FIG. 2.

Scaffold and adapter molecules in MAPK pathways. MAPK scaffolds and adapters (gray shading) are thought to promote the formation of oligomeric protein complexes with components that function in a specific MAPK module. Scaffolds have been identified in S. cerevisiae (Ste5 and Pbs2) and mammals (MP1 and JIP1). MKK4 may have scaffolding properties comparable to those of PBS2.