Figure 8.

Summary of the study. RhoA activation induces calcium transients in all examined cell types. However, the molecular mechanisms differed among the cell types. In RPE1 and HeLa cells, the RhoA–PLCε–IP3R axis induced Ca²⁺ release from the ER (Top). Because PLCε also produces diacylglycerol (DAG), this pathway can also activate PKC signaling. In addition, extracellular calcium was required for this process. Ras did not induce calcium transients, but it may be required for PLCε recruitment to the plasma membrane. Conversely, the RhoA–ROCK–myosin II axis induced calcium transients (Bottom). Actomyosin may exert a contractile force that activates a mechanosensitive (MS) channel. Small inhibitors (U-73122, 2-APB, Y-27632, blebbistatin, and SKF96365) that blocked calcium transients are presented next to the target molecules. PM, plasma membrane.