The attrition of telomeres, the ends of eukaryote chromosomes, and activity of telomerase, the enzyme that restores telomere length, play a role in the ageing process and act as indicators of biological age. A notable feature of advanced eusocial insects is the longevity of reproductive individuals (queens and kings) compared to those from non-reproductive castes (workers and soldiers) within a given species, with a proposed link towards upregulation of telomerase activity in the somatic tissues of reproductive individuals. Given this, eusocial insects provide excellent model systems for research into ageing. We tested telomerase activity and measured telomere length in Bombus terrestris, which is a primitively eusocial insect species with several distinct features compared to advanced social insects. In somatic tissues, telomerase activity was upregulated only in the fat bodies of pre-diapause queens, and this upregulation was linked to heightened DNA synthesis. Telomere length was shorter in old queens compared to that in younger queens or workers. We speculate that (1) the upregulation of telomerase activity, together with DNA synthesis, is the essential step for intensifying metabolic activity in the fat body to build up a sufficient energy reserve prior to diapause, and that (2) the lifespan differences between B. terrestris workers and queens are related to the long diapause period of the queen. A possible relationship between telomere length regulation and TOR, FOXO, and InR as cell signaling components, was tested.

Biology Centre of the Czech Academy of Sciences Institute of Entomology Branišovská 31 370 05 České Budějovice Czech Republic

Biology Centre of the Czech Academy of Sciences Institute of Entomology Branišovská 31 370 05 České Budějovice Czech Republic; Faculty of Pedagogy University of South Bohemia Branišovská 31 370 05 České Budějovice Czech Republic

Biology Centre of the Czech Academy of Sciences Institute of Entomology Branišovská 31 370 05 České Budějovice Czech Republic; Faculty of Science University of South Bohemia Branišovská 31 370 05 České Budějovice Czech Republic

Koppert s r o Komárňanská cesta 13 940 01 Nové Zámky Slovakia

References provided by Crossref.org

Extended longevity of termite kings and queens is accompanied by extranuclear localization of telomerase in somatic organs and caste-specific expression of its isoforms

Telomeres and telomerase: active but complex players in life-history decisions

The rate of DNA synthesis in ovaries, fat body cells, and pericardial cells of the bumblebee (Bombus terrestris) depends on the stage of ovarian maturation

Telomerase RNA in Hymenoptera (Insecta) switched to plant/ciliate-like biogenesis

Telomeric DNA sequences in beetle taxa vary with species richness

Long-lived termite kings and queens activate telomerase in somatic organs

Seasonality in telomerase activity in relation to cell size, DNA replication, and nutrients in the fat body of Apis mellifera