Initiation of dosage compensation in Drosophila embryos depends on expression of the roX RNAs

Mech Dev. 2003 Jul;120(7):759-67. doi: 10.1016/s0925-4773(03)00157-6.


The roX1 and roX2 genes of Drosophila produce non-coding transcripts that localize to the X-chromosome. In spite of their lack of sequence similarity, they are redundant components of an RNA/protein complex that up-regulates the male X-chromosome, contributing to the equalization of X-linked gene expression between males and females. roX1 is detected at 2 h AEL, prior to formation of the complex, and is present in both sexes. Maternally provided MLE (Maleless) is required for roX1 stability. By contrast, roX2 is male-specific and is first observed at 6 h. Either roX transcript can support X-localization of the complex, but localization is delayed in roX1 mutants until roX2 expression. These results support a model for the ordered assembly of the complex in embryos.

Publication types

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

MeSH terms

  • Animals
  • Dosage Compensation, Genetic*
  • Drosophila / embryology
  • Drosophila / genetics
  • Drosophila Proteins / genetics*
  • Drosophila Proteins / metabolism
  • Female
  • Male
  • RNA, Messenger / metabolism
  • RNA-Binding Proteins / genetics*
  • RNA-Binding Proteins / metabolism
  • Time Factors
  • Transcription Factors / genetics*
  • Transcription Factors / metabolism


  • Drosophila Proteins
  • Pabp2 protein, Drosophila
  • RNA, Messenger
  • RNA-Binding Proteins
  • Transcription Factors
  • roX1 protein, Drosophila