Persistent prion infection disturbs the function of Oct-1, resulting in the down-regulation of murine interferon regulatory factor-3

Homma, Takujiro; Ishibashi, Daisuke; Nakagaki, Takehiro; Fuse, Takayuki; Sano, Kazunori; Satoh, Katsuya; Atarashi, Ryuichiro; Nishida, Noriyuki

To confirm that Oct-1 binds to the endogenous murine IRF-3 promoter, chromatin immunoprecipitation (ChIP) assay was performed. PCR analysis revealed that the Oct-1 antibody precipitated the promoter region (nt -119 to -1) from N2a58 cells (Fig. 4a) , while the negative control (anti-rabbit IgG) did not exhibit the DNA binding activity. These data suggest that endogenous Oct-1 binds to the promoter region in vivo. Furthermore, to investigate whether the promoter activity is affected by Oct-1, pcDNA Oct-1-HA and pGL3 -119/-1 were co-transfected into N2a cells. Ectopically Oct-1 overexpression significantly increased the original promoter activities (pGL3 -119/-1 1 mock vs pGL3 -119/-1 1 pcDNA Oct-1-HA), while Oct-1 expression had no effect on the mutated promoter activities [pGL3 -119/-1 (M1) 1 mock vs pGL3 -119/-1 (M1) 1 pcDNA Oct-1-HA], indicating exogenous Oct-1 functions in the promoter region (Fig. 4b) .