aubergine mutations in Drosophila melanogaster impair P cytotype determination by telomeric P elements inserted in heterochromatin

Mol Genet Genomics. 2004 Oct;272(3):336-43. doi: 10.1007/s00438-004-1061-1. Epub 2004 Sep 14.

Abstract

Transposable P elements inserted in the heterochromatic Telomeric Associated Sequences on the X chromosome (1A site) of Drosophila melanogaster have a very strong capacity to elicit the P cytotype, a maternally transmitted condition which represses P element transposition and P-induced hybrid dysgenesis. This repressive capacity has previously been shown to be sensitive to mutant alleles of the gene Su(var)205, which encodes HP1 (Heterochromatin Protein 1), thus suggesting a role for chromatin structure in repression. Since an interaction between heterochromatin formation and RNA interference has been reported in various organisms, we tested the effect of mutant alleles of aubergine, a gene that has been shown to play a role in RNA interference in Drosophila, on the repressive properties of telomeric P elements. Seven out of the eight mutant alleles tested clearly impaired the repressive capacities of the two independent telomeric P insertions at 1A analyzed. P repression by P strains whose repressive capacities are not linked to the presence of P copies at 1A were previously found to be insensitive to Su(var)205; here, we show that they are also insensitive to aubergine mutations. These results strongly suggest that both RNA interference and heterochromatin structure are involved in the establishment of the P cytotype elicited by telomeric P elements, and reinforce the hypothesis that different mechanisms for repression of P elements exist which depend on the chromosomal location of the regulatory copies of P.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Animals
  • Drosophila Proteins / genetics*
  • Drosophila melanogaster / genetics*
  • Female
  • Gonadal Dysgenesis
  • Heterochromatin / genetics*
  • Male
  • Mutation*
  • Peptide Initiation Factors / genetics*
  • RNA Interference
  • Telomere*

Substances

  • Drosophila Proteins
  • Heterochromatin
  • Peptide Initiation Factors
  • aub protein, Drosophila