The Groucho/Transducin-like enhancer of split protein family in animal development

Abstract

Corepressors are proteins that cannot bind DNA directly but repress transcription by interacting with partner proteins. The Groucho/Transducin-Like Enhancer of Split (TLE) are a conserved family of corepressor proteins present in animals ranging from invertebrates such as Drosophila to vertebrates such as mice and humans. Groucho/TLE proteins perform important functions throughout the life span of animals, interacting with several pathways and regulating fundamental processes such as metabolism. However, these proteins have especially crucial functions in animal development, where they are required in multiple tissues in a temporally regulated manner. In this review, we summarize the functions of the Groucho/TLE proteins during animal development, emphasizing on specific tissues where they play essential roles.

Keywords: corepressor; development; groucho; homeobox genes; transcription factor; transducin-like enhancer of split (TLE).

Fig 1

Domain architecture of Groucho/TLE family proteins. The domain architecture of mouse TLE1 is shown as a typical example of the Groucho/TLE family of proteins. The TLE N-terminal domain, also known as the Q-rich domain is essential for transcription factor binding and oligomerization (brown). The central region is relatively less conserved across evolution (green), whereas the C-terminal WD40 repeats are important for transcription factor binding and repression (red). The WD40 repeat domain is the most conserved part of Groucho/TLE and related families of corepressors across evolution. The structure of the WD40 repeat domain has been elucidated in the case of human TLE1 and forms a β-propeller with seven blades and a central pore, with the central pore facilitating interactions with peptide motifs such as WRPW and Eh1 in interacting proteins.