Fig. 4

Depletion of PP1 complex has distinct effects S2R + cellular contractility. A-G Phase-contrast imaging of S2R + cells from the cellular contractility assay (A) in the absence of Fog or (B-G) following the perfusion of Fog. Cells were treated with (A and B) control, (C) MBS, (D) Flw, (E) MYPT-75D RNAi or double-depleted with (F) Flw and MBS, or (G) Flw and MYPT-75D RNAi. The white box in (A) denotes an uncontracted cell shown at higher magnification while the yellow box in (B) denotes a contracted cell shown at higher magnification.Yellow arrowheads indicate contracted cells, cyan arrowheads indicate rounded cells. Scale bars 10 µm. H and I Quantification of the mean (± SEM) fraction of contracted cells and fraction of rounded cells following treatment with control (yellow circles), Flw (blue circles), MBS (green circles), MYPT-75D (peach circles), Flw and MBS (magenta circles), and Flw and MYPT-75D RNAi (purple circles). The fraction of Flw depleted cells was statistically significantly lower than all other conditions, while depletion of MBS was no different than control RNAi treated samples. Depletion of MYPT-75D was also statistically significant from both control RNAi and Flw RNAi treated cells showing an intermediate phenotype. Double depletion of Flw and MBS and Flw and MYPT-75D also showed an intermediate phenotype, being statistically significantly different from control RNAi as well as single RNAi treatments of Flw, MBS, and MYPT-75D (**p-value = 0.0090,***p-value = 0.0004, ****p-value < 0.0001, one-way ANOVA with Kruskal–Wallis test, N = 3). (I) We observed a statistically significant increase in the fraction of rounded cells following Flw RNAi as compared to all other conditions. The fraction of rounded cells following MBS or MYPT-75D depletion was no different than control RNAi treated cells, while double depletion led to an intermediate cell rounding phenotype statistically significantly different from that of Flw, MBS, or MYPT-75D RNAi treated cell, as well as control cells (*p-value = 0.0417, ***p-value = 0.002, ****p-value < 0.0001, one-way ANOVA with Kruskal–Wallis test, N = 3)