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Low temperature (LT) is an important environmental factor affecting the growth and yield of plants. Melatonin (MT) can effectively enhance the LT tolerance of cucumber. This study found that LT stress induced the expression of Comt1 (caffeic acid O-methyltransferase 1), with the highest expression being about 2-times that of the control. Meanwhile, the content of MT was found to be roughly 63.16% of that in the control samples. Compared with LT treatment alone, exogenous MT pretreatment upregulated the expression levels of TOR (Target of rapamycin), PIN1 (Pin-formed 1), and YUC4 (YUCCA 4) , with maximum upregulations reaching approximately 66.67%, 79.32%, and 42.86%, respectively. These results suggest that MT may modulate the tolerance of cucumber seedlings to LT stress by regulating the expression of TOR , PIN1 , and YUC4. In addition, co-treatment with AZD-8055 (a TOR inhibitor) or NPA (N-1-naphthylphthalamic acid, an auxin polar transport inhibitor) and MT attenuated MT-induced resistance to LT stress, leading to higher levels of reactive oxygen species (ROS), reduced antioxidant defense capacity, and increased damage to the membrane system in cucumber seedlings. Concurrently, the content of osmoregulatory substances and the photosynthesis decreased. These results demonstrate that both TOR and auxin were required for MT to alleviate LT-induced damage in cucumber. In summary, the present study demonstrates that TOR and auxin signaling synergistically contribute to alleviating LT damage in cucumber seedlings by exogenous MT. These findings help us understand the function of MT and provide insights into the regulatory network of MT that regulates the LT tolerance of plants. • Melatonin (MT) responds positively to low temperature (LT) stress and enhances LT tolerance in cucumber seedlings. • Under LT stress, MT induces the expression of target of rapamycin (TOR) and auxin signaling related genes. • MT pretreatment enhances LT stress tolerance through interaction with TOR and auxin signaling. [ABSTRACT FROM AUTHOR]

[Display omitted] • Isolating and sequencing the genome of F. oxysporum from potato tubers with dry rot symptoms. • SA efficiently arrests hyphal growth, sporular production and pathogenicity of F. oxysporum. • SA inhibits the activity of FoTORC1 via activating FoSNF1 in F. oxysporum. • Transgenic potato plants with interference of FoTOR1 and FoSAH1 genes prevent the occurrence of Fusarium wilt. • Providing insights SA into controlling various fungal diseases by targeting the SNF1-TORC1 pathway of pathogens. Biofungicides with low toxicity and high efficiency are a global priority for sustainable agricultural development. Phytohormone salicylic acid (SA) is an ancient medicine against various diseases in humans and activates the immune system in plants, but little is known of its function as a biofungicide. Here, Fusarium oxysporum , the causal agent of devastating Fusarium wilt and immunodepressed patients, was used as a model system to explore whether SA can enter the pathogen cells and suppress key targets of the pathogen. Oxford Nanopore MinION sequencing and high-throughput chromosome conformation capture (Hi-C) sequencing were used to analyzed the genome of F. oxysporum. In addition, RNA-seq, qRT-PCR, and western blotting were conducted to detect gene and protein expression levels. We isolated and sequenced the genome of F. oxysporum from potato dry rot, and the F. oxysporum included 12 chromosomes and 52.3 Mb genomic length. Pharmacological assays showed that exogenous application of SA can efficiently arrest hyphal growth, spore production, and pathogenicity of F. oxysporum , whereas endogenous salicylate hydroxylases significantly detoxify SA. The synergistic growth inhibition of F. oxysporum was observed when SA was combined with rapamycin. Kinase assays showed that SA inhibits FoTOR complex 1 (FoTORC1) by activating FoSNF1 in vivo. Transgenic potato plants with the interference of FoTOR1 and FoSAH1 genes inhibited the invasive growth of hyphae and significantly prevented the occurrence of Fusarium wilt. This study revealed the underlying mechanisms of SA against F. oxysporum and provided insights into SA in controlling various fungal diseases by targeting the SNF1-TORC1 pathway of pathogens. [ABSTRACT FROM AUTHOR]

Plant growth is intimately linked to the availability of carbon and energy status. The Target of rapamycin (TOR) pathway is a highly relevant metabolic sensor and integrator of plant-assimilated C into development and growth. The cell wall accounts for around a third of the cell biomass, and the investment of C into this structure should be finely tuned for optimal growth. The plant C status plays a significant role in controlling the rate of cell wall synthesis. TOR signaling regulates cell growth and expansion, which are fundamental processes for plant development. The availability of nutrients and energy, sensed and integrated by TOR, influences cell division and elongation, ultimately impacting the synthesis and deposition of cell wall components. The plant cell wall is crucial in environmental adaptation and stress responses. TOR senses and internalizes various environmental cues, such as nutrient availability and stresses. These environmental factors influence TOR activity, which modulates cell wall remodeling to cope with changing conditions. Plant hormones, including auxins, gibberellins, and brassinosteroids, also regulate TOR signaling and cell wall-related processes. The connection between nutrients and cell wall pathways modulated by TOR are discussed. [ABSTRACT FROM AUTHOR]

Target Of Rapamycin (TOR) represents a ubiquitous kinase complex that has emerged as a central regulator of cell growth and metabolism in nearly all eukaryotic organisms. TOR is an evolutionarily conserved protein kinase, functioning as a central signaling hub that integrates diverse internal and external cues to regulate a multitude of biological processes. These processes collectively exert significant influence on plant growth, development, nutrient assimilation, photosynthesis, fruit ripening, and interactions with microorganisms. Within the plant domain, the TOR complex comprises three integral components: TOR, RAPTOR, and LST8. This comprehensive review provides insights into various facets of the TOR protein, encompassing its origin, structure, function, and the regulatory and signaling pathways operative in photosynthetic organisms. Additionally, we explore future perspectives related to this pivotal protein kinase. [ABSTRACT FROM AUTHOR]

The aim of this study was to contribute to the understanding of auxin signaling and response in the model alga Chlamydomonas reinhardtii. We show that high concentrations of indole-3-acetic acid (IAA) arrested cell division and promoted cell enlargement, which allowed maintenance of biomass production. Besides, high IAA induced carbon reserve accumulation. No synergistic or additive effect was observed after the combined supplementation of IAA and rapamycin, suggesting IAA and TOR (Target of Rapamycin) might share the same signaling pathway for the control of cell cycle. High levels of IAA strongly up-regulated the expression of the cell-cycle genes CDKB1 and CYCA1, and also transiently increased the levels of TOR transcripts. Cells previously incubated with IAA performed better under oxidative stress conditions, but not under saline stress, suggesting specificity of this response. The plant YUCCA inhibitor Bbo produced a dose-dependent inhibition of growth and chlorophyll accumulation, suggesting YUC-like genes implication in IAA biosynthesis in the alga, and that they might be essential for Chlamydomonas growth. Co-culture of Chlamydomonas and Arabidopsis thaliana indicated that the microalga synthesized and released biologically active form(s) of auxin. This study contributes to extending the current knowledge of IAA biosynthesis and response in algae, and its physiological, phylogenetic/evolutionary and biotechnological implications. [Display omitted] • High IAA arrests cell division and increases cell size, sustaining biomass production. • High IAA induces carbon reserves accumulation. • IAA may be essential to the proper progress of the cell cycle. • IAA pretreatment protects cells against oxidative stress conditions. • Evidence is provided that Chlamydomonas synthesizes and releases active auxin. [ABSTRACT FROM AUTHOR]

Potassium (K) is an essential inorganic nutrient needed by plants for their growth and development. The conserved target of rapamycin (TOR) kinase, a well-known nutrition signaling integrator, has crucial roles in regulating growth and development in all eukaryotes. Emerging evidence suggests that TOR is a core regulator of nutrient absorption and utilization in plants. However, it is still unclear whether there is a causative link between the TOR pathway and potassium absorption. Here, we show that the expression of some potassium transporters and channels was regulated by TOR, and the suppression of TOR activity significantly affected potassium uptake in Arabidopsis and potato. Furthermore, we discovered that a Type 2A phosphatase-associated protein of 46 kDa (TAP46), a direct TOR downstream effector, could interact with CBL-interacting protein kinase 23 (CIPK23) in Arabidopsis and potato. In Arabidopsis , the K+ channel AKT1 conducting K+ uptake was significantly regulated by Calcineurin B-like Calcium Sensor Protein 1/9 (CBL1/9)-CIPK23 modules. We found that the cbl1cbl9 , cipk23 (lks1-2 and lks1-3), and akt1 mutants were more hyposensitive to the TOR inhibitor than the wild-type, and the TOR inhibitor induced the downregulation of K+ uptake rate in the wild-type more than in these mutants. In addition, the overexpression of CIPK23 could effectively restore the defects in growth and potassium uptake induced by the TOR inhibitors. Thus, our work reveals a link between TOR signaling and CIPK23 and provides new insight into the regulation of potassium uptake in plants. • TOR plays a vital role in regulating K+ uptake in plants. • TAP46/PP2A physically interacts with CIPK23, a well identified regulator of K+ uptake, in Arabidopsis and potato. • Overexpression of CIPK23 can promote plant growth and K+ uptake under conditions of TOR inhibition. [ABSTRACT FROM AUTHOR]

Target of rapamycin (TOR) is a protein kinase that coordinates metabolism with nutrient and energy availability in eukaryotes. TOR and its primary interactors, RAPTOR and LST8, have been remarkably evolutionarily static since they arose in the unicellular last common ancestor of plants, fungi, and animals, but the upstream regulatory mechanisms and downstream effectors of TOR signaling have evolved considerable diversity in these separate lineages. Here, I focus on the roles of exaptation and adaptation in the evolution of novel signaling axes in the TOR network in multicellular eukaryotes, concentrating especially on amino acid sensing, cell-cell signaling, and cell differentiation. The protein kinase TOR is an evolutionary "TORtoise" that has not significantly evolved since the last eukaryotic common ancestor. Here, I discuss recent studies illuminating how signaling networks upstream and downstream of TOR have evolved through exaptation and adaptation to coordinate metabolism in diverse eukaryotic lineages. [ABSTRACT FROM AUTHOR]

Microalgae can produce large quantities of triacylglycerols (TAGs) and other neutral lipids that are suitable for making biofuels and as feedstocks for green chemistry. However, TAGs accumulate under stress conditions that also stop growth, leading to a trade-off between biomass production and TAG yield. Recently, in the model marine diatom Phaeodactylum tricornutum it was shown that inhibition of the target of rapamycin (TOR) kinase boosts lipid productivity by promoting TAG production without stopping growth. We believe that basic knowledge in this emerging field is required to develop innovative strategies to improve neutral lipid accumulation in oleaginous microalgae. In this minireview, we discuss current research on the TOR signaling pathway with a focus on its control on lipid homeostasis. We first provide an overview of the well characterized roles of TOR in mammalian lipogenesis, adipogenesis and lipolysis. We then present evidence of a role for TOR in controlling TAG accumulation in microalgae, and draw parallels between the situation in animals, plants and microalgae to propose a model of TOR signaling for TAG accumulation in microalgae. [ABSTRACT FROM AUTHOR]

This study was conducted to explore the regulatory role of the target of rapamycin complex 1 (TORC1) signaling pathway in crop milk synthesis in breeding pigeons (Columba livia). Three groups of breeding pigeons in the lactation period (n = 30 pairs/group) were respectively injected with rapamycin (RAPA, a specific inhibitor of the target of rapamycin complex) at doses of 0 (vehicle, control), 0.6, or 1.2 mg/kg body weight (BW)/day via the wing vein for 7 days. The average daily feed intake (ADFI) and BW of the breeding pigeons and the BW of young squabs were respectively recorded throughout the experimental period. The breeding pigeons were sacrificed to collect their crop tissues, crop milk, and serum on the eighth day of the experiment. The results showed that neither 0.6 nor 1.2 mg/kg BW RAPA injection affected BW loss or ADFI in breeding pigeons (P > 0.05), while crop thickness and crop relative weight were significantly decreased (P < 0.05) in the 1.2 mg/kg BW rapamycin-injected group. Simultaneously, RAPA (especially at 1.2 mg/kg BW) decreased the crude protein, αs1-casein, αs2-casein, β-casein, and amino acid contents (Asp, Thr, Ser, Glu, Gly, Ala, Cys, Val, Met, Ile, Leu, Tyr, Lys, His, Arg, and Pro) of crop milk (P < 0.05) and the concentrations of albumin, total protein, and uric acid in the serum of breeding pigeons (P < 0.05). Additionally, the expression of TORC1 pathway-related proteins (TORC1, S6K1, S6, 4EBP1, and eIF4E) was downregulated in the crop tissues of breeding pigeons by 0.6 or 1.2 mg/kg BW/day RAPA injection (P < 0.05). Accordingly, the average daily gain (ADG) of young squabs declined, and the mortality rate increased significantly (P < 0.05). Together, the results showed that RAPA reduced protein and amino acid levels in the crop milk of breeding pigeons and retarded young squab growth, suggesting a crucial role of TORC1 in crop milk synthesis in breeding pigeons. [ABSTRACT FROM AUTHOR]

Abstract A 6-week growth trial was conducted to study the effects of dietary protein levels on growth, feed utilization, ammonia excretion and expression of growth related genes of juvenile giant grouper (Epinephelus lanceolatus). Seven experimental diets were formulated to contain 38% (P38), 42% (P42), 46% (P46), 50% (P50), 54% (P54), 58% (P58) or 62% (P62) dietary crude protein (CP) (dry-matter basis). Experimental fish (average initial body weight: 5.39 ± 0.05 g) were randomly distributed into 21 glass tanks (length 60 cm × width 45 cm × height 50 cm) at a density of 15 fish / tank and fed their prescribed diets to apparent satiation twice daily (08: 00 and 16:30) by hand. All tanks were connected to the mechanical and biological water filters as a recycling system, and each experimental treatment had three replicates. At the end of the trial, two fish per tank were collected for whole-body composition analysis, and other three fish per tank were individually weighed and dissected to obtain liver and intraperitoneal fat (IPF) weights. Total RNA was extracted from grouper liver and pituitary using Trizol Reagent. Results showed that weight gain% (WG%) of fish was remarkably increased as dietary CP levels increased from 38% to 54%, and when it continued to rise from 54% to 62%, there only had a slight increment in values of this parameter. Analysis of a nonlinear exponential model indicated that the optimal dietary protein requirement for maximum growth of giant grouper was estimated to be 56% of dry matter. Daily feed intake (DFI) and feed conversation ratio (FCR) were decreased with the increasing of dietary CP levels. Fish fed P38 and P42 showed lower lipid retention efficiency (LRE) and lower contents of liver lipid, whole-body protein as well as muscle protein than fish fed other dietary CP levels. The water ammonia production was linearly related to dietary CP levels. Expression of pituitary growth hormone (GH) and hepatic target of rapamycin (TOR), S6 kinase 1 (S6K1) as well as insulin growth factor I (IGF I) were lower in fish fed P38, P42 and P46 than those in fish fed P50, P54, P58 and P62. Generally, the optimal dietary crude protein requirement for maximum growth of giant grouper was estimated to be 56% of dry matter. Highlights • Optimal dietary protein requirement for maximum WG% of giant grouper was estimated to be 56% of dry matter. • Expression of growth hormone, insulin growth factor I in pituitary was affected by dietary CP levels. • Expression of target of rapamycin, S6 kinase 1 in liver was affected by dietary CP levels. [ABSTRACT FROM AUTHOR]

In this study, the mechanism that lithium (Li) promotes the production of reactive oxygen species (ROS) via the glycogen synthase kinase-3β (GSK-3β)/tuberous sclerosis complex 2 (TSC2)/target of rapamycin (TOR) signaling was investigated in the gill of zebrafish ( Danio rerio ). After the zebrafish were treated by 25 and 50 mg/L Li + , the mRNA expression of GSK-3β and TSC2 was inhibited, but the expression of TOR was induced in the gill of zebrafish. The levels of hydrogen peroxide (H 2 O 2 ), superoxide anion (O 2 ·- ), and hydroxy radical (·OH) as well as the activity of superoxide dismutase (SOD) were increased, while the activities of catalase (CAT), glutathione peroxidase (GSH-PX), and peroxidase (POD) were decreased by 25 and 50 mg/L Li + treatments. In the ZF4 cells, the mRNA expression of GSK-3β and TSC2 was inhibited, but TOR expression was induced by 1, 5, and 10 mmol/L Li + treatments. To further confirm that lithium promoted ROS production via GSK-3β inhibition, GSK-3β RNA was interfered. It was found that the interference of GSK-3β RNA induced the TSC2/TOR signaling. The levels of H 2 O 2 , O 2 ·- , and ·OH were increased, but the activities of CAT, GSH-PX, and POD were decreased by GSK-3β RNA interference. In addition, lithium decreased the mitochondrial membrane potential (MMP) with Rhodamine-123 assay, but increased the levels of ROS by 2′,7′-dichlorofluorescein diacetate (DCFH-DA) assay. The present results indicated that lithium promoted the ROS production through the GSK-3β/TSC2/TOR signaling in the gill of zebrafish. [ABSTRACT FROM AUTHOR]

The quality of Beauveria bassiana conidia directly affects the virulence against insects. In this study, continuous subculturing of B. bassiana on both rice grains and potato dextrose agar (PDA) resulted in 55 and 49 % conidial yield reduction after 12 passages and 68 and 60 % virulence reduction after 20 and 12 passages at four d post-inoculation, respectively. The passage through Tenebrio molitor and Spodoptera exigua restored the virulence of rice and PDA subcultures, respectively. To explore the molecular mechanisms underlying the conidial quality and the decline of virulence after multiple subculturing, we investigated the conidial proteomic changes. Successive subculturing markedly increased the protein levels in oxidative stress response, autophagy, amino acid homeostasis, and apoptosis, but decreased the protein levels in DNA repair, ribosome biogenesis, energy metabolism, and virulence. The nitro blue tetrazolium assay verified that the late subculture's colony and conidia had a higher oxidative stress level than the early subculture. A 2A-type protein phosphatase and a Pleckstrin homology domain protein Slm1, effector proteins of the target of rapamycin (TOR) complex 1 and 2, respectively, were dramatically increased in the late subculture. These results suggest that TOR signalling might be associated with ageing in B. bassiana late subculture, in turn affecting its physiological characteristics and virulence. [ABSTRACT FROM AUTHOR]

The nature of consciousness has been debated for centuries. It can be understood as part and parcel of the natural progression of life from unicellular to multicellular, calcium fluxes mediating communication within and between cells. Consciousness is the vertical integration of calcium fluxes, mediated by the Target of Rapamycin gene integrated with the cytoskeleton. The premise of this paper is that there is a fundamental physiologic integration of the organism with the environment that constitutes consciousness. [ABSTRACT FROM AUTHOR]

Reduced reproduction and dietary restriction each extend lifespan in many animal models, but possible contributions of nutrient oxidation and allocation are largely unknown. Ovariectomy and eating 70% of ad libitum-feeding each extend lifespan in lubber grasshoppers. When feeding levels between the two groups are matched, ovariectomy increases fat and protein storage while dietary restriction reduces fat storage. Because of these disparities in nutrient investment, metabolism may differ between these two life-extending treatments. Therefore, we examined the allocation and organismal oxidation of one representative of each macronutrient class: leucine, oleic acid, and glucose. Ovariectomy and dietary restriction each increased oxidation of dietary leucine. Dietary leucine may play a special role in aging because amino acids stimulate cellular growth. Speeding oxidation of leucine may attenuate cellular growth. Allocation of leucine to muscle was the clearest difference between ovariectomy and dietary restriction in this study. Ovariectomy reduced allocation of leucine to femur muscle, whereas dietary restriction increased allocation of leucine to femur muscle. This allocation likely corresponds to muscle maintenance for locomotion, suggesting dietary restriction increases support for locomotion, perhaps to search for food. Last, ovariectomy decreased oxidation of dietary oleic acid and glucose, perhaps to save them for storage, but the site of storage is unclear. This study suggests that the oxidation of branched-chain amino acids may be an underappreciated mechanism underlying lifespan extension. [ABSTRACT FROM AUTHOR]

The target of rapamycin (TOR) signaling pathway regulates fundamental intracellular functions critical for cell viability and proliferation. Manipulation of TOR in high lipid-producing microalgae may help overcome the trade-off between biomass production and lipid yield that still impairs the viable production of biofuel from microalgae. In this study, we inhibited the TOR kinase in the model diatom Phaeodactylum tricornutum using the selective TOR inhibitor AZD-8055, and analyzed cell proliferation, chlorophyll content, lipid synthesis and carbon metabolism. AZD-8055 inhibits cell proliferation in a dose-dependent manner compared to N deprivation which stops growth. Microscopy, flow cytometry, and quantitative analyses of lipids also demonstrated that AZD-8055 treatment strongly promotes triacylglycerol (TAG) accumulation while decreasing the quantity of sterols. The TAG productivity of AZD-8055 treated cultures was significantly higher than for N deprived cultures. Measurement of the activities of the key metabolic enzymes glyceraldehyde phosphate dehydrogenase (GAPDH), glucose-6-phosphate dehydrogenase (G6PDH) and malate dehydrogenase (MDH) revealed opposite effects for AZD-8055 treatment and N-starvation on the activity of the glycolytic enzyme GAPDH. This suggests that TOR inhibition and N starvation may have distinct impacts on general metabolism and lipid accumulation. Our main finding is that treating cultures with AZD-8055 results in higher TAG productivity than N starvation in P. tricornutum . The chemical or genetic manipulation of the TOR signaling pathway in P. tricornutum and other diatoms may lead to the development of strains or approaches suitable for the enhanced production of TAGs for biofuel. [ABSTRACT FROM AUTHOR]

Summary Dietary restriction promotes health and longevity across taxa through mechanisms that are largely unknown. Here, we show that acute yeast restriction significantly improves the ability of adult female Drosophila melanogaster to resist pathogenic bacterial infections through an immune pathway involving downregulation of target of rapamycin (TOR) signaling, which stabilizes the transcription factor Myc by increasing the steady-state level of its phosphorylated forms through decreased activity of protein phosphatase 2A. Upregulation of Myc through genetic and pharmacological means mimicked the effects of yeast restriction in fully fed flies, identifying Myc as a pro-immune molecule. Short-term dietary or pharmacological interventions that modulate TOR-PP2A-Myc signaling may provide an effective method to enhance immunity in vulnerable human populations. [ABSTRACT FROM AUTHOR]

The target gene of rapamycin ( TOR ) is conserved from invertebrates to vertebrates, and plays critical roles in cell growth, nutrient sensing, lifespan and reproduction. In this paper, we employed RNA interference (RNAi) to study the function of TOR in male brown planthoppers (BPH), Nilaparvata lugens . Here we discovered that no offspring was produced when wildtype females BPH mated with NlTOR RNAi males. To understand the influence of NlTOR on male BPH infertility, we dissected the reproductive system of a NlTOR RNAi male, and found that the testes were normal and the seminal vesicles were full of sperm, while the accessory gland was poorly developed after knocking down NlTOR expression. Furthermore, transmission electron microscopy data showed defective structure of epithelial cells of the accessory gland, and the deferent duct was collapsed. Also, behavioral data revealed that wildtype virgin females refused to mate with NlTOR RNAi males, and the acoustic signals of ds NlTOR males differed from controls. Our results indicate that NlTOR plays an essential role in the development of the male BPH reproductive system and regulates mating behavior. [ABSTRACT FROM AUTHOR]

Molting in decapod crustaceans is controlled by molt-inhibiting hormone (MIH), an eyestalk neuropeptide that suppresses production of ecdysteroids by a pair of molting glands (Y-organs or YOs). Eyestalk ablation (ESA) activates the YOs, which hypertrophy and increase ecdysteroid secretion. At mid premolt, which occurs 7–14 days post-ESA, the YO transitions to the committed state; hemolymph ecdysteroid titers increase further and the animal reaches ecdysis ~ 3 weeks post-ESA. Two conserved signaling pathways, mechanistic target of rapamycin (mTOR) and transforming growth factor-β (TGF-β), are expressed in the Gecarcinus lateralis YO. Rapamycin, an mTOR antagonist, inhibits YO ecdysteroidogenesis in vitro . In this study, rapamycin lowered hemolymph ecdysteroid titer in ESA G. lateralis in vivo ; levels were significantly lower than in control animals at all intervals (1–14 days post-ESA). Injection of SB431542, an activin TGF-β receptor antagonist, lowered hemolymph ecdysteroid titers 7 and 14 days post-ESA, but had no effect on ecdysteroid titers at 1 and 3 days post-ESA. mRNA levels of mTOR signaling genes Gl-mTOR , Gl-Akt , and Gl-S6k were increased by 3 days post-ESA; the increases in Gl-mTOR and Gl-Akt mRNA levels were blocked by SB431542. Gl-elongation factor 2 and Gl-Rheb mRNA levels were not affected by ESA, but SB431542 lowered mRNA levels at Days 3 and 7 post-ESA. The mRNA level of an activin TGF-β peptide, Gl-myostatin-like factor ( Mstn ), increased 5.5-fold from 0 to 3 days post-ESA, followed by a 50-fold decrease from 3 to 7 days post-ESA. These data suggest that (1) YO activation involves an up regulation of the mTOR signaling pathway; (2) mTOR is required for YO commitment; and (3) a Mstn-like factor mediates the transition of the YO from the activated to the committed state. [ABSTRACT FROM AUTHOR]

Aging is the strongest known risk factor for Alzheimer's disease (AD). With the discovery of the mechanistic target of rapamycin (mTOR) as a critical pathway controlling the rate of aging in mice, molecules at the interface between the regulation of aging and the mechanisms of specific age-associated diseases can be identified. We will review emerging evidence that mTOR-dependent brain vascular dysfunction, a universal feature of aging, may be one of the mechanisms linking the regulation of the rate of aging to the pathogenesis of Alzheimer's disease. This article is part of a Special Issue entitled: Vascular Contributions to Cognitive Impairment and Dementia edited by M. Paul Murphy, Roderick A. Corriveau and Donna M. Wilcock. [ABSTRACT FROM AUTHOR]

Cranberry is an excellent source of dietary antioxidants. The present study investigated the effect of cranberry anthocyanin (CrA) extract on the lifespan of fruit flies with focus on its interaction with aging-related genes including superoxide dismutase (SOD), catalase (CAT), methuselah (MTH), insulin receptor (InR), target of rapamycin (TOR), hemipterus (Hep), and phosphoenolpyruvate carboxykinase (PEPCK). Results showed that diet containing 20 mg/mL CrA could significantly prolong the mean lifespan of fruit flies by 10% compared with the control diet. This was accompanied by up-regulation of SOD1 and down-regulation of MTH, InR, TOR and PEPCK. The stress resistance test demonstrated that CrA could reduce the mortality rate induced by H2O2 but not by paraquat. It was therefore concluded that the lifespan-prolonging activity of CrA was most likely mediated by modulating the genes of SOD1, MTH, InR, TOR and PEPCK. [ABSTRACT FROM AUTHOR]

The role of leucine (Leu) in the regulation of the intestinal immune status, immune-related signalling molecules and tight junction (TJ) protein transcript abundance in the intestine of grass carp ( Ctenopharyngodon idella ) was investigated. Six iso-nitrogenous diets that contained graded levels of Leu (7.1–17.1 g Leu kg − 1 diets) were fed to the fish for 8 weeks. Compared with the control group, appropriate Leu supplementation increased ( P < 0.05) the following: (1) the lysozyme activity, acid phosphatase activity and complement component 3 (C3) content in all intestinal segments; (2) the mRNA levels of interleukin 10, inhibitor factor κBα (IκBα) and target of rapamycin (TOR) in the mid and distal intestine as well as transforming growth factor β1 in all intestinal segments; and (3) the transcript levels for claudin b, claudin 3, claudin 15, occludin and zonula occludens-1 (ZO-1) in the intestine of young grass carp. At the same time, appropriate Leu supplementation down-regulated the mRNA levels of tumour necrosis factor α, interleukin 8 and nuclear factor κB p65 (NF-κB p65) in the mid and distal intestine of young grass carp ( P < 0.05). Interestingly, the transcript levels for claudin c and claudin 12 showed no significant differences among the groups in the intestine of young grass carp. In conclusion, the positive effect of Leu on intestinal health is associated with the improvement of the intestinal immune status and the regulation of immune-related signalling molecules and tight junction transcripts of fish. [ABSTRACT FROM AUTHOR]

L-arginine (Arg) is an indispensable amino acid in avians and is required for growth. The aim of this study was to investigate the effects of L-Arg on protein synthesis and genes expreµion involved in target of rapamycin (TOR) signaling pathway in chicken enterocytes. Cells were cultured for 4 days in L-Arg-free Dulbecco's modified Eagle's medium containing 10, 100, 200, 400, or 600 µM L-Arg. Cell growth, cell cycle, protein synthesis, and protein degradation as well as mRNA expreµion levels of TOR, ribosomal protein S6 kinase 1 (S6K1), and eukaryotic initiation factor 4E-binding protein 1 (4E-BP1) were determined. The results showed that cell viability was enhanced by L-Arg with a maximal response at 10 to 400 µM. Increasing extracellular concentrations of L-Arg from 10 to 400 µM increased the cells in S and G2/M phase to a significant extent and decreased cell numbers in G0/G1 phase. Further more, addition of 100, 200, or 400 µM L-Arg to culture medium increased protein synthesis and reduced protein degradation in chicken intestinal epithelial cells. Consistent with the data on cell growth and protein turnover, supplementation of 100, 200, or 400 µM L-Arg increased the mRNA abundances of TOR, 4E-BP1, and S6K1. It was concluded the action of L-Arg involves in upregulating the genes expreµion of TOR cell signaling pathway which increases protein synthesis and reduces protein degradation. [ABSTRACT FROM AUTHOR]

Highlights: [•] There is an extensive PIK polymorphism at genomic localization level in T. cruzi. [•] FYVE-PIK is a trypanosomatid PIK gene that might be acquired by horizontal transfer. [•] The localization of TOR proteins within Trypanosoma genus is different. [•] Polymorphism may be considered in designing drugs and vaccines for Chagas’ disease. [Copyright &y& Elsevier]

Abstract: Mechanistic target of rapamycin (mTOR) controls global translation of mRNA into protein by phosphorylating p70 S6 kinase (S6K) and eIF4E-binding protein-1. Akt and Rheb, a GTP-binding protein, regulate mTOR protein kinase activity. Molting in crustaceans is regulated by ecdysteroids synthesized by a pair of molting glands, or Y-organs (YOs), located in the cephalothorax. During premolt, the YOs hypertrophy and increase production of ecdysteroids. Rapamycin (1μM) inhibited ecdysteroid secretion in Carcinus maenas and Gecarcinus lateralis YOs in vitro, indicating that ecdysteroidogenesis requires mTOR-dependent protein synthesis. The effects of molting on the expression of four key mTOR signaling genes (mTOR, Akt, Rheb, and S6K) in the YO was investigated. Partial cDNAs encoding green crab (C. maenas) mTOR (4031bp), Akt (855bp), and S6K (918bp) were obtained from expressed sequence tags. Identity/similarity of the deduced amino acid sequence of the C. maenas cDNAs to human orthologs were 72%/81% for Cm-mTOR, 58%/73% for Cm-Akt, and 77%/88% for Cm-S6K. mTOR, Akt, S6K, and elongation factor 2 (EF2) in C. maenas and blackback land crab (G. lateralis) were expressed in all tissues examined. The two species differed in the effects of molting on gene expression in the YO. In G. lateralis, Gl-mTOR, Gl-Akt, and Gl-EF2 mRNA levels were increased during premolt. By contrast, molting had no effect on the expression of Cm-mTOR, Cm-Akt, Cm-S6K, Cm-Rheb, and Cm-EF2. These data suggest that YO activation during premolt involves up regulation of mTOR signaling genes in G. lateralis, but is not required in C. maenas. [Copyright &y& Elsevier]

The mammalian target of rapamycin (mTOR) signaling pathway is necessary for cellular protein synthesis regulation. Leucine was reported to stimulate muscle protein synthesis in mammalian embryos and neonates, but in higher animals (chickens) the effect of dietary leucine on mTOR signaling is unknown. Thus, we investigated the effects of dietary leucine and age on mRNA expression and phosphorylation of mTOR as well as its downstream targets, ribosomal protein S6 kinase (S6K1) and eukaryotic initiation factor 4E binding protein 1 (4E-BP1) in chick pectoral muscles. One hundred eighty newly hatched male chicks were randomly assigned to 1 of 3 dietary leucine treatment groups (1.43, 1.73, and 2.03% leucine) for 14 d, respectively. Each treatment group consisted of 6 cages with 10 chicks each. On d 3, 7, and 14, plasma insulin and leucine were measured and target gene expression and phosphorylation was assessed. Dietary leucine influenced plasma leucine but not insulin, and plasma leucine and insulin declined with chick age. The mTOR, S6K1, and 4E-BP1 mRNA expression and phosphorylation within chick pectoral muscles were upregulated with increased dietary leucine but downregulated with increased chick age. Thus, high dietary leucine activates target of rapamycin signaling pathways in skeletal muscle of neonatal chicks to stimulate muscle protein synthesis, and this pathway is attenuated with aging. [ABSTRACT FROM AUTHOR]

TOR kinase is a central coordinator of nutrient-dependent growth in eukaryotes. Maintaining optimal TOR signaling is critical for the normal development of organisms. In this study, we describe a negative feedback loop of TOR signaling helping in the adaptability of plants in changing environmental conditions. Using an interdisciplinary approach, we show that the plant-specific zinc finger protein FLZ8 acts as a regulator of TOR signaling in Arabidopsis. In sugar sufficiency, TOR-dependent and -independent histone modifications upregulate the expression of FLZ8. FLZ8 negatively regulates TOR signaling by promoting antagonistic SnRK1α1 signaling and bridging the interaction of SnRK1α1 with RAPTOR1B, a crucial accessory protein of TOR. This negative feedback loop moderates the TOR-growth signaling axis in the favorable condition and helps in the activation of stress signaling in unfavorable conditions, establishing its importance in the adaptability of plants. [Display omitted] • Negative feedback regulation of TOR signaling improves the fitness of plants • Sugar-TOR signaling promotes the level of FLZ8 through histone modifications • FLZ8 enhances SnRK1 signaling and bridges the SnRK1-RAPTOR1B association • Loss of FLZ8 leads to TOR hyperactivation and enhanced stress sensitivity Jamsheer K et al. show a negative feedback loop in the sugar-TOR signaling axis operating in favorable growth conditions through the land plant-specific zinc finger protein FLZ8. This regulation helps to maintain the basal level of stress-response machinery crucial for the adaptability of plants in sudden unfavorable conditions. [ABSTRACT FROM AUTHOR]

Abstract: Vitellogenin (Vg) synthesis, vitellogenesis, is an essential process for the development and reproduction of ticks. Our previous finding led to the hypothesis that target of rapamycin (TOR) pathway is important for vitellogenesis in the hard tick, Haemaphysalis longicornis. The TOR pathway controls cellular activity according to nutrient availability in eukaryotes. TOR, a member of the phosphatidylinositol 3-kinase family, is a central player in this pathway. Here, we present preliminary evidence that H. longicornis TOR (HlTOR) controls vitellogenesis via activation of S6 kinase (S6K) in the fat body. RNA interference (RNAi)-mediated gene silencing of HlTOR was undertaken to elucidate the involvement of HlTOR in the vitellogenesis of the tick. HlTOR-RNAi caused inhibition of S6K phosphorylation in the fat body. HlTOR-RNAi also altered not only the expression levels of GATA mRNA and protein but also the intracellular localisation of GATA in the fat body. The expression levels of Vg mRNA and protein in the fat body of HlTOR-RNAi ticks were significantly lower than those in control ticks. In the pre-ovipositional stage, the ovaries of control ticks had brown oocytes developing, but those of HlTOR-RNAi ticks were white and immature. The haemolymph colour indicated that the amount of Vg was lower in HlTOR-RNAi ticks than in the controls. Furthermore, rapamycin inhibited S6K phosphorylation and reduced the expression levels of Vg mRNA and protein in the fat bodies. Vg proteins were not detected in rapamycin-treated fat bodies in the presence of 20-hydroxyecdysone. These results suggest that HlTOR activity is critical for vitellogenesis stimulated by 20-hydroxyecdysone. [Copyright &y& Elsevier]

Abstract: Background: An important function of the fat body in adult female mosquitoes is the conversion of blood meal derived amino acids (AA) into massive amounts of yolk protein precursors. A highly efficient transport mechanism for AAs across the plasma membrane of the fat body trophocytes is essential in order to deliver building blocks for the rapid synthesis of large amounts of these proteins. This mechanism consists in part of AA transporter proteins from the solute carrier family. These transporters have dual function; they function as transporters and participate in the nutrient signal transduction pathway that is activated in the fat body after a blood meal. In this study we focused on the solute carrier 7 family (SLC7), a family of AA transporters present in all metazoans that includes members with strong substrate specificity for cationic AAs. Methodology/principal findings: We identified 11 putative SLC7 transporters in the genome sequence of Aedes aegypti. Phylogenetic analysis puts five of these in the cationic AA transporter subfamily (CAT) and six in the heterodimeric AA transporter (HAT) subfamily. All 11 A. aegypti SLC7 genes are expressed in adult females. Expression profiles are dynamic after a blood meal. We knocked down six fat body-expressed SLC7 transporters using RNAi and found that these ‘knockdowns’ reduced AA-induced TOR signaling. We also determined the effect these knockdowns had on the number of eggs deposited following a blood meal. Conclusions/significance: Our analysis stresses the importance of SLC7 transporters in TOR signaling pathway and mosquito reproduction. [Copyright &y& Elsevier]

Abstract: As a major intracellular source of reactive oxygen species (ROS), mitochondria are involved in aging and lifespan regulation. Using the yeast chronological aging model, researchers have identified conserved signaling pathways that affect lifespan by modulating mitochondrial functions. Caloric restriction and a genetic mimetic with reduced target of rapamycin signaling globally upregulate the mitochondrial proteome and respiratory functions. Recent discoveries support the notion that an altered mitochondrial proteome induces mitohormesis. Mitohormesis involves a variety of ROS during several growth stages and extends lifespan in yeast and other organisms. Here we recap recent advances in understanding of ROS as signals that decelerate chronological aging in yeast. We also discuss parallels between yeast and worm hypoxic signaling. In sum, this mini-review covers mitochondrial regulation by nutrient-sensing pathways and the complex underlying interactions of ROS, metabolic pathways, and chronological aging. [Copyright &y& Elsevier]

Abstract: The effects of dietary choline on growth, digestive and absorptive capacities, and target of rapamycin (TOR) and eIF4E-binding protein2 (4E-BP2) gene expression in muscle, hepatopancreas and intestine of juvenile Jian carp (Cyprinus carpio var. Jian) were assessed. A total of 1200 juvenile Jian carp with an average initial weight of 7.94±0.03g were fed six semi-purified diets containing 165 (unsupplemented control group), 310, 607, 896, 1167 and 1820mgcholinekg−1 diet for 65days. Specific growth rate (SGR), feed intake, feed efficiency, protein retention value, protein content and lipid content of fish carcasses were significantly improved by dietary choline supplementation; whereas, protein efficiency ratio and body ash content were not significantly different among dietary groups. Patterns of differences in intestine length, relative gut length, intestine weight, hepatopancreas protein content, intestinal folds height in three intestinal segments, trypsin and chymotrypsin activities in intestine and hepatopancreas, α-amylase and creatine kinase activities in intestine, Na+/K+-ATPase activity in distal intestine and relative expression of TOR gene in distal intestine and 4E-BP2 gene in muscle responded similar to SGR; whereas, the trends of hepatosomatic index, lipase activity in intestine and hepatopancreas, Na+/K+-ATPase activity in proximal intestine and mid intestine, TOR gene expression in muscle and hepatopancreas, and 4E-BP2 gene expression in proximal intestine, mid intestine and distal intestine were opposite. Alkaline phosphatase and γ-glutamyl transpeptidase activities in intestinal segments were not significantly different among dietary groups. These results indicated that dietary choline could improve fish growth, enhance digestive and absorptive ability and regulate TOR and 4E-BP2 gene expression in tissues. The dietary choline requirement of Jian carp estimated by the broken-line model based on SGR was 566mgcholinekg−1 diet in the form of choline chloride. [Copyright &y& Elsevier]

Abstract: Sirolimus is a member of a novel class of immunosuppressant drug that potently suppresses T cell proliferation and expansion by inhibition of the Target of Rapamycin Complex 1 (TORC1) protein kinase. Sirolimus also has anti-proliferative effects on intrinsic cells of the kidney, and increasing evidence suggests that it may have a therapeutic role in non-transplant renal diseases. In the normal kidney, sirolimus is considered to be non-nephrotoxic. In the diseased kidney, sirolimus may be beneficial or detrimental, depending on the type of renal injury. In polycystic kidney disease, TORC1 activation mediates renal tubular epithelial cell (TEC) proliferation and cyst growth in animals, and Phase III clinical trials are underway to determine the effect of sirolimus in attenuating disease progression in humans. In contrast, in acute kidney injury, sirolimus transiently impairs proximal TEC regeneration and delays renal recovery. In animal models of lupus nephritis and diabetic kidney disease, sirolimus prevents disease progression. However, the efficacy of sirolimus in human glomerulonephritis as well as in diabetic chronic kidney disease remains unclear, as it paradoxically exacerbates renal dysfunction when the baseline glomerular filtration rate is low (< 40 ml/min/1.73 m2) and there is heavy proteinuria (> 300 mg/day). This may, in part, be due to inhibition of compensatory glomerular capillary repair through the suppression of endothelial cell proliferation and angiogenic growth factor production by podocytes. Therefore, at present, polycystic kidney disease is the most promising therapeutic application for sirolimus in non-transplant renal diseases, and further studies are needed to clarify its role in other situations. [Copyright &y& Elsevier]

Abstract: Regulation of female mosquito feeding and reproduction plays a central role in their disease-vector competence. In this study we show that Anopheles gambiae mosquitoes engorged on albumin, amino acid and saline meals the same way as on blood, whereas sucrose evoked a typical plant nectar feeding response. Among the artificial diets, only the albumin-containing ones allowed follicular development. The target of rapamycin (TOR)/p70 S6 kinase (S6K) pathway has been identified as an essential nutrient-sensing tool controlling egg development in mosquitoes under the control of regulating inputs from the insulin pathway. We assayed the early response of TOR, S6K, tuberous sclerosis (TSC2), insulin receptor (INR) and two insulin-like peptides (ILPs) by quantitative real-time PCR assessment of mRNA levels and immunoblotting of phosphorylated active TOR and S6K in An. gambiae ovary and brain 3h after engorgement. We show that transcript levels of s6k and members of the insulin pathway are readily affected by nutrients (especially one ILP in the head) and that the TOR/S6K phosphorylation is able to react quickly to a meal to an extent which depends on the true nutritive value. [Copyright &y& Elsevier]

Abstract: In mosquitoes, yolk protein precursor (YPP) gene expression is activated after a blood meal through the synergistic action of a steroid hormone and the amino acid/target of rapamycin (TOR) signaling pathway in the fat body. We investigated the role of insulin signaling in the regulation of YPP gene expression. The presence of mosquito insulin receptor (InR) and the Protein kinase B (PKB/Akt) in the adult fat body of female mosquitoes was confirmed by means of the RNA interference (RNAi). Fat bodies stimulated with insulin were able to promote the phosphorylation of ribosomal S6 Kinase, a key protein of the TOR signaling pathway. Importantly, insulin in combination with 20-hydroxyecdysone activated transcription of the YPP gene vitellogenin (Vg), and this process was sensitive to the phosphoinositide-3 kinase (PI-3k) inhibitor LY294002 as well as the TOR inhibitor rapamycin. RNAi-mediated knockdown of the mosquito InR, Akt, and TOR inhibited insulin-induced Vg gene expression as well as S6 Kinase phosphorylation in in vitro fat body culture assays. [Copyright &y& Elsevier]

Abstract: Studies in cell-culture systems and in postmortem tissue from human disease have suggested a connection between cell-cycle activation and neurodegeneration. The fruit fly Drosophila melanogaster has recently emerged as a powerful model system in which to model neurodegenerative diseases. Here we review work in the fly that has begun to address some of the important questions regarding the relationship between cell-cycle activation and neurodegeneration in vivo, including recent data implicating cell-cycle activation as a downstream effector of tau-induced neurodegeneration. We suggest how powerful research tools in Drosophila might be utilized to approach fundamental questions that remain. [Copyright &y& Elsevier]

Abstract: Anautogeny is a successful reproductive strategy utilized by many mosquito species and other disease-transmitting arthropod vectors. Developing an understanding of the mechanisms underlying anautogeny in mosquitoes is very important because this reproductive strategy is the driving force behind the transmission of disease to millions of people. Information gained from mosquito studies may also be applicable to other blood feeding insect vectors. The conversion of protein from blood into yolk protein precursors for the developing oocytes is an essential part of the reproductive cycle, and understanding how this process is regulated could lead to safe, specific, and effective ways to block reproduction in blood feeding insects. Great gains have been made in elucidating the mechanisms that regulate vitellogenesis in mosquitoes, especially Ae. aegypti. However, a number of questions remain to be answered to make the picture more complete. In this review, we summarize what is currently known about the nutritional regulation of vitellogenesis in mosquitoes and the questions that remain to be answered about this important biological phenomenon. [Copyright &y& Elsevier]

Phosphonate analogues of phosphatidic acid (PA) were synthesized in which the bridging oxygen was replaced by an α-monofluoromethylene (–CHF–) or α-difluoromethylene (–CF2–) moiety using hydrolytic kinetic resolution (HKR) of a racemic epoxide as the key step. Since PA activates signaling in the mTOR (mammalian target of rapamycin) pathway, these metabolically stabilized PA analogues were evaluated in quiescent HEK 293 cells. Most of these analogues surpassed PA in activating S6 kinase, a downstream target of mTOR signaling. The unnatural (2R) analogues were more slightly active than the natural (2S) enantiomers for both the mono- and difluoromethylene phosphonates. [Copyright &y& Elsevier]

Growth of organisms and their constituent parts responds to both intrinsic and extrinsic cues during development: organisms of a given species generally grow at a predictable rate and to a specific body size, but individuals can modify this program during development in response to environmental conditions. Recent experiments, using gene knockouts and targeted overexpression, have revealed the central role of a signaling network controlled by the PI3K and TOR kinases in this regulation. These signaling molecules control growth by coordinately regulating a large number of cell biological processes. This review focuses on the cellular activities regulated by PI3K and TOR during development, and discusses how changes in different aspects of cellular metabolism may interact to regulate growth. [Copyright &y& Elsevier]

The purpose of this study was to estimate the effect of dietary protein and lipid levels on growth performance, feed utilization, body composition, liver metabolic enzymes activity and expression of insulin-like growth factor-1 (IGF-1) and target of rapamycin (TOR) of the northern whiting, Sillago sihama. A 56-day feeding trial was a completely randomized 4 × 3 factorial design and twelve diets were formulated containing four different protein levels (400, 450, 500 and 550 g/kg) and three different lipid levels (80, 100 and 120 g/kg). 1080 healthy fish (average wt. 0.83 ±0.01 g) were equally distributed in twelve treatments in triplicates with 30 fish per tank. At the end of the experiment, fish fed higher-protein diets (50%) resulted in significantly higher weight gain rate (WG), specific growth rate (SGR), and protein efficiency ratio (PER) compared to those fed the lower-protein treatments (40%). However, when the protein level in diet was 55%, WG began to decrease. The WG of fish fed the 12% lipid diets was significantly higher than that of fish fed the 8% lipid diets (P < 0.05). Also, higher dietary protein levels significantly reduced body moisture content, improved morphometrical indices and increased body lipid (P < 0.05). High-energy diets led to a decrease in the daily feed intake (DFI) of S. sihama. Based on WG, the optimal dietary protein requirement for the quadratic regression models was estimated to be 48.42% of dry matter when the lipid level was 10% and 48.53% for a diet containing 12% lipid. The activities of glutamic-pyruvic transaminase (GPT) and glutamic-oxalacetic transaminase (GOT) in liver increased with increasing dietary protein levels, and the activity of glutamate dehydrogenase (GDH) was significantly higher in the high-protein diets (50% and 55%) than that in the low-protein diets (40% and 45%) (P < 0.05). When lipid levels of the diet were higher than 10%, lipoprotein lipase (LPL) activities were significantly higher than that of the low-lipid groups (8% groups) (P < 0.05). Fatty acid synthase (FAS) activities were inhibited by the increasing lipid levels in diet. Dietary lipid levels significantly improved the expression level of insulin-like growth factor 1 (IGF-1) gene (P < 0.05). The relative expression of the target of rapamycin (TOR) gene in liver increased with dietary protein level at 45%–50%, however, it decreased at 55% of dietary protein levels and was significantly lower than that of the 50% group (P < 0.05). In conclusion, results of this study showed that the dietary protein requirements based on the growth of S. sihama were 48.42% (lipid level: 10%) and 48.53% (lipid level: 12%). • Based on WG, results of this study showed that the dietary protein requirements based on the growth of S. sihama were 48.42% (lipid level: 10%) and 48.53% (lipid level: 12%). • S. sihama had a limited ability to utilize dietary lipids. • High-energy diets lead to a decrease in dietary intake of S. sihama. • TOR gene expression level in liver was significantly affected by dietary protein levels. [ABSTRACT FROM AUTHOR]

• Low-N stress increases shoot-to-root auxin transport and increases auxin level in the root tip. • Higher auxin level in the root tip up-regulates cell wall acidification process which possibly accelerates cell elongation. • Higher auxin level in the root tip up-regulates TOR pathway which may accelerate cell division and/or cell elongation. Under low nitrogen (N) supply, an important adaption of the maize root system is to promote the root elongation so as to increase N uptake from a larger soil space. The underlying physiological mechanism is largely unknown. In the present study, two maize inbred lines (Ye478 and Wu312) were used to study the possible involvement of the auxin and target of rapamycin (TOR) pathway in low-N-induced root elongation. Compared to Wu312, primary root elongation of Ye478 was more sensitive to low nitrate supply. Correspondingly, more auxin was accumulated in the root tip, and more protons were secreted, increasing the acidity of the apoplast space. On the other hand, low-N-induced root elongation was greatly reduced when shoot-to-root auxin transport was inhibited by applying N-1-naphthylphthalamic acid (NPA) at the plant base or by pruning the top leaf where auxin is mostly synthesized. Furthermore, exogenous application of TOR inhibitor also eliminated the response of root elongation under low N. The content of TOR kinase and the expression of TOR pathway-related genes were significantly changed when shoot-to-root auxin transport was reduced by NPA treatment. Taken together, it is concluded that low-N stress increases shoot-to-root auxin transport which enhances root elongation via auxin-dependent acid growth and the auxin-regulated TOR pathway in maize. [ABSTRACT FROM AUTHOR]

The Target of Rapamycin (TOR) protein kinase plays a pivotal role in metabolism and gene expression, which enables cell proliferation, growth and development. Lipopolysaccharides (LPS) are a class of complex glycolipids present in the cell surface of Gram-negative bacteria and mediate plant-bacteria interactions. In this study, we examined whether LPS from Azospirillum brasilense Sp245 affect Arabidopsis thaliana growth via a mechanism involving TOR. A. thaliana plants were treated with LPS and plant growth and development were analyzed in mature plants. Morphological and molecular changes as well as TOR expression and activity were analyzed in root tissues. LPS increased total fresh weight, root length and TOR::GUS expression in the root meristem. Phosphorylation of S6k protein, a downstream target of TOR, increased following LPS treatment, which correlated with increased or decreased expression of CycB1;1::GUS protein upon treatment with LPS or TOR inhibitor AZD-8055, respectively. Long term LPS treatment further increased the rosette size as well as the number of stems and siliques per plant, indicating an overall phytostimulant effect for these signaling molecules. Taken together, the results suggest that A. brasilense LPS play probiotic roles in plants influencing TOR-mediated processes. [ABSTRACT FROM AUTHOR]

• Azospirillum brasilense Sp245 increases the expression of Target of Rapamycin (TOR) kinase in Arabidopsis. • Rhizobacterial-root interaction promotes phosphorylation of S6K. • The TOR inhibitor AZD-8055 antagonizes the plant probiotic effects of A. brasilense. • Bacterially-produced auxins influence TOR signaling and phytostimulation. Azospirillum brasilense colonizes plant roots and improves productivity, but the molecular mechanisms behind its phytostimulation properties remain mostly unknown. Here, we uncover an important role of TARGET OF RAPAMYCIN (TOR) signaling on the response of Arabidopsis thaliana to A. brasilense Sp245. The effect of the bacterium on TOR expression was analyzed in the transgenic line TOR/tor-1, which carries a translational fusion with the GUS reporter protein, and the activity of TOR was assayed thought the phosphorylation of its downstream signaling target S6K protein. Besides, the role of TOR on plant growth in inoculated plants was assessed using the ATP-competitive inhibitor AZD-8055. A decrease in growth of the primary root correlates with an improved branching and absorptive capacity via lateral root and root hair proliferation 6 days after transplant to different concentrations of the bacterium (103 or 105 CFU/mL). Bacterization increased the expression of TOR in shoot and root apexes and promoted phosphorylation of S6K 3 days after transplant. The TOR inhibitor AZD-8055 (1 μM) inhibited plant growth and cell division in root meristems and in lateral root primordia, interfering with the phytostimulation by A. brasilense. In addition, the role of auxin produced by the bacterium to stimulate TOR expression was explored. Noteworthy, the A. brasilense mutant FAJ009, impaired in auxin production, was unable to elicit TOR signaling to the level observed for the wild-type strain, showing the importance of this phyhormone to stimulate TOR signaling. Together, our findings establish an important role of TOR signaling for the probiotic traits elicited by A. brasilense in A. thaliana. [ABSTRACT FROM AUTHOR]

• SPC can be a good feed ingredient as swimming crab can tolerate up to 75% replacement. • Replacement of dietary fish meal with SPC will inhibit TOR pathway in hepatopancreas. • 51.49% replacement level with SPC is recommended for better PER. A 56-day feeding trial was conducted to evaluate the potential use of soy protein concentrate (SPC) as a partial replacement of fish meal in swimming crab Portunus trituberculatus. Four isonitrogenous and isolipidic diets (450 g/kg protein and 80 g/kg lipid) were formulated to contain graded levels of SPC, and fish meal was replaced with SPC at 25%, 50% and 75% level (SPC25, SPC50 and SPC75, respectively). The control diet (SPC0) contained fish meal, soybean meal and krill meal as the main protein sources. Lysine and methionine were added into SPC replacement diets to maintain the same concentrations as the control diet. Each diet was randomly assigned to triplicate groups of 45 juvenile swimming crabs (5.00 ± 0.23 g / crab) that were stocked in the rectangle plastic baskets. The results indicated that the weight gain (WG), special growth rate (SGR), feed efficiency (FE) and daily feed intake (DFI) were not significantly influenced by the dietary replacement of fish meal with SPC (P > 0.05). Crabs fed the SPC75 diet had lower protein efficiency ratio (PER) and molting frequencey (MF) than those fed the SPC50 diet(P < 0.05). The proximate compositions in whole body and muscle were not significantly influenced by the replacement of fish meal with SPC (P > 0.05), however, there was significant difference in the hepatopancreas moisture content (P < 0.05), and crabs fed the SPC0 diet had the highest lipid in hepatopancreas among all treatments (P < 0.05). Moreover, the essential amino acid (EAA), non-essential amino acid (NEAA) and total amino acid (TAA) contents of muscle significantly increased with the dietary replacement of fish meal with SPC levels increasing from 0 to 75% (P < 0.05). No significant differences in hemolymph enzyme activities and characteristics were observed among all treatments (P > 0.05). Crabs fed the SPC0 diet had higher amylase and lipase activities in hepatopancreas than those fed other diets. The hepatopancreas trypsin activity was not significantly influenced by the replacement of fish meal with SPC (P > 0.05). The hepatopancreas alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities increased when the dietary SPC levels increased from 0 to 25%, and then decreased significantly with the further increase of SPC replacement levels (P < 0.05). The relative expression of genes in target of rapamycin (TOR) pathway, crabs fed the SPC0 diet had higher relative expressions of tor, akt, s6k1, s6, 4ebp1, eif4e1a, eif4e2 and eif4e3 genes in hepatopancreas than those fed other diets (P < 0.05), moreover, there were no significant differences in gene expressions of TOR pathway among crabs fed the SPC25, SPC50 and SPC75 diets (P > 0.05). Based on the two slope broken-line regression analysis of PER against the dietary fish meal replacement with SPC levels, the optimum dietary replacement of fish meal with SPC was determined to be 51.49% for juvenile swimming crab. [ABSTRACT FROM AUTHOR]

• Silencing of target of rapamycin (TOR) in the pest insect Tribolium castaneum. • TcTOR -depletion affects growth rate but not food consumption. • Size of the appendages showed a significant reduction in TcTOR -depleted insects. • Size difference is attributed to a decrease in cell size and cell number. • Phenotype is correlated with a decrease in expression of TcCyclinE. The adult body size is species-specific and controlled by complex interactions between hormones and the IIS/TOR pathway. To analyze the role of target of rapamycin (TOR) in the growth and development of the insect, expression levels of TOR were silenced in the model and pest insect red flour beetle, Tribolium castaneum. Injection of dsRNA into the last larval instar decreased pupal mass and size, while the amount of food intake by the larvae was not affected. These results place TcTOR downstream of nutrition as a transducer for nutritional signals to increase larval growth. In addition, TcTOR -silencing notably decreased the size of the adult appendages. Analysis of the wings and elytra revealed a decrease in cell size and number of these appendages in the TcTOR -silenced insects. This reduction in size was correlated with a decrease of transcriptional levels of marker genes controlling the cell cycle. Altogether, these results suggest a pivotal role for TcTOR in integrating nutritional signals and regulation of body and appendages growth. [ABSTRACT FROM AUTHOR]

Abstract: For humans and other animals, gender has an influence not only on their physical attributes, but also on life span. In humans, females have a longer life span than males. The reasons for this are not entirely clear. The role of gender in the regulation of longevity may be linked to gender specific genetic differences, including the expression of sex hormone patterns and the changes in these patterns during an individual''s lifetime. In addition, the effect of sex hormones on other physiologic responses to environmental influences on cellular stress and oxidative damage may play a role in longevity. Gender can impact many disease states, including autoimmune diseases, and the factors that affect the development of autoimmune diseases and the regulation of longevity may share common mechanistic pathways. Other factors that may play a role include telomere and telomerase related differences, caloric restriction and changes in mitochondrial DNA. Inflammatory and regulatory pathways such as insulin/IGF signaling and Target of Rapamycin (TOR) signaling may also play a role in longevity and aging-related diseases such as Alzheimer''s. The role of gender differences in the regulation of these pathways or factors is not entirely clear. The role of X-chromosome inactivation in longevity has also yet to be fully elucidated. [Copyright &y& Elsevier]