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Repressing Gene Transcription by Redirecting Cellular Machinery with Chemical Epigenetic Modifiers
10:28

Repressing Gene Transcription by Redirecting Cellular Machinery with Chemical Epigenetic Modifiers

Published on: September 20, 2018

Osa-containing Brahma chromatin remodeling complexes are required for the repression of wingless target genes

R T Collins1, J E Treisman

  • 1Skirball Institute of Biomolecular Medicine and Department of Cell Biology, New York University School of Medicine, New York, New York 10016, USA.

Genes & Development
|December 22, 2000
PubMed

Insights

The trithorax group gene osa represses Wingless target genes in Drosophila development. Osa, part of the Brahma complex, alters chromatin structure to regulate gene expression, crucial for developmental processes.

Area of Science:

  • Developmental biology
  • Molecular genetics
  • Drosophila melanogaster research

Background:

  • The Wingless signaling pathway is crucial for numerous developmental processes in Drosophila.
  • This pathway regulates downstream target gene expression.

Purpose of the Study:

  • To investigate the role of the trithorax group gene osa in Wingless signaling.
  • To understand how Osa represses Wingless target genes in the absence of the Wingless signal.

Main Methods:

  • Analysis of osa mutants for gene misexpression.
  • Investigating the effect of ectopic Osa expression.
  • Examining Osa's function within the Brahma chromatin-remodeling complex.

Main Results:

  • Osa is required to repress Wingless target genes (nubbin, Distal-less, decapentaplegic, Ultrabithorax enhancer) in the absence of Wingless signal.
  • Osa-mediated repression occurs downstream of Armadillo up-regulation.
  • Osa functions as part of the Brahma chromatin-remodeling complex, which is essential for repressing Wingless target genes.

Conclusions:

  • Altering chromatin conformation is a key mechanism for Wingless signaling in gene activation.
  • The Brahma complex, including Osa, plays a vital role in repressing Wingless target genes.

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