Fig. 6. An action model of the mediator-related proteins in yeast and C.
elegans: the MED-6-containing mediator complex as a convergence point of
transcriptional regulation. (A) In yeast, yeast-specific mediator proteins
such as Gal11 and Hrs1 relay signals from transcription activators through the
universally conserved mediator complex that contains MED-6 to the general
transcription factors to regulate transcription. (B) In the nematode vulval
development pathway, SUR-2 is a metazoan-specific mediator-related protein
that interacts with outside signals (activated by EGF) and relays them through
the conserved mediator complex containing MED-6 to the general transcription
factors that regulate genes associated with the Ras pathway. The SynMuv
proteins including the histone deacetylase complex proteins may counteract the
mediator functions. (C) In the nematode ray developmental pathway, SOP-1 is a
mediator-related protein that represses the Wnt-mediated transcriptional
activation, which is dependent on the universally conserved mediator complex
that contains MED-6.
