Principal Investigator Mary-Lou Pardue
The telomeric retrotransposons are non-LTR (non-Long Terminal Repeat) retrotransposons, closely related to a clade of non-LTR retrotransposons that are abundant in non-telomeric chromosome regions in Drosophila and other insects. However the telomere elements have features not seen in the related non-telomeric elements. To investigate the importance of these features for telomere biology, we have isolated telomere-specific elements from distantly related Drosophila. We were able to find that HeT-A and TART form telomeres in D. virilis (40-60 My [million years] separated from the archetypical D. melanogaster). This mechanism of telomere maintenance must predate the separation of these, most distantly related, Drosphila species. HeT-A and TART appear to cooperate, rather than compete, at telomeres. All D. melanogaster stocks and Drosophila species studied have both elements. (TAHRE, closely related toHeT-A, is very rare and may not be present in all species.) In spite of extreme sequence divergence of the telomere elements, the unique features of the Drosophila telomere retrotransposons have been conserved in all species studied and are apparently related to their roles in telomeres.