A- Co-immunofluorescence studies showing the colocalization of PLCβ2 (green,) and Gαq (red) in MDA MB 231 cells treated with control (n=50) or γ-synuclein (n=30) siRNA where the compiled colocalization values are shown in the box plot. Pearson’s coefficient between the two groups is statistically significant (p<0.001, Student’s t-test. Positive control= 0.65 +/− 0.12, negative control= 0.03 +/− 0.08). B- Sample raw FRET image of a MDA MB 231cell expressing eCFP- Gαq and eYFP- PLCβ2 with corresponding images at CFP and YFP wavelengths where the normalized FRET efficiencies for cells treated with γ-synuclein (n=30) and control (n=50) are given in the box plot were the values are found to be significantly different (p<0.001, Rank Sum Test. (Positive control = 0.44+/− 0.06, Negative control = 0.03 +/− 0.02). C- Functional results showing that reduction of γ-synuclein causes a more robust Ca2+ response. Ca2+ release was measured in MDA MB 231 cell suspensions upon the addition of 100 μM carbachol using Fura-2, where cells were treated with control or γ-synuclein siRNA, n = 6. The mean ± SEM is shown.