Article abstract
Nature Cell Biology 2, 745 - 749 (2000)
Published online: 18 September 2000 | doi:10.1038/35036383
Schnurri mediates Dpp-dependent repression of brinker transcription
Thomas Marty1,3, Bruno Müller3,2, Konrad Basler3 & Markus Affolter1
Abstract
Signalling by Decapentaplegic (Dpp), a member of the TGF
superfamily
of signalling molecules, controls many aspects of Drosophila development
by activating and repressing target genes. Several essential components of
the Dpp signalling pathway have been identified, including the Dpp receptors
Punt and Thick veins (Tkv) as well as the cytoplasmic mediators Mad and Medea.
For target genes to be activated, Dpp signalling must suppress transcription
of a repressor encoded by the brinker (brk) gene. Here we show that
Schnurri (Shn), a large zinc-finger protein, is essential for Dpp-mediated
repression of brk transcription; in contrast, Shn is not required for
target-gene activation. Thus, the Dpp signalling pathway bifurcates, downstream
of the signal-mediating SMAD proteins, into a Shn-dependent pathway leading
to brk repression and a Shn-independent pathway leading to gene activation.
The existence of several Shn-like proteins in vertebrates and the observation
that Brk functions in BMP signalling in Xenopus indicates that a similar
regulatory cascade may be conserved in higher organisms.
- Abteilung Zellbiologie, Biozentrum, Universität Basel, Klingelbergstrasse 70, CH-4056 Basel, Switzerland.
- Institut für Molekularbiologie, Universität Zürich, Winterthurerstrasse 190, CH-8057 Zürich, Switzerland.
- These authors contributed equally to this work
Correspondence to: Markus Affolter1 e-mail: Markus.Affolter@unibas.ch
