Double-stranded RNA-induced interferon regulatory factor-1 gene expression in FRTL-5 rat thyroid cells.
Double-stranded RNA (dsRNA) plays a role in the regulation of cell growth and apoptosis as well as in the cellular antiviral responses. However, it remains unknown if dsRNA-activated signaling systems are functional in the thyroid. Here we report the presence of the dsRNA-dependent protein kinase (PKR) in FRTL-5 rat thyroid cells. In poly(I)-poly(C) (pIC)-stimulated cells, activation of nuclear factor-kappa B (NF kappa B) binding was clearly induced. Incubation of FRTL-5 cells with pIC resulted in a marked increase in interferon regulatory factor-1 (IRF-1) mRNA and phosphorylated signal transducer and activator of transcription-1 (STAT1) levels. Addition of pIC to cells led to type I interferon (IFN) gene expression, especially IFN beta, which can induce STAT1 phosphorylation, suggesting that dsRNA indirectly induced STAT1 phosphorylation through expression of type I IFN. Thus, our results suggest that the dsRNA-activated signaling pathway may be involved in the regulation of IFN-inducible genes in the thyroid.
Mori
K
K
Department of Medicine, Division of Nephrology, Endocrinology and Vascular Medicine, Tohoku University Graduate School of Medicine, 1-1, Seiryo-machi, Aoba-ku, Sendai 980-8574, Japan. kokimori@mail.cc.tohoku.ac.jp
Yoshida
K
K
Tani
J
J
Nakagawa
Y
Y
Hoshikawa
S
S
Ito
S
S
D000818:Animals; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects*; D050856:Interferon Regulatory Factor-1; D007370:Interferon Type I / Q000187:drug effects / Q000235:genetics; D016328:NF-kappa B / Q000378:metabolism; D010750:Phosphoproteins / Q000187:drug effects / Q000235:genetics*; D011070:Poly I-C / Q000494:pharmacology; D011485:Protein Binding / Q000187:drug effects; D012330:RNA, Double-Stranded / Q000494:pharmacology*; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D050794:STAT1 Transcription Factor; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013961:Thyroid Gland / Q000166:cytology* / Q000378:metabolism; D015534:Trans-Activators / Q000187:drug effects / Q000378:metabolism; D019892:eIF-2 Kinase / Q000032:analysis / Q000502:physiology
D004268:DNA-Binding Proteins; D050856:Interferon Regulatory Factor-1; D007370:Interferon Type I; C494259:Irf1 protein, rat; D016328:NF-kappa B; D010750:Phosphoproteins; D012330:RNA, Double-Stranded; D012333:RNA, Messenger; D050794:STAT1 Transcription Factor; C494081:Stat1 protein, rat; D015534:Trans-Activators; D019892:eIF-2 Kinase; D011070:Poly I-C