suggest that telomere dynamics may be one of the key genetic determinants explaining the individual variability in ageing and fitness. However, the nature of the determinants leading to changes in telomere length early in life, during development, and of the mechanisms that link telomere length to fitness remain unknown. In this talk, I will present some of the data collected by our group which is studying how telomere length may be implicated in life-history trade-offs. For this I will show how an experimental manipulation of the cost of reproduction in zebra finch may affect telomere loss of breeders, but also how this brood size manipulation has affected telomere length in chicks. In a second step, I will show how telomere lengths are varying in early life in two wild species, great and coal tits, and how these variations may be link to local adaptation to favour chick growth and survival. Finally, as a short perspective, results of a pilot study on telomerase activity will propose a hypothetical pathway by which telomere biology may influence individual fitness.