Pathways of induction of peroxiredoxin I expression in osteoblasts: roles of p38 mitogen-activated protein kinase and protein kinase C.
Peroxiredoxin I (Prx I) is an oxidative stress-inducible antioxidant protein with thioredoxin peroxidase activity. Here we report that the levels of Prx I mRNA and protein are dramatically increased in a murine osteoblast cell line, MC3T3-E1, by treatment with sodium arsenate. We further studied the signaling pathways that control the induction of Prx I expression. The treatment of osteoblasts with arsenate activated ERK1/2, JNK, and p38 MAPK. Pre-treating cells with inhibitors of p38 MAPK abolished the induction of Prx I protein but had minimal effect on the induction of Prx I mRNA, suggesting that p38 MAPK activity was required for post-transcriptional regulation. The inhibition of ERK1 and ERK2 had no effect on the induction of Prx I expression. Furthermore, rottlerin, an inhibitor of protein kinase Cdelta (PKCdelta) and calmodulin kinase III, abrogated the up-regulation at both protein and mRNA levels. Staurosporine and Go6983, inhibitors for PKC, also inhibited the induction of Prx I, suggesting that protein kinase Cdelta is required for the induction by arsenate. PKCdelta was activated by arsenate treatment by in vitro kinase assays. The inhibition of PKCdelta by rottlerin did not affect the activation of p38 MAPK by arsenate. These results suggest that there are two separate signaling pathways involved in the up-regulation of Prx I protein in response to arsenate, PKCdelta required for transcriptional activation and p38 MAPK required for post-transcriptional regulation.
Li
Baojie
B
Department of Biochemistry and Molecular Biophysics, Howard Hughes Medical Institute, Columbia University, College of Physicians and Surgeons, New York, New York 10032, USA.
Ishii
Tetsuro
T
Tan
Choon Ping
CP
Soh
Jae-Won
JW
Goff
Stephen P
SP
D016475:3T3 Cells; D000098:Acetophenones / Q000494:pharmacology; D000818:Animals; D001149:Arsenates / Q000494:pharmacology; D001578:Benzopyrans / Q000494:pharmacology; D015152:Blotting, Northern; D015153:Blotting, Western; D002460:Cell Line; D004305:Dose-Response Relationship, Drug; D004789:Enzyme Activation; D005419:Flavonoids / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D051379:Mice; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism / Q000502:physiology*; D008954:Models, Biological; D010006:Osteoblasts / Q000201:enzymology / Q000378:metabolism*; D010544:Peroxidases / Q000096:biosynthesis* / Q000737:chemistry*; D054464:Peroxiredoxins; D011485:Protein Binding; D014176:Protein Biosynthesis; D011493:Protein Kinase C / Q000378:metabolism / Q000502:physiology*; D051745:Protein Kinase C-delta; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D015398:Signal Transduction; D019311:Staurosporine / Q000494:pharmacology; D013997:Time Factors; D014158:Transcription, Genetic; D048051:p38 Mitogen-Activated Protein Kinases
D000098:Acetophenones; D001149:Arsenates; D001578:Benzopyrans; D005419:Flavonoids; D007527:Isoenzymes; D012333:RNA, Messenger; C009277:sodium arsenate; D006861:Hydrogen Peroxide; C085746:rottlerin; D010544:Peroxidases; D054464:Peroxiredoxins; C497259:Prkcd protein, mouse; D011493:Protein Kinase C; D051745:Protein Kinase C-delta; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D019311:Staurosporine; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one