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

In summary, our results demonstrated that Oct-1 binds to the murine IRF-3 promoter region and increases the transcription level and IRF-3 expression is reduced by prion infection. Although further investigations are required to elucidate how Oct-1 is affected in prion infection, our novel findings on the alteration of host gene expression provide new insights into the molecular biology of prions and host responses against prion infection. (a) N2a58 cell lysate was subjected to ChIP assay using anti-Oct-1 (IP: Oct-1) or normal rabbit IgG (negative control) antibodies. After the DNA was purified, the promoter region (nt -119 to -1) was amplified by PCR (see ''Materials and Methods'' in detail). (b) N2a cells were co-transfected with either pGL3 -119/-1 or pGL3 -119/-1 (M1) and either pcDNA Oct-1-HA (Oct-1) or the empty plasmid (mock). Results were normalized to the control renilla luciferase activity, and the value of (pGL3 -119/-1 1 mock) was set to 100%. Results representing the mean 6 SD, n54. P values were determined by one-way ANOVA followed by Tukey's multiple comparison (***: P , 0.001, n.s.: not significant). ScN2a58 (persistently 22L scrapie prion infected N2a58 cells) and FK-N2a58 (persistently Gerstmann-Sträussler-Scheinker syndrome-derived FK-1 prion infected N2a58 cells) cells described as previously [18] [19] [20] . All cells were cultured in a cell incubator and maintained at 5% CO 2 and 37uC.