<p>The Groucho (Gro)/transducin-like enhancers (TLE) are a family ofevolutionarily conserved corepressor proteins that play a critical role indiverse developmental and cellular pathways, including lateral inhibition,segmentation, sex determination, dorsal/ventral pattern formation, terminalpattern formation, and eye development [<cite idref="PUB00013901"/>]. </p><p>The Gro/TLE family contain two highly conserved domains, a C-terminalWD-repeat domain and an N-terminal glutamine rich (Q) domain, in additionto a variable central region. The highly conserved Q domains are unique tothe Gro/TLE family and are not found in other WD-repeat proteins. Thevariable region contains a loosely conserved CcN motif, consisting of putative cdc2 kinase (cdc2) and casein kinase II (CKII) phosphorylation sites, as well as a nuclear localisation signal [<cite idref="PUB00013902"/>]. The CcN motif is flanked by two poorly conserved regions, which are characteristically rich in either glycine and proline or serine and proline residues, GP and SP domains respectively.</p><p>Gro/TLE family proteins do not bind to DNA directly as they lack anyDNA-binding domain. However, they are recruited to the template by DNA-boundrepressor proteins. Gro/TLE Co-repressors assemble into high order oligomericstructures [<cite idref="PUB00013903"/>] through their conserved Q domain - the Q domains are able tomediate both homo- and hetero-oligomerisation. The GP domain is able torecruit histone deacetylase to the template; this, together with otherfindings, shows that Gro/TLE proteins specifically associate with histones,and suggests that Gro/TLE Co-repressors negatively regulate transcription byinducing a silenced chromatin structure.</p> Groucho/transducin-like enhancer