Serum deprivation-induced reactive oxygen species production is mediated by Romo1.
Serum deprivation-triggered increases in reactive oxygen species (ROS) are known to induce apoptotic cell death. However, the mechanism by which serum deprivation causes ROS production is not known. Since mitochondria are the main source of ROS and since mitochondrial ROS modulator 1 (Romo1) is involved in ROS production, we sought to determine if serum deprivation triggered ROS production through Romo1. To examine the relationship between Romo1 and the serum deprivation-triggered increase in ROS, we transfected Romo1 siRNA into various cell lines and looked for inhibition of mitochondrial ROS generation. Romo1 knockdown by Romo1 siRNA blocked the mitochondrial ROS production caused by serum deprivation, which originates in the mitochondrial electron transport chain. We also found that Romo1 knockdown inhibited serum deprivation-induced apoptosis. These findings suggest that Romo1-derived ROS play an important role in apoptotic cell death triggered by withdrawal of cell survival factors.
Lee
Seung Baek
SB
Laboratory of Molecular Cell Biology, Graduate School of Medicine, Korea University College of Medicine, Korea University, Seoul 136-705, Republic of Korea.
Kim
Jung Jin
JJ
Kim
Tae Woo
TW
Kim
Byung Soo
BS
Lee
Myeong-Sok
MS
Yoo
Young Do
YD
D017209:Apoptosis; D002460:Cell Line; D049109:Cell Proliferation; D016895:Culture Media, Serum-Free; D004579:Electron Transport; D055785:Gene Knockdown Techniques; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D014162:Transfection
D016895:Culture Media, Serum-Free; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D034741:RNA, Small Interfering; C513338:ROMO1 protein, human; D017382:Reactive Oxygen Species