Tim18, a Component of the Mitochondrial Translocator, Mediates Yeast Cell Death Induced by Arsenic

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Li Du, Yong Yu, Zidong Li, Jingsi Chen, Yan Liu, Yongjing Xia, and Xiangjun Liu^*

School of Medicine, Tsinghua University, Beijing, 100084, P. R. China; fax: (8610) 627-92997; E-mail: dul03@mails.tsinghua.edu.cn; frankliu@mail.tsinghua.edu.cn

^* To whom correspondence should be addressed.

Received March 15, 2007; Revision received April 20, 2007

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Evidence is presented that Tim18, a mitochondria translocase, plays a role in the previously described apoptosis induced by arsenite in Saccharomyces cerevisiae. Tim18 deletion mutant exhibited resistance to arsenite. After arsenite treatment, both the wild type and Tim18-deficient cells showed reactive oxygen species (ROS) production. Arsenite induced the higher expression of tim18 in wild type yeast cells. We found that the tim18 deletion mutant also exhibited resistance to other apoptotic stresses such as acetic acid, H₂O₂, and hyperosmotic stress. These results suggest that Tim18 is important for yeast cell death induced by arsenic, and it may act downstream of ROS production.

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KEY WORDS: Tim18, apoptosis, ROS, yeast, arsenic

DOI: 10.1134/S0006297907080056

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