p53 siRNA promotes autophagy of U2OS cells through its target gene Rap2B

The present study aims to explore the effects of p53 and its target gene Rap2B on the autophagy of U2OS cells. U2OS cells were treated with siRNA against p53, Rap2B, and PLC epsilon. Relative expressions of p53, Rap2B, and PLC epsilon were determined using quantitative polymerase chain reaction (qPCR) and Western blotting, respectively. Levels of IP3 in the cells were determined using Enzyme-linked Immunosorbent Assay (ELISA). Levels of Ca2+ were detected using Flow cytometry. Fluorescence microscopy was used to observe the autophagy of cells. Knockdown of p53 significantly decreased the expressions of Rap2B protein. Additionally, knockdown of p53 significantly decreased the mRNA levels of PLCe. The knockdown of p53, Rap2B, and PLCe significantly decreased the levels of intracellular IP3 and Ca2+ and promoted autophagy of U2OS cells. Our results demonstrated that p53-Rap2B-PLCe-IP3 signaling pathway regulated autophagy of U2OS cells.