[Primary cilium acts as an oxygen sensor in PC12 cells].

<b>Objective:</b> To investigate the function of primary cilium as an oxygen sensor in PC12 cells. <b>Methods:</b> The PC12 cells were transfected with IFT88 siRNA. The nuclear translocation of hypoxia inducible factor-1α (HIF-1α), nuclear factor erythroid-2 related factor 2 (Nrf2), and ciliogenesis were observed by immunofluorescence staining; and the mRNA expressions of <i>HIF-1α, Nrf2</i>, vascular endothelial growth factor (<i>VEGF</i>) and superoxide dismutase (<i>SOD</i>) were detected by real-time RT-PCR. <b>Results:</b> The ciliogenesis was inhibited in PC12 cells transfected with IFT88 siRNA. In hypoxia group and scramble control group, nuclear translocations of HIF-1α and Nrf2 were observed and mRNA expressions of <i>HIF-1α, Nrf2, VEGF</i> were increased, and those of <i>SOD</i> were decreased. While in PC12 cells transfected with IFT88 siRNA, nuclear translocations of HIF-1α and Nrf2 were not observed, and mRNA expressions of <i>HIF-1α, Nrf2, VEGF</i> were inhibited, and mRNA expression of <i>SOD</i> was increased. <b>Conclusion:</b> Primary cilia may act as an oxygen sensor to transfer the information related to hypoxia and oxidative stress into cells, activating intracellular defense mechanism against the hypoxic injuries.