RRC ID 70120
Author Kusama K, Suzuki Y, Kurita E, Kawarasaki T, Obara K, Okumura F, Kamura T, Nakatsukasa K.
Title Dot6/Tod6 degradation fine-tunes the repression of ribosome biogenesis under nutrient-limited conditions.
Journal iScience
Abstract Ribosome biogenesis (Ribi) is a complex and energy-consuming process, and should therefore be repressed under nutrient-limited conditions to minimize unnecessary cellular energy consumption. In yeast, the transcriptional repressors Dot6 and Tod6 are phosphorylated and inactivated by the TORC1 pathway under nutrient-rich conditions, but are activated and repress ∼200 Ribi genes under nutrient-limited conditions. However, we show that in the presence of rapamycin or under nitrogen starvation conditions, Dot6 and Tod6 were readily degraded by the proteasome in a SCFGrr1 and Tom1 ubiquitin ligase-dependent manner, respectively. Moreover, promiscuous accumulation of Dot6 and Tod6 excessively repressed Ribi gene expression as well as translation activity and caused a growth defect in the presence of rapamycin. Thus, we propose that degradation of Dot6 and Tod6 is a novel mechanism to ensure an appropriate level of Ribi gene expression and thereby fine-tune the repression of Ribi and translation activity for cell survival under nutrient-limited conditions.
Volume 25(3)
Pages 103986
Published 2022-3-18
DOI 10.1016/j.isci.2022.103986
PII S2589-0042(22)00256-5
PMID 35310337
PMC PMC8924686
IF 4.447
Resource
Yeast BYP1804, BYP1805