Recycling of iron via autophagy is critical for the transition from glycolytic to respiratory growth

Kawamata, Tomoko; Matsunami, Miou; Ohsumi, Yoshinori

doi:10.1074/jbc.m116.762963

Cited by 27 publications

(35 citation statements)

References 43 publications

(44 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Elemental analysis by ICP-MS was performed as described in Ref. 36. Measurement of cellular glucose concentration was performed using a glucose assay kit (F-kit D-glucose, J. K. International).…”

Section: Other Proceduresmentioning

confidence: 99%

Zinc starvation induces autophagy in yeast

Kawamata

Matsunami

Sasaki

et al. 2017

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

Zinc is an essential nutrient for all forms of life. Within cells, most zinc is bound to protein. Because zinc serves as a catalytic or structural cofactor for many proteins, cells must maintain zinc homeostasis under severely zinc-deficient conditions. In yeast, the transcription factor Zap1 controls the expression of genes required for uptake and mobilization of zinc, but to date the fate of existing zinc-binding proteins under zinc starvation remains poorly understood. Autophagy is an evolutionarily conserved cellular degradation/recycling process in which cytoplasmic proteins and organelles are sequestered for degradation in the vacuole/lysosome. In this study, we investigated how autophagy functions under zinc starvation. Zinc depletion induced non-selective autophagy, which is important for zinclimited growth. Induction of autophagy by zinc starvation was not directly related to transcriptional activation of Zap1. Instead, TORC1 inactivation directed zinc starvation-induced autophagy. Abundant zinc proteins, such as Adh1, Fba1, and ribosomal protein Rpl37, were degraded in an autophagy-dependent manner. But the targets of autophagy were not restricted to zinc-binding proteins. When cellular zinc is severely depleted, this non-selective autophagy plays a role in releasing zinc from the degraded proteins and recycling zinc for other essential purposes.

show abstract

Section: Other Proceduresmentioning

confidence: 99%

Zinc starvation induces autophagy in yeast

Kawamata

Matsunami

Sasaki

et al. 2017

Journal of Biological Chemistry

Self Cite

View full text Add to dashboard Cite

show abstract

“…7C). Fet5 is a multi-copper oxidase that plays a role in iron transport [43] and recently was shown to regulate iron recycling during diauxic shift [44]. Culturing cells in media depleted of iron and copper was sufficient to increase the expression of β-gal from the CPEB translation reporter and the effect was additive to radicicol activation (Fig.…”

Section: Resultsmentioning

confidence: 99%

Transient Hsp90 suppression promotes a heritable change in protein translation

Tsvetkov

Brune

Eisen

et al. 2018

Preprint

View full text Add to dashboard Cite

The heat shock protein 90 (Hsp90) chaperone functions as a protein-folding buffer and plays a unique role promoting the evolution of new heritable traits. To investigate the role of Hsp90 in modulating protein synthesis, we screened more than 1200 proteins involved in mRNA regulation for physical interactions with Hsp90 in human cells. Among the top hits was CPEB2, which strongly binds Hsp90 via its prion domain, reminiscent of the prion-like regulation of translation of Aplysia CPEB. In a yeast model of CPEB prion-dependent translation regulation, transient inhibition of Hsp90 amplified CPEB2 prion activity and resulted in persistent translation of the CPEB reporter. Remarkably, inhibition of Hsp90 was sufficient to induce a heritable change in protein translation that persisted for 30 generations, even in the absence of exogenous CPEB. Although we identified a variety of perturbations that enhanced translation of the reporter, only Hsp90 inhibition led to persistent activation. Thus, transient loss of Hsp90 function leads to the non-genetic inheritance of a novel translational state. We propose that, in addition to sculpting the conformational landscape of the proteome, Hsp90 promotes phenotypic variation by modulating protein synthesis.

show abstract

“…Five-hundred seeds were counted and weighed after drying in a desiccator. Sample processing and metal measurements were performed as described in Horie et al (2017).…”

Section: Measurements Of Metal Contentsmentioning

confidence: 99%

Autophagy Increases Zinc Bioavailability to Avoid Light-Mediated Reactive Oxygen Species Production under Zinc Deficiency

et al. 2020

Self Cite

View full text Add to dashboard Cite

Zinc (Zn) is an essential micronutrient for plant growth. Accordingly, Zn deficiency (2Zn) in agricultural fields is a serious problem, especially in developing regions. Autophagy, a major intracellular degradation system in eukaryotes, plays important roles in nutrient recycling under nitrogen and carbon starvation. However, the relationship between autophagy and deficiencies of other essential elements remains poorly understood, especially in plants. In this study, we focused on Zn due to the property that within cells most Zn is tightly bound to proteins, which can be targets of autophagy. We found that autophagy plays a critical role during 2Zn in Arabidopsis (Arabidopsis thaliana). Autophagy-defective plants (atg mutants) failed to grow and developed accelerated chlorosis under 2Zn. As expected, 2Zn induced autophagy in wild-type plants, whereas in atg mutants, various organelle proteins accumulated to high levels. Additionally, the amount of free Zn 21 was lower in atg mutants than in control plants. Interestingly, 2Zn symptoms in atg mutants recovered under low-light, iron-limited conditions. The levels of hydroxyl radicals in chloroplasts were elevated, and the levels of superoxide were reduced in 2Zn atg mutants. These results imply that the photosynthesis-mediated Fenton-like reaction, which is responsible for the chlorotic symptom of 2Zn, is accelerated in atg mutants. Together, our data indicate that autophagic degradation plays important functions in maintaining Zn pools to increase Zn bioavailability and maintain reactive oxygen species homeostasis under 2Zn in plants.

show abstract

Recycling of iron via autophagy is critical for the transition from glycolytic to respiratory growth

Cited by 27 publications

References 43 publications

Zinc starvation induces autophagy in yeast

Zinc starvation induces autophagy in yeast

Transient Hsp90 suppression promotes a heritable change in protein translation

Autophagy Increases Zinc Bioavailability to Avoid Light-Mediated Reactive Oxygen Species Production under Zinc Deficiency

Contact Info

Product

Resources

About