Fig. S7.

Model of Gip1-dependent trimeric G-protein shuttling. (A) Gip1 regulates G-protein shuttling by binding to its C terminus in the cytosol. Receptor stimulation causes the dissociation of G protein from Gip1, leading to G-protein translocation to the plasma membrane. (B) Gip1-mediated translocation of G proteins leads to redistribution along the chemical gradient in WT but not in gip1Δ cells. This reaction may be critical for the transduction of gradient information, especially at high chemical concentrations, to expand the range of sensitivity.