Enhancement of oxidative stress-induced apoptosis by Hsp105alpha in mouse embryonal F9 cells.
Hsp105alpha is one of the major mammalian heat shock proteins that belongs to the HSP105/110 family, and is expressed at especially high levels in the brain as compared with other tissues in mammals. Previously, we showed that Hsp105alpha prevents stress-induced apoptosis in neuronal PC12 cells, and is a novel anti-apoptotic neuroprotective factor in the mammalian brain. On the other hand, we have also demonstrated that Hsp105alpha is expressed transiently at high levels during mouse embryogenesis and is found not only in various tissues but also in apoptotic cells. In the present study, to elucidate the role of Hsp105alpha during mouse embryogenesis, we established mouse embryonal F9 cell lines that constitutively over-express Hsp105alpha. Over-expression of Hsp105alpha enhanced hydrogen peroxide-induced apoptosis by enhancing the activation of caspase-3, poly(ADP-ribose)polymerase cleavage, cytochrome c release and activation of p38 mitogen-activated protein kinase (p38). Furthermore, oxidative stress-induced apoptosis was suppressed by SB202190, a potent inhibitor of p38, in F9 cells. These findings indicated that the activation of p38 is an essential step for apoptosis in F9 cells and that Hsp105alpha enhances activation of p38, release of cytochrome c and caspase activation. Hsp105alpha may play important roles in organogenesis, during which marked apoptosis occurs, by enhancing apoptosis during mouse embryogenesis.
Department of Biochemistry, Kyoto Pharmaceutical University, Japan.
Nobuyuki
N
Yamagishi
Youhei
Y
Saito
Keiichi
K
Ishihara
Takumi
T
Hatayama
D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D020169:Caspases / Q000378:metabolism; D003574:Cytochrome c Group / Q000378:metabolism; D053938:DNA Fragmentation; D018076:DNA, Complementary / Q000235:genetics; D005314:Embryonic and Fetal Development; D004789:Enzyme Activation; D050957:HSP110 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000502:physiology*; D007093:Imidazoles / Q000494:pharmacology; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D008928:Mitochondria / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism; D018384:Oxidative Stress; D010766:Phosphorylation; D011499:Protein Processing, Post-Translational / Q000187:drug effects; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism; D011725:Pyridines / Q000494:pharmacology; D011993:Recombinant Fusion Proteins / Q000502:physiology; D018243:Teratocarcinoma / Q000473:pathology; D014162:Transfection; D014407:Tumor Cells, Cultured; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2
D020169:Caspases; D003574:Cytochrome c Group; D018076:DNA, Complementary; D050957:HSP110 Heat-Shock Proteins; D018840:HSP70 Heat-Shock Proteins; D007093:Imidazoles; D047908:Intracellular Signaling Peptides and Proteins; D020928:Mitogen-Activated Protein Kinases; D017346:Protein Serine-Threonine Kinases; D011725:Pyridines; D011993:Recombinant Fusion Proteins; D048051:p38 Mitogen-Activated Protein Kinases; D000099190:MAP-Kinase-Activated Kinase 2; C490783:Hsp105 protein, mouse; C090942:4-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5-(4-pyridyl)imidazole