Scatterplot of the mean SA-647 versus mean GFP fluorescence calculated for every GFP + cell detected across 11 FOVs treated with either biotin + Ca 2+ ( n = 451 cells; two-tailed Pearson’s R = 0.50, P = 6.2 10 -30 ) or biotin - Ca 2+ ( n = 473 cells; two-tailed Pearson’s R = 0.69, P = 2.6 10 -67 ).