Transposons in place of telomeric repeats at a Drosophila telomere

Cell. 1993 Dec 17;75(6):1083-93. doi: 10.1016/0092-8674(93)90318-k.

Abstract

We present the first isolation of the terminal DNA of an intact Drosophila telomere. It differs from those isolated from other eukaryotes by the lack of short tandem repeats at the terminus. The terminal 14.5 kb is composed of four tandem elements derived from two families of non-long terminal repeat retrotransposons and is subject to slow terminal loss. One of these transposon families, TART (telomere-associated retrotransposon), is described for the first time here. The other element, HeT-A, has previously been shown to transpose to broken chromosome ends. Our results provide key evidence that these elements also transpose to natural chromosome ends. We propose that the telomere-associated repetitive DNA is maintained by saltatory expansions, including terminal transpositions of specialized retrotransposons, which serve to balance terminal loss.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Base Sequence
  • Chromosome Mapping
  • Cloning, Molecular
  • DNA / chemistry*
  • DNA / genetics
  • DNA / isolation & purification
  • DNA Transposable Elements*
  • Drosophila / genetics*
  • Drosophila melanogaster / genetics*
  • In Situ Hybridization
  • Molecular Sequence Data
  • Open Reading Frames
  • Repetitive Sequences, Nucleic Acid*
  • Retroviridae
  • Salivary Glands / cytology
  • Salivary Glands / metabolism
  • Species Specificity
  • Telomere / physiology*
  • Telomere / ultrastructure

Substances

  • DNA Transposable Elements
  • DNA

Associated data

  • GENBANK/U02279