Crosstalk between the EGFR and other signalling pathways at the level of the global transcriptional corepressor Groucho/TLE

Abstract

In this minireview, we briefly revisit the Drosophila Notch and epidermal growth factor receptor pathways, and relate to the relationship between them. We then mainly focus on the involvement of Groucho (Gro)/TLE, a global developmental corepressor, in these pathways. In particular, we discuss Gro/TLE's role at the junction between these two signal transduction cascades.

Figure 1

EGFR signalling leads to the formation of wing veins by overriding Groucho-mediated repression. (A) Shown are abbreviated presentations of the EGFR and Notch signalling pathways. (B) A photograph of a Drosophila wing, with the veins numbered (L1–L5). Below, a schematic illustration of adjacent vein and intervein regions, depicting how MAPK phosphorylation of Gro may relieve transcriptional silencing by multiple antivein Gro-dependent repressors, promoting the formation of wing veins.

Figure 2

Attenuation of Groucho-mediated repression by RTK signalling: possible implications. (A) Coordinated derepression of a large array of genes. (B) Switching between modes of transcriptional regulation. (C) Groucho integrates RTK signaling with multiple pathways.