Upregulation of immunity-related GTPase (IRG) proteins by TNF-alpha in murine astrocytes.
We examined the effect of tumor necrosis factor-alpha (TNF-alpha) on murine primary astrocytes. Proteomic analysis demonstrated that four new spots in the TNF-alpha-treated cells relative to untreated cells. Two of them were identified as Irgb6 and Irgd, members of immunity-related GTPase (IRG) proteins which are the key mediators of interferon-gamma (IFN-gamma)-induced resistance of pathogens in numerous cells. Gene expression analysis using RT-PCR showed that TNF-alpha dose-dependently increased the expression of both proteins. Immunocytochemical analysis showed that TNF-alpha increased the abundance of both proteins. A subcellular localization study demonstrated that TNF-alpha induced the partial colocalization of both proteins with the endoplasmic reticulum (ER) and Golgi apparatus, whereas IFN-gamma did not induce the colocalization of Irgd protein with the ER and Golgi. Combined stimulation with TNF-alpha and IFN-gamma had a synergistic effect on the expression of Irgb6 and an added effect on the expression of Irgd.
Yamada
Kazutaka
K
Technological Research Laboratory, Nippon Steel Kankyo Engineering Co, Ltd, Kisarazu-shi, Chiba, Japan.
Akimoto
Hidetoshi
H
Ogawa
Yoko
Y
Kinumi
Tomoya
T
Kamagata
Yoichi
Y
Ohmiya
Yoshihiro
Y
D000818:Animals; D001253:Astrocytes / Q000187:drug effects* / Q000201:enzymology; D002478:Cells, Cultured; D019204:GTP-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D051379:Mice; D020559:Monomeric GTP-Binding Proteins / Q000096:biosynthesis* / Q000235:genetics; D040901:Proteomics; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D015854:Up-Regulation
C102949:IFI47 protein, mouse; C092499:Tgtp protein, mouse; D014409:Tumor Necrosis Factor-alpha; D019204:GTP-Binding Proteins; D020559:Monomeric GTP-Binding Proteins