TY - JOUR
T1 - Tor and the Sin3-Rpd3 complex regulate expression of the mitophagy receptor protein Atg32 in yeast
AU - Aihara, Masamune
AU - Jin, Xiulian
AU - Kurihara, Yusuke
AU - Yoshida, Yutaka
AU - Matsushima, Yuichi
AU - Oku, Masahide
AU - Hirota, Yuko
AU - Saigusa, Tetsu
AU - Aoki, Yoshimasa
AU - Uchiumi, Takeshi
AU - Yamamoto, Tadashi
AU - Sakai, Yasuyoshi
AU - Kang, Dongchon
AU - Kanki, Tomotake
PY - 2014
Y1 - 2014
N2 - When mitophagy is induced in Saccharomyces cerevisiae, the mitochondrial outer membrane protein ScAtg32 interacts with the cytosolic adaptor protein ScAtg11. ScAtg11 then delivers the mitochondria to the pre-autophagosomal structure for autophagic degradation. Despite the importance of ScAtg32 for mitophagy, the expression and functional regulation of ScAtg32 are poorly understood. In this study, we identified and characterized the ScAtg32 homolog in Pichia pastoris (PpAtg32). Interestingly, we found that PpAtg32 was barely expressed before induction of mitophagy and was rapidly expressed after induction of mitophagy by starvation. Additionally, PpAtg32 was phosphorylated when mitophagy was induced. We found that PpAtg32 expression was suppressed by Tor and the downstream PpSin3-PpRpd3 complex. Inhibition of Tor by rapamycin induced PpAtg32 expression, but could neither phosphorylate PpAtg32 nor induce mitophagy. Based on these findings, we conclude that the Tor and PpSin3-PpRpd3 pathway regulates PpAtg32 expression, but not PpAtg32 phosphorylation.
AB - When mitophagy is induced in Saccharomyces cerevisiae, the mitochondrial outer membrane protein ScAtg32 interacts with the cytosolic adaptor protein ScAtg11. ScAtg11 then delivers the mitochondria to the pre-autophagosomal structure for autophagic degradation. Despite the importance of ScAtg32 for mitophagy, the expression and functional regulation of ScAtg32 are poorly understood. In this study, we identified and characterized the ScAtg32 homolog in Pichia pastoris (PpAtg32). Interestingly, we found that PpAtg32 was barely expressed before induction of mitophagy and was rapidly expressed after induction of mitophagy by starvation. Additionally, PpAtg32 was phosphorylated when mitophagy was induced. We found that PpAtg32 expression was suppressed by Tor and the downstream PpSin3-PpRpd3 complex. Inhibition of Tor by rapamycin induced PpAtg32 expression, but could neither phosphorylate PpAtg32 nor induce mitophagy. Based on these findings, we conclude that the Tor and PpSin3-PpRpd3 pathway regulates PpAtg32 expression, but not PpAtg32 phosphorylation.
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U2 - 10.1242/jcs.153254
DO - 10.1242/jcs.153254
M3 - Article
C2 - 24838945
AN - SCOPUS:84904280757
VL - 127
SP - 3184
EP - 3196
JO - The Quarterly journal of microscopical science
JF - The Quarterly journal of microscopical science
SN - 0021-9533
IS - 14
ER -