Age at maturation has sex- and temperature-specific effects on telomere length in a fish

Abstract

Telomeres are highly conserved nucleoprotein structures which protect genome integrity. The length of telomeres is influenced by both genetic and environmental factors, but relatively little is known about how different hereditary and environmental factors interact in determining telomere length. We manipulated growth rates and timing of maturation by exposing full-sib nine-spined sticklebacks (Pungitius pungitius) to two different temperature treatments and quantified the effects of temperature treatments, sex, timing of maturation, growth rate and family (genetic influences) on telomere length. We did not find the overall effect of temperature treatment on the relative telomere length. However, we found that variation in telomere length was related to timing of maturation in a sex- and temperature-dependent manner. Telomere length was negatively related to age at maturation in elevated temperature and early maturing males and females differed in telomere length. Variation in growth rate did not explain any variation in telomere length. The broad sense heritability (h ) of telomere length was estimated at h = 0.31 - 0.47, suggesting predominance of environmental over genetic determinants of telomere length variability. This study provides the first evidence that age at maturation together with factors associated with it are influencing telomere length in an ectotherm. Future studies are encouraged to identify the extent to which these results can be replicated in other ectotherms.

Carry‐over effects of early thermal conditions on somatic and germline oxidative damages are mediated by compensatory growth in sticklebacks

“…Telomere length was measured in muscle and sperm DNA samples (see above) by using the qPCR method developed by Cawthon (2002) and recently validated in another stickleback species (Noreikiene, Kuparinen, & Merilä, 2017). The relative telomere length of each sample was measured by determining the ratio (T/S) of telomere repeat copy number (T) to single control gene copy number (S), relative to a reference sample.…”

Early Biological Aging and Fetal Exposure to High and Low Ambient Temperature: A Birth Cohort Study

“…However, animal-based studies using different fish species indicate a negative association between temperature and TL (Debes et al. 2016; Noreikiene et al. 2017; Simide et al.…”

Environment‐induced changes in reproductive strategies and their transgenerational effects in the three‐spined stickleback

“…Importantly, although carotenoids are involved in important physiological processes for somatic maintenance, such as antioxidant protection (Pike et al, 2007), the increase of carotenoid-based coloration did not affect telomere loss in the late males. Our results show that the environment experienced by male and female breeders before their reproduction can have different effects on telomere dynamics (see also Noreikiene et al, 2017). However, it is also possible that we could not detect the interacting effect of the treatment and reproductive effort on telomere dynamics of males, because the males were not allowed to perform costly parental care (i.e., fanning behavior for aerating eggs in the nest) in our experiment.…”