Control of Telomere Length in Drosophila

The problem of incomplete end replication of DNA was originally raised by the Russian scientist Aleksey Olovnikov (Olovnikov, 1971, 1973). The main function of telomeric DNA is the compensation of end degradation. In most eukaryotes, telomeric DNA is maintained by the action of telomerase, which is responsible for the synthesis of short 6-9 nucleotide repeats using an RNA component as a template (Greider and Blackburn, 1985). In contrast, telomeres of Drosophila are maintained as a result of retrotransposition of specialized telomeric non-long terminal repeat retrotransposons (Biessmann et al., 1990a; Biessmann et al., 1992a; Levis et al., 1993; Abad et al., 2004b).