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Abstract Plasma membrane H+-ATPase provides the driving force for light-induced stomatal opening. However, the mechanisms underlying the regulation of its activity remain unclear. Here, we show that the phosphorylation of two Thr residues in the C-terminal autoinhibitory domain is crucial for H+-ATPase activation and stomatal opening in Arabidopsis thaliana. Using phosphoproteome analysis, we show that blue light induces the phosphorylation of Thr-881 within the C-terminal region I, in addition to penultimate Thr-948 in AUTOINHIBITED H+-ATPASE 1 (AHA1). Based on site-directed mutagenesis experiments, phosphorylation of both Thr residues is essential for H+ pumping and stomatal opening in response to blue light. Thr-948 phosphorylation is a prerequisite for Thr-881 phosphorylation by blue light. Additionally, red light-driven guard cell photosynthesis induces Thr-881 phosphorylation, possibly contributing to red light-dependent stomatal opening. Our findings provide mechanistic insights into H+-ATPase activation that exploits the ion transport across the plasma membrane and light signalling network in guard cells.

Pexophagy plays a pivotal role in the selective removal of ROS-generating peroxisomes, which protects plants from oxidative damage during photosynthesis under high-intensity light.

Abstract Abdominal aortic aneurysm (AAA) is a lethal disease, but no beneficial therapeutic agents have been established to date. Previously, we found that AAA formation is suppressed in microRNA (miR)-33-deficient mice compared with wild-type mice. Mice have only one miR-33, but humans have two miR-33 s, miR-33a and miR-33b. The data so far strongly support that inhibiting miR-33a or miR-33b will be a new strategy to treat AAA. We produced two specific anti-microRNA oligonucleotides (AMOs) that may inhibit miR-33a and miR-33b, respectively. In vitro studies showed that the AMO against miR-33b was more effective; therefore, we examined the in vivo effects of this AMO in a calcium chloride (CaCl2)-induced AAA model in humanized miR-33b knock-in mice. In this model, AAA was clearly improved by application of anti-miR-33b. To further elucidate the mechanism, we evaluated AAA 1 week after CaCl2 administration to examine the effect of anti-miR-33b. Histological examination revealed that the number of MMP-9-positive macrophages and the level of MCP-1 in the aorta of mice treated with anti-miR-33b was significantly reduced, and the serum lipid profile was improved compared with mice treated with control oligonucleotides. These results support that inhibition of miR-33b is effective in the treatment for AAA.

Intranasal corticosteroids are effective medications against allergic rhinitis (AR). However, mucociliary clearance promptly eliminates these drugs from the nasal cavity and delays their onset of action. Therefore, a faster, longer-lasting therapeutic effect on the nasal mucosa is required to enhance the efficacy of AR management. Our previous study showed that polyarginine, a cell-penetrating peptide, can deliver cargo to nasal cells; moreover, polyarginine-mediated cell-nonspecific protein transduction into the nasal epithelium exhibited high transfection efficiency with minimal cytotoxicity. In this study, poly-arginine-fused forkhead box P3 (FOXP3) protein, the “master transcriptional regulator” of regulatory T cells (Tregs), was administered into the bilateral nasal cavities of the ovalbumin (OVA)-immunoglobulin E mouse model of AR. The effects of these proteins on AR following OVA administration were investigated using histopathological, nasal symptom, flow cytometry, and cytokine dot blot analyses. Polyarginine-mediated FOXP3 protein transduction induced Treg-like cell generation in the nasal epithelium and allergen tolerance. Overall, this study proposes FOXP3 activation-mediated Treg induction as a novel and potential therapeutic strategy for AR, providing a potential alternative to conventional intranasal drug application for nasal drug delivery.

Abstract This study aimed to verify the usefulness of the new layout at Center K after its transition from a facility for children with motional disabilities to a medical‐type facility for children with disabilities. We performed field research at the center before and after the transition in 2015 and 2016 respectively. We investigated the following four aspects: (i) Children's attributes in both types of facility, (ii) Children's usage rate of locations by day (weekday vs weekend), season, and unit, (iii) Nurses’ and nursing teachers’ nursing actions and usage rate of locations, and (iv) Behavioral changes in children who were transferred from the old to the new facility.

Infectious endocarditis is a life-threatening disease, and diagnostics are urgently needed to accurately diagnose this disease especially in the case of prosthetic valve endocarditis. We show here that maltohexaose conjugated to indocyanine green (MH-ICG) can detect Staphylococcus aureus (S. aureus) infection in a rat model of infective endocarditis. The affinity of MH-ICG to S. aureus was determined and had a Km and Vmax of 5.4 μM and 3.0 X 10-6 μmol/minutes/108 CFU, respectively. MH-ICG had no detectable toxicity to mammalian cells at concentrations as high as 100 μM. The in vivo efficiency of MH-ICG in rats was evaluated using a right heart endocarditis model, and the accumulation of MH-ICG in the bacterial vegetations was 2.5 ± 0.2 times higher than that in the control left ventricular wall. The biological half-life of MH-ICG in healthy rats was 14.0 ± 1.3 minutes, and approximately 50% of injected MH-ICG was excreted into the feces after 24 hours. These data demonstrate that MH-ICG was internalized by bacteria with high specificity and that MH-ICG specifically accumulated in bacterial vegetations in a rat model of endocarditis. These results demonstrate the potential efficacy of this agent in the detection of infective endocarditis.

Plasma membrane H+-ATPase provides the driving force for light-induced stomatal opening. However, the mechanisms underlying the regulation of its activity remain unclear. Here, we show that the phosphorylation of two Thr residues in the C-terminal autoinhibitory domain is crucial for H+-ATPase activation and stomatal opening in Arabidopsis thaliana. Using phosphoproteome analysis, we show that blue light induces the phosphorylation of Thr-881 within the C-terminal region I, in addition to penultimate Thr-948 in AUTOINHIBITED H+-ATPASE 1 (AHA1). Based on site-directed mutagenesis experiments, phosphorylation of both Thr residues is essential for H+ pumping and stomatal opening in response to blue light. Thr-948 phosphorylation is a prerequisite for Thr-881 phosphorylation by blue light. Additionally, red light-driven guard cell photosynthesis induces Thr-881 phosphorylation, possibly contributing to red light-dependent stomatal opening. Our findings provide mechanistic insights into H+-ATPase activation that exploits the ion transport across the plasma membrane and light signalling network in guard cells. Light-induced stomatal opening is crucial for photosynthesis. Here the authors show that blue light triggers phosphorylation of two Thr residues in the C-terminal autoinhibitory domain of plasma membrane H+-ATPase, thereby promoting stomatal opening. [ABSTRACT FROM AUTHOR]

Stomata open in response to low CO2 conditions in the light to maximise photosynthesis. Here, Hiyama et al. identify two kinases that promote stomatal opening by inhibiting S-type anion channels downstream of phototropin and HT1 thereby acting as a convergence point for blue light and CO2 signaling.

Intranasal corticosteroids are effective medications against allergic rhinitis (AR). However, mucociliary clearance promptly eliminates these drugs from the nasal cavity and delays their onset of action. Therefore, a faster, longer-lasting therapeutic effect on the nasal mucosa is required to enhance the efficacy of AR management. Our previous study showed that polyarginine, a cell-penetrating peptide, can deliver cargo to nasal cells; moreover, polyarginine-mediated cell-nonspecific protein transduction into the nasal epithelium exhibited high transfection efficiency with minimal cytotoxicity. In this study, poly-arginine-fused forkhead box P3 (FOXP3) protein, the "master transcriptional regulator" of regulatory T cells (Tregs), was administered into the bilateral nasal cavities of the ovalbumin (OVA)-immunoglobulin E mouse model of AR. The effects of these proteins on AR following OVA administration were investigated using histopathological, nasal symptom, flow cytometry, and cytokine dot blot analyses. Polyarginine-mediated FOXP3 protein transduction induced Treg-like cell generation in the nasal epithelium and allergen tolerance. Overall, this study proposes FOXP3 activation-mediated Treg induction as a novel and potential therapeutic strategy for AR, providing a potential alternative to conventional intranasal drug application for nasal drug delivery. [ABSTRACT FROM AUTHOR]

The proinflammatory cytokine interleukin-1 (IL-1) is produced by many types of cells, including immune cells in the periphery and glia and neurons in the brain. The type I IL-1 receptor (IL-1r1) is primarily responsible for transmitting the inflammatory effects of IL-1 and mediates several biological functions by binding to either IL-1α or IL-1β. IL-1β activation is associated with hippocampus-dependent memory tasks. Although IL-1β impairs spatial memory under certain pathophysiological conditions, IL-1β may be required for the normal physiological regulation of hippocampal plasticity and memory. In addition, brain IL-1β levels are thought to change in the hippocampus in an age-dependent manner. These findings suggest that IL-1β may have a beneficial, temporary effect on learning and memory in young mice, but the matter remains unclear. Therefore, we hypothesized that hippocampal IL-1β has a beneficial effect on spatial learning and memory in young mice via IL-1r1, which is diminished in adults. We investigated the performance of young (3-month-old) and adult (6-month-old) wild-type mice, IL-1β knockout mice (IL-1βko) and IL-1r1 knockout mice (IL-1r1ko) in learning a spatial memory task with a fixed platform in a water maze (WM) and measured the levels of IL-1β and IL-1α in the hippocampus and cortex of adult and young mice by using homogeneous time-resolved fluorescence (HTRF). Learning was significantly impaired in the training trials of the WM spatial memory task in young IL-1βko and IL-1r1ko mice but not in adult IL-1βko and IL-1r1ko mice. Moreover, young IL-1r1ko mice but not IL-1βko mice showed an impairment in long-term memory extinction, suggesting that IL-1α might facilitate memory extinction. In this study, the cytokine assay using HTRF did not indicate a higher expression of hippocampal IL-1 in young mice but cortical IL-1β and IL-1α were significantly increased in adult mice. We need to investigate the role of cortical IL-1 and the local IL-1 expression in the hippocampal neurons in the future.

Neurons interact closely with astrocytes via glutamate; this neuron-glia circuit may play a pivotal role in synaptic transmission. On the other hand, astrocytes contact vascular endothelial cells with their end-feet. It is becoming obvious that non-neuronal cells play a critical role in regulating the neuronal activity in the brain. We find that kainic acid (KA) administration induces the expression of microsomal prostaglandin E synthase-1 (mPGES-1) in venous endothelial cells and the prostaglandin E2 (PGE2) receptor prostaglandin E receptor (EP)-3 on astrocytes. Endothelial mPGES-1 exacerbates KA-induced neuronal damage in in vivo experiments. In in vitro experiments, mPGES-1 produces PGE2, which enhances astrocytic Ca2+ levels via the EP3 receptor and increases Ca2+-dependent glutamate release, thus aggravating neuronal injury. This novel endothelium-astrocyte-neuron signaling pathway may be crucial for driving neuronal damage after repetitive seizures and could be a new therapeutic target for epilepsy and other brain disorders.

The circadian clock allows plants to anticipate and adapt to periodic environmental changes. Organ- and tissue-specific properties of the circadian clock and shoot-to-root circadian signaling have been reported. While this long-distance signaling is thought to coordinate physiological functions across tissues, little is known about the feedback regulation of the root clock on the shoot clock in the hierarchical circadian network. Here, we show that the plant circadian clock conveys circadian information between shoots and roots through sucrose and K+. We also demonstrate that K+ transport from roots suppresses the variance of period length in shoots and then improves the accuracy of the shoot circadian clock. Sucrose measurements and qPCR showed that root sucrose accumulation was regulated by the circadian clock. Furthermore, root circadian clock genes, including PSEUDO-RESPONSE REGULATOR7 (PRR7), were regulated by sucrose, suggesting the involvement of sucrose from the shoot in the regulation of root clock gene expression. Therefore, we performed time-series measurements of xylem sap and micrografting experiments using prr7 mutants and showed that root PRR7 regulates K+ transport and suppresses variance of period length in the shoot. Our modeling analysis supports the idea that root-to-shoot signaling contributes to the precision of the shoot circadian clock. We performed micrografting experiments that illustrated how root PRR7 plays key roles in maintaining the accuracy of shoot circadian rhythms. We thus present a novel directional signaling pathway for circadian information from roots to shoots and propose that plants modulate physiological events in a timely manner through various timekeeping mechanisms. [ABSTRACT FROM AUTHOR]

This study introduces the concept of computational salience to explain the discriminatory efficacy of decision points, which in turn may have applications to providing real-time assistance to users of navigational aids. This research compared algorithms for calculating the computational salience of decision points and validated the results via three methods: high-salience decision points were used to classify wayfinders; salience scores were used to weight a conditional probabilistic scoring function for real-time wayfinder performance classification; and salience scores were correlated with wayfinding-performance metrics. As an exploratory step to linking computational and cognitive salience, a photograph-recognition experiment was conducted. Results reveal a distinction between algorithms useful for determining computational and cognitive saliences. For computational salience, information about the structural integration of decision points is effective, while information about the probability of decision-point traversal shows promise for determining cognitive salience. Limitations from only using structural information and motivations for future work that include non-structural information are elicited.

Microsomal prostaglandin E synthetase-1 (mPGES-1) is an inducible terminal enzyme for the production of prostaglandin E2 (PGE2). In experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, mPGES-1 is induced in vascular endothelial cells (VECs) around inflammatory foci and facilitates inflammation, demyelination, and paralysis. Therefore, we investigated the role of CD31-positive VECs in mPGES-1-mediated EAE aggravation using immunohistochemical analysis and imaging of wild-type (wt) and mPGES-1-deficient (mPGES-1−/−) mice. We demonstrated that EAE induction facilitated vascularity in inflammatory lesions in the spinal cord, and this was significantly higher in wt mice than in mPGES-1−/− mice. In addition, endothelial interleukin-1β (IL-1β) production was significantly higher in wt mice than in mPGES-1−/− mice. Moreover, endothelial PGE2 receptors (E-prostanoid (EP) receptors EP1⁻4) were expressed after EAE induction, and IL-1β was induced in EP receptor-positive VECs. Furthermore, IL-1 receptor 1 expression on VECs was increased upon EAE induction. Thus, increased vascularity is one mechanism involved in EAE aggravation induced by mPGES-1. Furthermore, mPGES-1 facilitated the autocrine function of VECs upon EP receptor induction and IL-1β production, modulating mPGES-1 induction in EAE.

Microsomal prostaglandin synthetase-1 (mPGES-1) is an inducible terminal enzyme that produces prostaglandin E2 (PGE2). In our previous study, we investigated the role of mPGES-1 in the inflammation and demyelination observed in experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis, using mPGES-1-deficient (mPGES-1−/−) and wild-type (wt) mice. We found that mPGES-1 facilitated inflammation, demyelination, and paralysis and was induced in vascular endothelial cells and macrophages and microglia around inflammatory foci. Here, we investigated the role of interleukin-1β (IL-1β) in the intercellular mechanism stimulated by mPGES-1 in EAE spinal cords in the presence of inflammation. We found that the area invaded by CD4-positive (CD4+) T cells was extensive, and that PGE2 receptors EP1–4 were more induced in activated CD4+ T cells of wt mice than in those of mPGES-1−/− mice. Moreover, IL-1β and IL-1 receptor 1 (IL-1r1) were produced by 65% and 48% of CD4+ T cells in wt mice and by 44% and 27% of CD4+ T cells in mPGES-1−/− mice. Furthermore, interleukin-17 (IL-17) was released from the activated CD4+ T cells. Therefore, mPGES-1 stimulates an intercellular interaction between CD4+ T cells by upregulating the autocrine function of IL-1β in activated CD4+ T cells, which release IL-17 to facilitate axonal and myelin damage in EAE mice.

Reactive oxygen species (ROS) play a central role in plant responses to biotic and abiotic stresses. ROS stimulate stomatal closure by inhibiting blue light (BL)-dependent stomatal opening under diverse stresses in the daytime. However, the stomatal opening inhibition mechanism by ROS remains unclear. In this study, we aimed to examine the impact of reactive carbonyl species (RCS), lipid peroxidation products generated by ROS, on BL signaling in guard cells. Application of RCS, such as acrolein and 4-hydroxy-(E)-2-nonenal (HNE), inhibited BL-dependent stomatal opening in the epidermis of Arabidopsis thaliana. Acrolein also inhibited H+ pumping and the plasma membrane H+-ATPase phosphorylation in response to BL. However, acrolein did not inhibit BL-dependent autophosphorylation of phototropins and the phosphorylation of BLUE LIGHT SIGNALING1 (BLUS1). Similarly, acrolein affected neither the kinase activity of BLUS1 nor the phosphatase activity of protein phosphatase 1, a positive regulator of BL signaling. However, acrolein inhibited fusicoccin-dependent phosphorylation of H+-ATPase and stomatal opening. Furthermore, carnosine, an RCS scavenger, partially alleviated the abscisic-acid- and hydrogen-peroxide-induced inhibition of BL-dependent stomatal opening. Altogether, these findings suggest that RCS inhibit BL signaling, especially H+-ATPase activation, and play a key role in the crosstalk between BL and ROS signaling pathways in guard cells. [ABSTRACT FROM AUTHOR]