Proteomic analyses reveal that Sky1 modulates apoptosis and mitophagy in Saccharomyces cerevisiae cells exposed to cisplatin

Abstract

Sky1 is the only member of the SR (Serine-Arginine) protein kinase family in Saccharomyces cerevisiae. When yeast cells are treated with the anti-cancer drug cisplatin, Sky1 kinase activity is necessary to produce the cytotoxic effect. In this study, proteome changes in response to this drug and/or SKY1 deletion have been evaluated in order to understand the role of Sky1 in the response of yeast cells to cisplatin. Results reveal differential expression of proteins previously related to the oxidative stress response, DNA damage, apoptosis and mitophagy. With these precedents, the role of Sky1 in apoptosis, necrosis and mitophagy has been evaluated by flow-cytometry, fluorescence microscopy, biosensors and fluorescence techniques. After cisplatin treatment, an apoptotic-like process diminishes in the Δsky1 strain in comparison to the wild-type. The treatment does not affect mitophagy in the wild-type strain, while an increase is observed in the Δsky1 strain. The increased resistance to cisplatin observed in the Δsky1 strain may be attributable to a decrease of apoptosis and an increase of mitophagy. © 2014 by the authors; licensee MDPI, Basel, Switzerland.