P13-7 Sat Jan 2 Regeneration in Lumbriculus variegatus entails differential expression of telomerase reverse transcriptase Fischer, F*; LaRocca-Stravalle, Z; Gillen, K; Kenyon College; Kenyon College; Kenyon College gillenk@kenyon.edu https://works.bepress.com/kathy_gillen/
Functional telomeres are required for genomic stability and continued cell proliferation. Increased expression of telomerase reverse transcriptase (tert), the catalytic subunit of the telomerase holoenzyme, helps prevent cellular senescence and maintains proliferative capacity in mitotic cells, while low expression parallels cell differentiation. Despite the importance of telomerase for cellular processes necessary for tissue regeneration, few studies have examined tert expression in annelids. Lumbriculus variegatus (Annelida, Oligochaeta) regenerates bidirectionally following transverse amputation or asexual fission, and also displays continuous posterior growth that is independent of regeneration. We examined tert expression in L. variegatus to further investigate the role of telomerase during regeneration. Tert was expressed constitutively in intact worms, which may indicate the presence of self-renewing stem and/or germ cells that participate in normal growth. Upregulation of tert in segments undergoing extensive cell proliferation associated with epimorphic regeneration implies that tert may function to maintain proliferative capability in mitotic cells. Interestingly, tert was downregulated early during the regenerative process (24 hours post-amputation). As decreased tert expression is often associated with cell differentiation and apoptosis, it is tempting to hypothesize that modulation of tert expression may play a role in wound healing or regeneration. In the future, we plan to examine telomerase protein activity using the TRAP assay and analyze global transcriptional changes via transcriptomics.