Figure 2.

A simple visual model for diversity and specificity in GPCR signaling. The cascade of events required for signal transduction via GPCRs could be considered analogous to transmission of light through a series of rotating discs with holes. Each disc represents a diverse set of factors in each family (indicated by holes on the discs) that contribute to effective signal transduction. The discs are set in motion by dynamic cellular factors (motors rotating the discs). Each set of factors could influence the dynamics of the other sets (for example, effectors depend on the subcellular location, and lipid dynamics could change trafficking). The diversity in factors depend on the size and position of the holes. Akin to light passing through the discs when a set of holes across each disc aligns, for a combination of receptor and ligand inputs, a given signaling output is generated if specific combinations of effectors at the optimal subcellular location and microenvironment ‘align’.