Attenuated TOR signaling lengthens circadian period in <i>Arabidopsis</i>

Wang, Yan; Qin, Yumei; Li, Bin; Zhang, Yuanyuan; Wang, Lei

doi:10.1080/15592324.2019.1710935

Cited by 17 publications

(13 citation statements)

References 28 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Evidence for these more direct effects of TOR on clocks comes from studies on Drosophila ( Zheng and Sehgal, 2010 ), human cell lines ( Feeney et al, 2016 ; Walton et al, 2018 ), and both SCN and peripheral tissues of mice ( Cao, 2018 ; Lipton et al, 2017 ). In recent studies on Arabidopsis , TOR was found to be essential for glucose- and nicotinamide-mediated control of the circadian period ( Zhang et al, 2019 ), and knocking down TOR activity with inhibtors, micro-RNA or RNAi was found to lengthen the circadian period ( Wang et al, 2020 ).…”

Section: Discussionmentioning

confidence: 99%

Shared Components of the FRQ-Less Oscillator and TOR Pathway Maintain Rhythmicity in Neurospora

2021

View full text Add to dashboard Cite

Molecular models for the endogenous oscillators that drive circadian rhythms in eukaryotes center on rhythmic transcription/translation of a small number of “clock genes.” Although substantial evidence supports the concept that negative and positive transcription/translation feedback loops (TTFLs) are responsible for regulating the expression of these clock genes, certain rhythms in the filamentous fungus Neurospora crassa continue even when clock genes ( frq, wc-1, and wc-2) are not rhythmically expressed. Identification of the rhythmic processes operating outside of the TTFL has been a major unresolved area in circadian biology. Our lab previously identified a mutation ( vta) that abolishes FRQ-less rhythmicity of the conidiation rhythm and also affects rhythmicity when FRQ is functional. Further studies identified the vta gene product as a component of the TOR (Target of Rapamycin) nutrient-sensing pathway that is conserved in eukaryotes. We now report the discovery of TOR pathway components including GTR2 (homologous to the yeast protein Gtr2, and RAG C/D in mammals) as binding partners of VTA through co-immunoprecipitation (IP) and mass spectrometry analysis using a VTA-FLAG strain. Reciprocal IP with GTR2-FLAG found VTA as a binding partner. A Δ gtr2 strain was deficient in growth responses to amino acids. Free-running conidiation rhythms in a FRQ-less strain were abolished in Δ gtr2. Entrainment of a FRQ-less strain to cycles of heat pulses demonstrated that Δ gtr2 is defective in entrainment. In all of these assays, Δ gtr2 is similar to Δ vta. In addition, expression of GTR2 protein was found to be rhythmic across two circadian cycles, and functional VTA was required for GTR2 rhythmicity. FRQ protein exhibited the expected rhythm in the presence of GTR2 but the rhythmic level of FRQ dampened in the absence of GTR2. These results establish association of VTA with GTR2, and their role in maintaining functional circadian rhythms through the TOR pathway.

show abstract

Section: Discussionmentioning

confidence: 99%

Shared Components of the FRQ-Less Oscillator and TOR Pathway Maintain Rhythmicity in Neurospora

2021

View full text Add to dashboard Cite

show abstract

“…In mammals, studies have revealed that mTORC1 signaling is involving in photic entrainment of the suprachiasmatic nuclei (SCN) circadian clock, thereby linking the metabolic states to circadian clock regulation (Cao et al, 2010, 2013; Cao and Obrietan, 2010; Cao, 2018; Liu et al, 2018; Ramanathan et al, 2018). Recent studies have also shed light on the involvement of glucose–TORC1 signaling in plant circadian clock regulation (Li et al, 2019; Zhang et al, 2019; Wang et al, 2020). Vitamin B 3 (nicotinamide, NAM), a key precursor/byproduct for NAD + biosynthesis, can affect the cytosolic ATP concentration, blocking the effect of glucose–TOR energy signaling on period length adjustment, root meristem activation, and primary root growth (Zhang et al, 2019; Wang et al, 2020).…”

Section: Plant Tor Signaling: Upstream Signals and Regulatorsmentioning

confidence: 99%

“…Recent studies have also shed light on the involvement of glucose–TORC1 signaling in plant circadian clock regulation (Li et al, 2019; Zhang et al, 2019; Wang et al, 2020). Vitamin B 3 (nicotinamide, NAM), a key precursor/byproduct for NAD + biosynthesis, can affect the cytosolic ATP concentration, blocking the effect of glucose–TOR energy signaling on period length adjustment, root meristem activation, and primary root growth (Zhang et al, 2019; Wang et al, 2020). Interestingly, the circadian core oscillators, PRR5/7/9 (pseudo response regulators 5/7/9) (Harmer, 2009) also promotes TOR mRNA stability through direct inhibitions of the expression of TZF1 (tandem zinc finger 1, a processing body localized RNA‐binding protein) (Qu et al, 2014), which could directly bind to TOR mRNA and decrease its stability (Li et al, 2019).…”

Section: Plant Tor Signaling: Upstream Signals and Regulatorsmentioning

confidence: 99%

“…Interestingly, the circadian core oscillators, PRR5/7/9 (pseudo response regulators 5/7/9) (Harmer, 2009) also promotes TOR mRNA stability through direct inhibitions of the expression of TZF1 (tandem zinc finger 1, a processing body localized RNA‐binding protein) (Qu et al, 2014), which could directly bind to TOR mRNA and decrease its stability (Li et al, 2019). The discoveries of the glucose–TOR–circadian clock and PRR5/7/9–TZF1–TOR connection suggest the reciprocal regulation between the TOR signaling and circadian clock, which may serve as a conserved regulatory machinery for plant growth and adaptation (Figure 3A) (Li et al, 2019; Zhang et al, 2019; Wang et al, 2020).…”

Section: Plant Tor Signaling: Upstream Signals and Regulatorsmentioning

confidence: 99%

See 1 more Smart Citation

Plant target of rapamycin signaling network: Complexes, conservations, and specificities

Liu

Xiong

2022

JIPB

View full text Add to dashboard Cite

Target of rapamycin (TOR) is an evolutionarily conserved protein kinase that functions as a central signaling hub to integrate diverse internal and external cues to precisely orchestrate cellular and organismal physiology. During evolution, TOR both maintains the highly conserved TOR complex compositions, and cellular and molecular functions, but also evolves distinctive roles and strategies to modulate cell growth, proliferation, metabolism, survival, and stress responses in eukaryotes. Here, we review recent discoveries on the plant TOR signaling network. We present an overview of plant TOR complexes, analyze the signaling landscape of the plant TOR signaling network from the upstream signals that regulate plant TOR activation to the downstream effectors involved in various biological processes, and compare their conservation and specificities within different biological contexts. Finally, we summarize the impact of dysregulation of TOR signaling on every stage of plant growth and development, from embryogenesis and seedling growth, to flowering and senescence.

show abstract

“…Autophagy‐related genes ( ATGs ) were first discovered in yeast, and more than 40 ATGs have been characterized by different groups in the past few decades (Tsukada and Ohsumi, 1993; Masclaux‐Daubresse et al, 2017; Qi et al, 2021). TARGET OF RAPAMYCIN ( TOR ), a core metabolic regulator gene, is also a key regulator of autophagy that participates in regulation of the circadian clock (Zhang et al, 2019; Wang et al, 2020b). In plants, the TOR kinase signaling pathway regulates autophagy by phosphorylating the ATG1 and ATG13 proteins to inhibit autophagy initiation when nutrients are abundant.…”

Section: Introductionmentioning

confidence: 99%

A molecular link between autophagy and circadian rhythm in plants

Chen

et al. 2022

JIPB

View full text Add to dashboard Cite

Extremely high or low autophagy levels disrupt plant survival under nutrient starvation. Recently, autophagy has been reported to display rhythms in animals. However, the mechanism of circadian regulation of autophagy is still unclear. Here, we observed that autophagy has a robust rhythm and that various autophagy‐related genes (ATGs) are rhythmically expressed in Arabidopsis. Chromatin immunoprecipitation (ChIP) and dual‐luciferase (LUC) analyses showed that the core oscillator gene TIMING OF CAB EXPRESSION 1 (TOC1) directly binds to the promoters of ATG (ATG1a, ATG2, and ATG8d) and negatively regulates autophagy activities under nutritional stress. Furthermore, autophagy defects might affect endogenous rhythms by reducing the rhythm amplitude of TOC1 and shortening the rhythm period of CIRCADIAN CLOCK‐ASSOCIATED 1 (CCA1). Autophagy is essential for the circadian clock pattern in seedling development and plant sensitivity to nutritional deficiencies. Taken together, our studies reveal a plant strategy in which the TOC1‐ATG axis involved in autophagy‐rhythm crosstalk to fine‐tune the intensity of autophagy.

show abstract

Attenuated TOR signaling lengthens circadian period in Arabidopsis

Cited by 17 publications

References 28 publications

Shared Components of the FRQ-Less Oscillator and TOR Pathway Maintain Rhythmicity in Neurospora

Shared Components of the FRQ-Less Oscillator and TOR Pathway Maintain Rhythmicity in Neurospora

Plant target of rapamycin signaling network: Complexes, conservations, and specificities

A molecular link between autophagy and circadian rhythm in plants

Contact Info

Product

Resources

About