Conversion of Dorsal from an activator to a repressor by the global corepressor Groucho (original) (raw)

1. Todd Dubnicoff1,4,5,
2. Scott A. Valentine1,
3. Guoqing Chen1,
4. Tao Shi1,
5. Judith A. Lengyel2,4,
6. Ze’ev Paroush3, and
7. Albert J. Courey1,4,6
8. 1Department of Chemistry and Biochemistry,2Department of Molecular, Cell, and Developmental Biology,4Molecular Biology Institute, University of California at Los Angeles, Los Angeles, California 90095 USA; 3Department of Biochemistry, The Hebrew University—Hadassah Medical School, Jerusalem 91120, Israel

Abstract

The Dorsal morphogen acts as both an activator and a repressor of transcription in the Drosophila embryo to regulate the expression of dorsal/ventral patterning genes. Circumstantial evidence has suggested that Dorsal is an intrinsic activator and that additional factors (corepressors) convert it into a repressor. These corepressors, however, have previously eluded definitive identification. We show here, via the analysis of embryos lacking the maternally encoded Groucho corepressor and via protein-binding assays, that recruitment of Groucho to the template by protein:protein interactions is required for the conversion of Dorsal from an activator to a repressor. Groucho is therefore a critical component of the dorsal/ventral patterning system.

• dorsal
• groucho
• corepressor
• Drosophila
• pattern formation
• embryogenesis

Footnotes

• ↵5 Present address: Tularik, Inc., South San Francisco, California 94080, USA.

• ↵6 Corresponding author.

• E-MAIL courey{at}chem.ucla.edu; FAX (310) 206-4038.

• • Received August 26, 1997.
  • Accepted September 4, 1997.

• Cold Spring Harbor Laboratory Press

•