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Glutathione (GSH) functions as a major sulfur repository and hence occupies an important position in primary sulfur metabolism. GSH degradation results in sulfur reallocation and is believed to be carried out mainly by γ-glutamyl cyclotransferases (GGCT2;1, GGCT2;2, and GGCT2;3), which, however, do not fully explain the rapid GSH turnover. Here, we discovered that γ-glutamyl peptidase 1 (GGP1) contributes to GSH degradation through a yeast complementation assay. Recombinant proteins of GGP1, as well as GGP3, showed high degradation activity of GSH, but not of oxidized glutathione (GSSG), in vitro. Notably, the GGP1 transcripts were highly abundant in rosette leaves, in agreement with the ggp1 mutants constantly accumulating more GSH regardless of nutritional conditions. Given the lower energy requirements of the GGP- than the GGCT-mediated pathway, the GGP-mediated pathway could be a more efficient route for GSH degradation than the GGCT-mediated pathway. Therefore, we propose a model wherein cytosolic GSH is degraded chiefly by GGP1 and likely also by GGP3. Another noteworthy fact is that GGPs are known to process GSH conjugates in glucosinolate and camalexin synthesis; indeed, we confirmed that the ggp1 mutant contained higher levels of O-acetyl-l-Ser, a signaling molecule for sulfur starvation, and lower levels of glucosinolates and their degradation products. The predicted structure of GGP1 further provided a rationale for this hypothesis. In conclusion, we suggest that GGP1 and possibly GGP3 play vital roles in both primary and secondary sulfur metabolism.

Glucosinolates (GSL) are sulfur (S)-rich specialized metabolites produced by plants of the Brassicales order. Our previous study found that in Arabidopsis seedlings, S deficiency (−S) promoted GSL catabolism by activating two ß-glucosidases (BGLU), BGLU28 and BGLU30. The induced GSL catabolism was a survival strategy for seedlings grown under −S, because S released from GSL was reincorporated into primary S metabolites which are essential for plant growth. However, as GSL profile in plants vary among growth stages and organs, we set out to test a potential contribution of BGLU28/30-dependent GSL catabolism at the reproductive growth stage. Thus, in this study, we assessed growth, metabolic, and transcriptional phenotypes of maturebglu28/30double mutants grown under different S conditions. Our results showed that compared to wild-type plants grown under −S, maturebglu28/30mutants displayed impaired growth and accumulated increased levels of GSL in their mature seeds, siliques, flowers, and rosette leaves of before bolting plants. In contrast, the levels of primary S-containing metabolites, glutathione and cysteine, were decreased in mature seeds. Furthermore, the transport of GSL from rosette leaves to the reproductive organs was stimulated in thebglu28/30mutants under −S. Transcriptome analysis revealed that genes related to other biological processes, such as phytohormone signaling and plant response to heat, responded differentially to −S in thebglu28/30mutants. Altogether, these findings broadened our understanding of the roles of BGLU28/30-dependent GSL catabolism in plant adaptation to nutrient stress.One-sentence summaryDisruption of glucosinolate catabolic genes,BGLU28andBGLU30, in sulfur-starved matureArabidopsisimpaired growth, affected glucosinolate distribution, and altered transcriptional profiles.

Rapeseed contains high levels of glucosinolates (GSLs), playing pivotal roles in defense against herbivores and pests. As their presence in rapeseed reduces the value of the meal for animal feeding, intensive efforts to reduce them produced low-seed GSL cultivars. However, there is no such variety suitable for the south part of Japan. Here, we tested the effects of cold oxygen plasma (oxygen CP) on seed germination and GSL and lipid content, in 3 rapeseed cultivars. According to the cultivars, oxygen CP slightly stimulated seed germination and modified the GSL levels, and decreased GSL levels in Kizakinonatane but increased those in Nanashikibu. In contrast, it negligibly affected the lipid content and composition in the 3 cultivars. Thus, oxygen CP modulated seed GSL levels without affecting seed viability and lipid content. Future optimization of this technique may help optimize rapeseed GSL content without plant breeding.

Background: The number of young Japanese Brazilians, who are return migrants with Japanese ancestral roots, is increasing rapidly in Japan. However, the characteristics of their mental health and the relation between mental health and a complex ethnic identity remains unclear. Methods: This cross-sectional study compared 25 Japanese–Brazilian high school students with 62 Japanese high school students living in the same area. Research using self-report questionnaires on mental health, help-seeking behavior tendencies, and ethnic identity was conducted. The Japanese–Brazilian group was also divided into high and low ethnic identity groups, and their mental health conditions were compared. Results: The Japanese–Brazilian group had significantly poorer mental health conditions and lower ethnic identities than the Japanese group and were less likely to seek help from family members and close relatives. Among the Japanese Brazilians, those with low ethnic identity had significantly poorer mental health than those with high ethnic identity. Conclusions: Young Japanese Brazilians may face conflicts of ethnic identity that can disturb their mental health. To build an inclusive society, the establishment of community services to support mental health and to help return migrants develop their ethnic identity is essential.

Systemic acquired resistance (SAR) is a potent innate immunity system in plants that is induced through the salicylic acid (SA)-mediated signaling pathway. Here, we characterized 3-chloro-1-methyl-1H-pyrazole-5-carboxylic acid (CMPA) as an effective SAR inducer in Arabidopsis. The soil drench application of CMPA enhanced a broad range of disease resistance against the bacterial pathogen Pseudomonas syringae and fungal pathogens Colletotrichum higginsianum and Botrytis cinerea in Arabidopsis, whereas CMPA did not show antibacterial activity. Foliar spraying with CMPA induced the expression of SA-responsible genes such as PR1, PR2 and PR5. The effects of CMPA on resistance against the bacterial pathogen and the expression of PR genes were observed in the SA biosynthesis mutant, however, while they were not observed in the SA-receptor-deficient npr1 mutant. Thus, these findings indicate that CMPA induces SAR by triggering the downstream signaling of SA biosynthesis in the SA-mediated signaling pathway.

A newly identified chemical, 4-{3-[(3,5-dichloro-2-hydroxybenzylidene)amino]propyl}-4,5-dihydro-1H-pyrazol-5-one (BAPP) was characterized as a plant immunity activator. BAPP enhanced disease resistance in rice against rice blast disease and expression of a defense-related gene without growth inhibition. Moreover, BAPP was able to enhance disease resistance in dicotyledonous tomato and Arabidopsis plants against bacterial pathogen without growth inhibition, suggesting that BAPP could be a candidate as an effective plant activator. Analysis using Arabidopsis sid2-1 and npr1-2 mutants suggested that BAPP induced systemic acquired resistance (SAR) by stimulating between salicylic acid biosynthesis and NPR1, the SA receptor protein, in the SAR signaling pathway.

Glucosinolates (GSLs) are secondary metabolites that play important roles in plant defense and are suggested to act as storage compounds. Despite their important roles, metabolic dynamics of GSLs under various growth conditions remain poorly understood. To determine how light conditions influence the levels of different GSLs and their distribution in Arabidopsis leaves, we visualized the GSLs under different light conditions using matrix-assisted laser desorption/ionization mass spectrometry imaging. We observed the unique distribution patterns of each GSL in the inner regions of leaves and marked decreases under darkness, indicating light conditions influenced GSL metabolism. GSLs are hydrolyzed by a group of ß-glucosidase (BGLU) called myrosinase. Previous transcriptome data for GSL metabolism under light and dark conditions have revealed the highly induced expression of BGLU30, one of the putative myrosinases, which is also annotated as Dark INducible2, under darkness. Impairment of the darkness-induced GSL decrease in the disruption mutants of BGLU30, bglu30, indicated that BGLU30 mediated GSL hydrolysis under darkness. Based on the GSL profiles in the wild-type and bglu30 leaves under both conditions, short-chain GSLs were potentially preferable substrates for BGLU30. Our findings provide an effective way of visualizing GSL distribution in plants and highlighted the carbon storage GSL function.

Sulfur (S) is an essential element for plants, and S deficiency causes severe growth retardation. Although the catabolic process of glucosinolates (GSLs), the major S-containing metabolites specific to Brassicales including Arabidopsis, has been recognized as one of the S deficiency (−S) responses in plants, the physiological function of this metabolic process is not clear. Two β-glucosidases (BGLUs), BGLU28 and BGLU30, are assumed to be responsible for this catabolic process as their transcript levels were highly upregulated by −S. To clarify the physiological function of BGLU28 and BGLU30 and their roles in GSL catabolism, we analyzed the accumulation of GSLs and other S-containing compounds in the single and double mutant lines of BGLU28 and BGLU30 and in wild-type plants under different S conditions. GSL levels were highly increased, while the levels of sulfate, cysteine, glutathione and protein were decreased in the double mutant line of BGLU28 and BGLU30 (bglu28/30) under −S. Furthermore, transcript level of Sulfate Transporter1;2, the main contributor of sulfate uptake from the environment, was increased in bglu28/30 mutants under −S. With these metabolic and transcriptional changes, bglu28/30 mutants displayed obvious growth retardation under −S. Overall, our results indicate that BGLU28 and BGLU30 are required for −S-induced GSL catabolism and contribute to sustained plant growth under −S by recycling sulfate to primary S metabolism.

Strigolactones are low-molecular-weight phytohormones that play several roles in plants, such as regulation of shoot branching and interactions with arbuscular mycorrhizal fungi and parasitic weeds. Recently, strigolactones have been shown to be involved in plant responses to abiotic and biotic stress conditions. Herein, we analyzed the effects of strigolactones on systemic acquired resistance induced through salicylic acid-mediated signaling. We observed that the systemic acquired resistance inducer enhanced disease resistance in strigolactone-signaling and biosynthesis-deficient mutants. However, the amount of endogenous salicylic acid and the expression levels of salicylic acid-responsive genes were lower in strigolactone signaling-deficient

SummaryOrganic sulfur is stored as glutathione (GSH) in plants. In Arabidopsis, γ-glutamyl cyclotransferases (GGCT2;1, GGCT2;2, and GGCT2;3) degrade cytosolic GSH, but they do not fully explain the rapid GSH turnover. Here, we demonstrate that γ-glutamyl peptidases, GGP1 and GGP3, play a substantial role in degrading GSH in the cytosol.We conducted yeast complementation assay and activity assay of recombinant proteins to identify the novel GSH degradation enzymes. The expression patterns were investigated by RT-qPCR. GSH concentrations in the mutants were also analyzed.GGP1 complemented the yeast phenotype. Recombinant GGP1 and GGP3 showed reasonable Km values considering cytosolic GSH concentration, and their activity was comparable to that of GGCTs. The GGP1 transcript was highly abundant in mature organs such as rosette leaves. The expression of GGCT2;1 was conspicuously enhanced under sulfur deficiency. GSH concentration was higher in ggp1 knockout mutants regardless of nutritional conditions; the concentration was higher in ggct2;1 knockout mutants under sulfur-deficient conditions.We propose a model wherein cytosolic GSH is degraded fundamentally by GGP1. The degradation is accelerated by GGCT2;1 under sulfur deficiency. Given the energy cost throughout the reactions, GGPs could render a more efficient route for GSH degradation than GGCTs.

High-salinity stress represses plant growth by inhibiting various metabolic processes. In contrast to the well-studied mechanisms mediating tolerance to high levels of salt, the effects of low levels of salts have not been well studied. In this study, we examined the growth of Arabidopsis thaliana plants under different NaCl concentrations. Interestingly, both shoot and root biomass increased in the presence of 5 mM NaCl, whereas more than 10 mM NaCl decreased plant biomass. To clarify the biological mechanism by which a low level of NaCl stimulated plant growth, we analyzed element accumulation in plants grown under different NaCl concentrations. In addition to the Na and Cl contents, C, S, Zn, and Cu contents were increased under 5 mM NaCl in shoots, this was not observed at higher NaCl concentrations. Adverse effects of high salinity, such as decreased levels of nitrate, phosphate, sulfate, and some cations, did not occur in the presence of 5 mM NaCl. An increase in C was possibly attributed to increased photosynthesis supported by Cl, Zn, and Cu, which also increased in shoots after NaCl application. Salt stress-responsive gene expression was enhanced under 20 mM NaCl but not at lower doses. Among the S metabolites analyzed, cysteine (Cys) was increased by 5 mM NaCl, suggesting that S assimilation was promoted by this dose of NaCl. These results indicate the usefulness of NaCl for plant growth stimulation.

Strigolactones are low-molecular-weight phytohormones that play several roles in plants, such as regulation of shoot branching and interactions with arbuscular mycorrhizal fungi and parasitic weeds. Recently, strigolactones have been shown to be involved in plant responses to abiotic and biotic stress conditions. Herein, we analyzed the effects of strigolactones on systemic acquired resistance induced through salicylic acid-mediated signaling. We observed that the systemic acquired resistance inducer enhanced disease resistance in strigolactone-signaling and biosynthesis-deficient mutants. However, the amount of endogenous salicylic acid and the expression levels of salicylic acid-responsive genes were lower in strigolactone signaling-deficient max2 mutants than in wildtype plants. In both the wildtype and strigolactone biosynthesis-deficient mutants, the strigolactone analog GR24 enhanced disease resistance, whereas treatment with a strigolactone biosynthesis inhibitor suppressed disease resistance in the wildtype. Before inoculation of wildtype plants with pathogenic bacteria, treatment with GR24 did not induce defense-related genes; however, salicylic acid-responsive defense genes were rapidly induced after pathogenic infection. These findings suggest that strigolactones have a priming effect on Arabidopsis thaliana by inducing salicylic acid-mediated disease resistance.

Background International immigration to Japan, where homogeneous ethnicity is a population characteristic, has been growing. Although immigration is recognised as a risk factor for multiple mental-health related issues, there are few regional reports on foreign nationals accessing the psychiatric services in Japan. We aimed to reveal their current status and provide information to develop an optimal service system. Methods A multicentre retrospective document review research was conducted. The subjects were foreign nationals who resided in Japan and presented at the psychiatry departments in three core regional hospitals in the Keihin region, which faces Tokyo Bay and is well known to include the largest traditional industrial zone in Japan, over a period of 3 years. We investigated the patients’ demographic and clinical information including country/region of origin, spoken language, use of a medical interpreter, pathway to hospitals and outcome. Results The percentage of foreign patients among all patients (1.4%) was quite low. Their age distribution (45.8 years on average) was dissociated from the age distribution of foreign nationals who resided in Japan. Regarding the country/region of origin, China (35.1%) was the most common country, followed by the Philippines, Korea and Brazil. Several subjects (22.9%) could not speak Japanese; therefore, interpretation was required by family members/friends (17.1%) or a professional interpreter (5.4%). Neurotic and stress-related disorders were the most common diagnosis (24.4%). The proportion of psychoactive substance use was higher than that for Japanese national data as immigrants are known to be at risk for it. Conclusions The results suggest that foreign nationals who reside in Japan are less likely to contact appropriate services for mental illness, especially young people at relatively high risk of mental illness do not access services. Furthermore, lack of medical interpreters may impede the mental health conditions of foreign nationals. The development of a community-based integrated care system accessible to foreign nationals seems to be indispensable.

Background: International immigration to Japan, where homogeneous ethnicity is a population characteristic, has been growing. Although immigration is recognized as a risk factor for multiple mental-health related issues, there are few regional reports on foreign residents who visit a hospital for mental health problems in Japan. We aimed to examine such patients’ characteristics.Methods: A multicenter retrospective study using medical records was conducted. The subjects were foreign patients who presented at the psychiatry departments in three core regional hospitals in the Keihin region, which faces Tokyo Bay and is well known to include the largest traditional industrial zone in Japan, over a period of three years. We investigated the patients’ demographic and clinical information including country/region of origin, spoken language, use of a medical interpreter, pathway to hospitals, and outcome.Results: The percentage of foreign individuals among all patients was 1.4% (205/14511). The mean age of the foreign patients was 45.8 years, and the sex ratio was 1:1.9 (men: women). Regarding the country/region of origin, China (35.1%) was the most common country, followed by the Philippines (18.5%), Korea (16.1%), and Brazil (4.9%). Several subjects (22.9%) could not speak Japanese; therefore, interpretation was required by family members/friends (17.1%) or a professional interpreter (5.4%). Neurotic disorder (ICD-10 code: F4) was the most common diagnosis (24.4%).Conclusions: The percentage of foreign patients seeking psychiatric treatment (1.4%) was relatively low, compared with the percentage of foreign residents living in the Keihin region (4.4%). The age distribution of foreign residents who visited psychiatric department was dissociated from the age distribution of foreign residents in Japan. This suggests that young foreign residents with a relatively high risk for mental illness are not accessing appropriate services. The development of a community-based integrated care system accessible to foreign residents seems to be indispensable.

Recent studies have shown various metabolic and transcriptomic interactions between sulfur (S) and phosphorus (P) in plants. However, most studies have focused on the effects of phosphate (Pi) availability and P signaling pathways on S homeostasis, whereas the effects of S availability on P homeostasis remain largely unknown. In this study, we investigated the interactions between S and P from the perspective of S availability. We investigated the effects of S availability on Pi uptake, transport, and accumulation in Arabidopsis thaliana grown under sulfur sufficiency (+S) and deficiency (−S). Total P in shoots was significantly increased under −S owing to higher Pi accumulation. This accumulation was facilitated by increased Pi uptake under −S. In addition, −S increased root-to-shoot Pi transport, which was indicated by the increased Pi levels in xylem sap under −S. The −S-increased Pi level in the xylem sap was diminished in the disruption lines of PHT1;9 and PHO1, which are involved in root-to-shoot Pi transport. Our findings indicate a new aspect of the interaction between S and P by listing the increased Pi accumulation as part of −S responses and by highlighting the effects of −S on Pi uptake, transport, and homeostasis.

Sulfur (S) assimilation, which is initiated by sulfate uptake, generates cysteine, the substrate for glutathione (GSH) and phytochelatin (PC) synthesis. GSH and PC contribute to cadmium (Cd) detoxification by capturing it for sequestration. Although Cd exposure is known to induce the expression of S-assimilating enzyme genes, including sulfate transporters (SULTRs), mechanisms of their transcriptional regulation are not well understood. Transcription factor SLIM1 controls transcriptional changes during S deficiency (&minus, S) in Arabidopsis thaliana. We examined the potential involvement of SLIM1 in inducing the S assimilation pathway and PC accumulation. Cd treatment reduced the shoot fresh weight in the sulfur limitation1 (slim1) mutant but not in the parental line (1, 2PGN). Cd-induced increases of sulfate uptake and SULTR1, 2 expressions were diminished in the slim1 mutant, suggesting that SLIM1 is involved in inducing sulfate uptake during Cd exposure. The GSH and PC levels were lower in slim1 than in the parental line, indicating that SLIM1 was required for increasing PC during Cd treatment. Hence, SLIM1 indirectly contributes to Cd tolerance of plants by inducing &minus, S responses in the cell caused by depleting the GSH pool, which is consumed by enhanced PC synthesis and sequestration to the vacuole.

Highlights / • Multiple mechanisms to up-regulate sulfate uptake in low sulfur environment. / • Sulfate transporters act as sulfate receptors. / • Contribution of SLIM1 transcription factor to controlling metabolic flow of sulfur in response to sulfur deficiency. / • Sulfur deficiency-induced repression of aliphatic glucosinolates biosynthesis. / • Catabolism of organic sulfur compounds accelerated under sulfur deficiency. /, Plants assimilate inorganic sulfate into various organic sulfur (S) compounds, which contributes to the global sulfur cycle in the environment as well as the nutritional supply of this essential element to animals. Plants, to sustain their lives, adapt the flow of their S metabolism to respond to external S status by activating S assimilation and catabolism of stored S compounds, and by repressing the synthesis of secondary S metabolites like glucosinolates. The molecular mechanism of this response has been gradually revealed, including the discovery of several regulatory proteins and enzymes involved in S deficiency responses. Recent progress in this research area and the remaining issues are reviewed here.

Plants increase sulfate uptake activity under sulfur deficiency (-S). In Arabidopsis, SULTR1;2 is the major high-affinity sulfate transporter induced in epidermis and cortex of roots for mediating sulfate uptake under -S. Though it is known that transcript levels of SULTR1;2 increase under -S largely due to the function of 5'-upstream region, contributions of 5'-non-transcribed flanking region and 5'-untranslated region (UTR) to transcriptional and post-transcriptional regulations have not yet been individually verified. To investigate the roles of 5'UTR of SULTR1;2 in -S responses, transcript levels and activities of firefly luciferase (Luc) were analyzed in transgenic plants expressing Luc under the control of the 2,160-bp long 5'-upstream region of SULTR1;2 with (PL2160) or without (PL2160ΔUTR) the 154-bp 5'UTR. Both transgenic plants expressed similar levels of Luc mRNAs that showed significant accumulations under -S relative to +S regardless of presence of the 5'UTR. In contrast, Luc activities were detected only in PL2160 plants, suggesting presence of 5'UTR of SULTR1;2 being necessary for translational initiation while its absence impairing translation of functional Luc protein in PL2160ΔUTR. These results indicate an essential role of the 5'-non-transcribed flanking region of SULTR1;2 at positions -2160 to -155 in -S-responsive transcriptional regulation.

Root hairs often contribute to nutrient uptake from environments, but the contribution varies among nutrients. In Arabidopsis, two high-affinity sulfate transporters, SULTR1, 1 and SULTR1, 2, are responsible for sulfate uptake by roots. Their increased expression under sulfur deficiency (&minus, S) stimulates sulfate uptake. Inspired by the higher and lower expression, respectively, of SULTR1, 1 in mutants with more (werwolf [wer]) and fewer (caprice [cpc]) root hairs, we examined the contribution of root hairs to sulfate uptake. Sulfate uptake rates were similar among plant lines under both sulfur sufficiency (+S) and &minus, S. Under &minus, S, the expression of SULTR1, 2 was negatively correlated with the number of root hairs. These results suggest that both &minus, S-induced SULTR expression and sulfate uptake rates were independent of the number of root hairs. In addition, we observed (1) a negative correlation between primary root lengths and number of root hairs and (2) a greater number of root hairs under &minus, S than under +S. These observations suggested that under both +S and &minus, S, sulfate uptake was influenced by the root biomass rather than the number of root hairs.

Aim Burnout is a common feature among healthcare professionals; however, little systematic research exists on burnout among nurses who are raising children. The burnout-related factors among female nurses with children under the age of 3 years were identified in order to ascertain potential burnout prevention methods. Methods In total, 1681 nurses with children who worked at nine city hospitals in Kanagawa Prefecture, Japan, were sent the Maslach Burnout Inventory–Human Services Survey; 1173 nurses responded in June 2014. They were divided according to their sex and children's ages. A data analysis was undertaken for those female nurses with children who were aged under 3 years who provided valid responses (n = 158). Results A number of factors related to burnout in female nurses with children aged under 3 years was found via a multiple regression analysis: irritation at being unable to attend to their own affairs, over 4–6 h of overtime work per week, having a child aged under 3 years as the first or second child, little sense of work fulfillment, using a childcare facility outside the workplace, dissatisfaction with their salary, feeling ill-qualified as a parent, and a sense of inadequate support. Conclusions Child care occurs during a limited period and appropriate support is needed. A workplace environment with no overtime work, a childcare facility in the workplace, and mental health support to reduce “feelings of irritation” and “feeling ill-qualified as a parent” could help to prevent burnout in female nurses with toddlers and infants.

Selenium and chromium are heavy metals that are highly toxic to living organisms when they are present in excess amounts. The major forms of selenium and chromium in the environment are selenate and chromate, which act as toxic analogs of sulfate in plants, inhibiting its uptake and causing sulfur deficiency. To provide simple and inexpensive means of environmental analysis for selenate and chromate, we previously developed a model system for detecting and quantifying their levels by measuring the accumulation of green fluorescent protein (GFP) in transgenic plants under the control of the sulfur-responsive promoter region of the high-affinity sulfate transporter SULTR1;2 from Arabidopsis (PSULTR1;2-GFP). However, the detection limit for both selenate and chromate was 10 μmol L−1, which was higher than the environmental standards. Here, we report a more sensitive monitoring system for selenium and chromium by combining PSULTR1;2 with another sulfur-responsive region of the sulfate transporter SULTR2;1 located in the 3ʹ-non-transcribed intergenic region (TSULTR2;1). The fusion gene construct consisting of PSULTR1;2, GFP and TSULTR2;1 (PSULTR1;2-GFP-TSULTR2;1) was introduced into Arabidopsis plants, and PSULTR1;2-GFP-TSULTR2;1 transgenic plants showed significant increases in GFP under sulfur-deficient conditions or with the addition of selenate or chromate to the growth medium. The increase in GFP depended on selenate concentration. Overall, the use of PSULTR1;2-GFPTSULTR2; 1 plants decreased the detection limits to 1 and 3 μmol L−1 for selenate and chromate, respectively, providing a highly sensitive plant-based system for detecting selenium and chromium in the environment.

Sulfur is an essential element required for plant growth. It can be found as a thiol group of proteins or non-protein molecules, and as various sulfur-containing small biomolecules, including iron-sulfur (Fe/S) clusters, molybdenum cofactor (Moco), and sulfur-modified nucleotides. Thiol-mediated redox regulation has been well investigated, whereas biosynthesis pathways of the sulfur-containing small biomolecules have not yet been clearly described. In order to understand overall sulfur transfer processes in plant cells, it is important to elucidate the relationships among various sulfur delivery pathways as well as to investigate their interactions. In this review, we summarize the information from recent studies on the biosynthesis pathways of several sulfur-containing small biomolecules and the proteins participating in these processes. In addition, we show characteristic features of gene expression in Arabidopsis at the early stage of sulfate depletion from the medium, and we provide insights into sulfur transfer processes in plant cells.

Recent studies have shown various metabolic and transcriptomic interactions between sulfur (S) and phosphorus (P) in plants. However, most studies have focused on the effects of phosphate (Pi) availability and P signaling pathways on S homeostasis, whereas the effects of S availability on P homeostasis remain largely unknown. In this study, we investigated the interactions between S and P from the perspective of S availability. We investigated the effects of S availability on Pi uptake, transport, and accumulation in Arabidopsis thaliana grown under sulfur sufficiency (+S) and deficiency (&minus, S). Total P in shoots was significantly increased under &minus, S owing to higher Pi accumulation. This accumulation was facilitated by increased Pi uptake under &minus, S. In addition, &minus, S increased root-to-shoot Pi transport, which was indicated by the increased Pi levels in xylem sap under &minus, S. The &minus, S-increased Pi level in the xylem sap was diminished in the disruption lines of PHT1, 9 and PHO1, which are involved in root-to-shoot Pi transport. Our findings indicate a new aspect of the interaction between S and P by listing the increased Pi accumulation as part of &minus, S responses and by highlighting the effects of &minus, S on Pi uptake, transport, and homeostasis.

Aim This prospective cohort study aims to clarify the factors affecting burnout in female nurses who have preschool-age children. Methods The subjects were 2151 female nurses who have preschool-age children and work at 70 city hospitals across Japan. The questionnaires were completed by 1644 female nurses with preschool-age children in October 2010, and they were divided into a cohort to observe the incidence of burnout, which was investigated in October 2011. Results At the baseline, the authors obtained responses from 1802 subjects (83.8%) who had agreed to join the study. The subjects the authors were able to investigate totaled 523, of whom 117 (22.4%) had experienced burnout. Multiple logistic regression analysis showed that influencing or predictive factors in burnout were years at the present workplace, will to continue work, assertiveness, overtime work, and spanking children. Conclusion Female nurses who have preschool-age children tend to burnout easily if they have been at their present workplace for less than 3 years, wish to quit working, respond to a child's misbehavior with spanking, are “very low” in assertiveness, or work 4–6 h of overtime per week.

Under sulfur deficiency (-S), plants induce expression of the sulfate transport systems in roots to increase uptake and root-to-shoot transport of sulfate. The low-affinity sulfate transporter SULTR2;1 is predominantly expressed in xylem parenchyma and pericycle cells in Arabidopsis thaliana roots under -S. The mechanisms underlying -S-inducible expression of SULTR2;1 in roots have remained unclear, despite the possible significance of SULTR2;1 for acclimation to low-sulfur conditions. In this investigation, examination of deletions and base substitutions in the 3'-intergenic region of SULTR2;1 revealed novel sulfur-responsive elements, SURE21A (5'-CAATGTATC-3') and SURE21B (5'-CTAGTAC-3'), located downstream of the SULTR2;1 3'-untranslated region. SURE21A and SULTR21B effectively induced reporter gene expression from fusion constructs under -S in combination with minimal promoters or promoters not inducible by -S, suggesting their versatility in controlling transcription. T-DNA insertions near SURE21A and SULTR21B abolished -S-inducible expression of SULTR2;1 in roots and reduced the uptake and root-to-shoot transport of sulfate. In addition, these mutations partially suppressed SULTR2;1 expression in shoots, without changing its -S-responsive expression. These findings indicate that SULTR2;1 contributes to the increase in uptake and internal translocation of sulfate driven by gene expression induced under the control of sulfur-responsive elements in the 3'-nontranscribed intergenic region of SULTR2;1.

Sulfur is an essential nutrient for plants and its defi ciency (−S) severely affects plant growth. To acquire limited sulfur under –S, plants have evolved signal transduction pathways resulting in enhanced sulfate uptake and assimilation. The transcript level of the high affi nity sulfate transporter SULTR1;1 is dramatically induced by –S. The –S-induced expression of SULTR1;1 is dependent on SLIM1 transcription factor which controls a broad range of –S responsive gene expression. Previously we identifi ed the sulfur-responsive element of SULTR1;1 (SURE11) which includes a 6 bp sequence, GAGACA, identical to the binding sequence of auxin response factors (ARFs). ARFs are a family of transcription factors that promote or repress the expression of auxin responsive genes. The function of ARFs is inhibited by the hetero-dimerization with Aux/IAA proteins that cannot bind to the sequence. Though SULTR1;1 expression was not modulated by exogenously applied auxin, the identity between SURE -core sequence and the ARF binding sequence suggests that one of the ARF works to induce SULTR1;1 expression under –S. In this paper, we attempt to predict which ARFs and Aux/IAA proteins potentially control –S-induced expression of SULTR1;1 by using microarray data on slim1 and the parental plants. Five ARF and seven Aux/IAA proteins were up- or down-regulated by –S in parental plants. Among them, none of the ARF modifi ed its –S response in slim1 , but fi ve Aux/IAA proteins lost their –S response in slim1 , including IAA13 and IAA28 whose positive function in sulfur assimilation had been reported. These results indicated that this method could be useful in predicting candidates for regulatory genes working in –S responsive gene expression.

Cadmium (Cd) is a highly toxic element for living organisms, hence plants have evolved a variety of detoxification mechanisms. Phytochelatins and glutathione are low-molecular-weight sulfur compounds that function as chelators and play important roles in Cd detoxification. Previous studies have shown that the transcription of the genes involved in sulfate uptake and sulfur assimilation was increased in response to Cd stress. Recently, we reported that Cd-induced sulfate uptake is mainly attributed to the function of SULTR1;2, a high affinity sulfate transporter involved in sulfate uptake from the roots. Another distinct change in sulfate distribution induced by Cd treatment was preferential accumulation of sulfate to the shoots, which is due to the induction of root-to-shoot sulfate transport through xylem. In this study, we compared previous transcriptome data taken with Cd-treated plants to get suggestions about the SULTRs involved in Cd-induced sulfate distribution to shoots. In addition to the induction of SULTR1;1 and SULTR1;2 expressions, we found that the expression of SULTR2;1, a transporter involved in root-to-shoot transport of sulfate, and SULTR4;1 and SULTR4;2, exporters of stored sulfate in vacuole, were increased in roots upon Cd treatment. These SULTRs were suggested as contributors to the increased distribution of sulfate to shoots under Cd exposure.

Selenium (Se) is an essential nutrient for many organisms but is toxic at high levels. A better understanding of plant responses to Se is important to optimize the use of plants in alleviating dietary Se deficiency or for the cleanup of Se-polluted areas. Genetic analysis among accessions of Arabidopsis thaliana showed that several genes involved in sulfur (S) assimilation may be responsible for the differences in Se resistance and accumulation, and resistance to selenite and selenate may be regulated by different genes. Molecular and biochemical studies of non-accumulator plants revealed that defense responses mediated by phytohormones (such as ethylene, jasmonic acid, and salicylic acid) play an important role in acquiring Se resistance and accumulation. Production of these phytohormones is enhanced via signal pathways of reactive oxygen species (ROS), and the signal pathways of phytohormones act in a cooperative or antagonistic manner to induce stress and S-uptake and S-metabolic genes. In this chapter, the contribution of ROS and phytohormone signaling in the acquisition of Se resistance and accumulation in Se hyper-accumulator plants was discussed, and the application of Se-responsive genes to generate transgenic plants that can detect Se in the environment was also introduced.

Sulfur is an essential element for all organisms. Plants utilize soil sulfate to synthesize an amino acid, cysteine, which is used for a variety of sulfur-containing compounds such as glutathione (GSH), methionine, proteins, lipids, coenzymes, and various secondary metabolites. Since animals cannot synthesize organic sulfur compounds from inorganic ones, sulfate assimilation in plants is important for the global sulfur cycle.

Our study showed the antibiotic susceptibility profile of toxigenic Clostridium difficile isolated from nosocomial and community-acquired CDI between 2008 and 2010. MICs of 200 C. difficile strains were determined using E®test method in the case of erythromycin, clindamycin, moxifloxacin, rifampicin, and metronidazole. All strains were susceptible to metronidazole in the study period. Resistance rates to erythromycin, clindamycin and moxifloxacin were 31%, 29.5%, and 21.5%, respectively. In the case of rifampicin, the MIC range was quite wide, 11.5% of the tested strains proved to be highly resistant (MIC ≥32 μg/ml) to rifampicin. When we compared these results with our earlier findings from 2006 to 2007, only minor changes in susceptibility over the time-periods could be observed in the case of erythromycin, clindamycin, moxifloxacin, and rifampicin, but metronidazole susceptibility did not show changes.