HPRT1 and infection: After 6-OHDA treatment, the protein expressions of HPRT1 and DAT as well as the extent of β-catenin phosphorylation were elevated by infection of lentiviral oe-HPRT1 and DMSO treatment in N27 dopaminergic neurons, while the transduction of oe-HPRT1 and treatment with the Wnt/β-catenin inhibitor XAV-939 could reverse the promotion of HPRT1 on the extent of β-catenin phosphorylation (Figure 4A).