ZmPHR1 contributes to drought resistance by modulating phosphate homeostasis in maize.

As an essential macronutrient, phosphorus (P) is often a limiting nutrient because of its low availability and mobility in soils. Drought is a major environmental stress that reduces crop yield. How plants balance and combine P-starvation responses (PSRs) and drought resistance is unclear. In this study, we identified the transcription factor ZmPHR1 as a major regulator of PSRs that modulates phosphate (Pi) signaling and homeostasis. We found that maize zmphr1 mutants had reduced P concentration and were sensitive to Pi starvation, whereas ZmPHR1-OE lines displayed elevated Pi concentration and yields. In addition, 57% of PSR genes and nearly 70% of ZmPHR1-regulated PSR genes in leaves were transcriptionally responsive to drought. Under moderate and early drought conditions, the Pi concentration of maize decreased, and PSR genes were up-regulated before drought-responsive genes. The ZmPHR1-OE lines exhibited drought-resistant phenotypes and reduced stomatal apertures, whereas the opposite was true of the zmphr1 mutants. ZmPT7-OE lines and zmspx3 mutants, which had elevated Pi concentration, also exhibited drought resistance, but zmpt7 mutants were sensitive to drought. Our results suggest that ZmPHR1 plays a central role in integrating Pi and drought signals and that Pi homeostasis improves the ability of maize to combat drought.

The Transcription Factor NIGT1.2 Modulates Both Phosphate Uptake and Nitrate Influx during Phosphate Starvation in Arabidopsis and Maize.

Phosphorus and nitrogen are essential macronutrients for plant growth and crop production. During phosphate (Pi) starvation, plants enhanced Pi but reduced nitrate (NO3 -) uptake capacity, and the mechanism is unclear. Here, we show that a GARP-type transcription factor NITRATE-INDUCIBLE, GARP-TYPE TRANSCRIPTIOANL REPRESSOR1.2 (NIGT1.2) coordinately modulates Pi and NO3 - uptake in response to Pi starvation. Overexpression of NIGT1.2 increased Pi uptake capacity but decreased NO3 - uptake capacity in Arabidopsis (Arabidopsis thaliana). Furthermore, the nigt1.1 nigt1.2 double mutant displayed reduced Pi uptake but enhanced NO3 - uptake under low-Pi stress. During Pi starvation, NIGT1.2 directly up-regulated the transcription of the Pi transporter genes PHOSPHATE TRANSPORTER1;1 (PHT1;1) and PHOSPHATE TRANSPORTER1;4 (PHT1;4) and down-regulated expression of NO3 - transporter gene NITRATE TRANSPORTER1.1 (NRT1.1) by binding to cis-elements in their promoters. Further genetic assays demonstrated that PHT1;1, PHT1;4, and NRT1.1 were genetically epistatic to NIGT1.2 We also identified similar regulatory pathway in maize (Zea mays). These data demonstrate that the transcription factor NIGT1.2 plays a central role in modulating low-Pi-dependent uptake of Pi and NO3 -, tending toward maintenance of the phosphorus to nitrogen balance in plants during Pi starvation.

Optimized Cationic Lipid-assisted Nanoparticle for Delivering CpG Oligodeoxynucleotides to Treat Hepatitis B Virus Infection.

PURPOSE: Hepatitis B virus (HBV) infection is such a global health problem that hundreds of millions of people are HBV carriers. Current anti-viral agents can inhibit HBV replication, but can hardly eradicate HBV. Cytosine-phosphate-guanosine (CpG) oligodeoxynucleotides (ODNs) are an adjuvant that can activate plasmacytoid dendritic cells (pDCs) and conventional dendritic cells (cDCs) to induce therapeutic immunity for HBV eradication. However, efficient delivery of CpG ODNs into pDCs and cDCs remains a challenge. In this study, we constructed a series of cationic lipid-assisted nanoparticles (CLANs) using different cationic lipids to screen an optimal nanoparticle for delivering CpG ODNs into pDCs and cDCs. METHODS: We constructed different CLANCpG using six cationic lipids and analyzed the cellular uptake of different CLANCpG by pDCs and cDCs in vitro and in vivo, and further analyzed the efficiency of different CLANCpG for activating pDCs and cDCs in both wild type mice and HBV-carrier mice. RESULTS: We found that CLAN fabricated with 1,2-Dioleoyl-3-trimethylammonium propane (DOTAP) showed the highest efficiency for delivering CpG ODNs into pDCs and cDCs, resulting in strong therapeutic immunity in HBV-carrier mice. By using CLANCpG as an immune adjuvant in combination with the injection of recombinant hepatitis B surface antigen (rHBsAg), HBV was successfully eradicated and the chronic liver inflammation in HBV-carrier mice was reduced. CONCLUSION: We screened an optimized CLAN fabricated with DOTAP for efficient delivery of CpG ODNs to pDCs and cDCs, which can act as a therapeutic vaccine adjuvant for treating HBV infection.

Infrared Characterization of Isotopic Analogues of Methanediol in Aqueous Solution.

Dissolved methanediol in aqueous solution has been treated as the precursor for the formation of atmospheric formic acid in multiphase environments. In this work, methanediol, CH2(OH)2, and its isotopic analogues, CH2(OD)2, CD2(OH)2, and CD2(OD)2, in aqueous solution were prepared by dissolving paraformaldehyde and deuterium-substituted paraformaldehyde powders in H2O and D2O under reflux. Their infrared absorption contours of formaldehyde solutions at concentrations of <1 wt % are not dependent on the concentration, mainly referring to the characteristics of the monomeric configuration, and can be categorized into two parts. At wavenumbers >2000 cm-1, broad bands of moderate strengths were ascribed to the stretching modes of two OH or OD groups, observed at 3000-3700 and 2050-2750 cm-1, respectively. At wavenumbers of 950-1200 cm-1, the isotopic analogues of methanediols composed of CH2 moieties are featured with a singlet strong band at ca. 1030 cm-1, mainly attributed to the O-C-O stretching modes; the isotopic methanediols containing CD2 moieties manifested two intense bands at ca. 1100 and 980 cm-1, majorly enveloping the CD2 deformation and O-C-O stretching modes. The aforementioned spectral features were assigned on the basis of density functional theory, ωB97XD, with the basis set aug-cc-pVTZ and the solvent effect using the conductor-like polarizable continuum model. In addition, the predicted energetics suggested that the trans-methanediol is more stable than the cis- conformer by ca. 0.62 kcal mol-1 and majorly contributes to the infrared features. At higher concentrations of CH2(OH)2, extra bands at 920 and 1104 cm-1 appeared and were attributed to the C-O-C stretching modes of the dimeric/polymeric methanediol; that is, HO(CH2O)nH, n ≥ 2. These infrared characterizations of the isotopic analogues of methanediols provided suitable detection windows in the relevant atmospheric and aerosol reactions in the laboratory studies.

Correction: Arabidopsis WRKY6 Transcription Factor Acts as a Positive Regulator of Abscisic Acid Signaling during Seed Germination and Early Seedling Development.

[This corrects the article DOI: 10.1371/journal.pgen.1005833.].

The Ubiquitin E3 Ligase PRU2 Modulates Phosphate Uptake in Arabidopsis.

Phosphorus is an essential macronutrient for plants. The phosphate (Pi) concentration in soil solutions is typically low, and plants always suffer from low-Pi stress. During Pi starvation, a number of adaptive mechanisms in plants have evolved to increase Pi uptake, whereas the mechanisms are not very clear. Here, we report that an ubiquitin E3 ligase, PRU2, modulates Pi acquisition in Arabidopsis response to the low-Pi stress. The mutant pru2 showed arsenate-resistant phenotypes and reduced Pi content and Pi uptake rate. The complementation with PRU2 restored these to wild-type plants. PRU2 functioned as an ubiquitin E3 ligase, and the protein accumulation of PRU2 was elevated during Pi starvation. PRU2 interacted with a kinase CK2α1 and a ribosomal protein RPL10 and degraded CK2α1 and RPL10 under low-Pi stress. The in vitro phosphorylation assay showed that CK2α1 phosphorylated PHT1;1 at Ser-514, and prior reports demonstrated that the phosphorylation of PHT1;1 Ser-514 resulted in PHT1;1 retention in the endoplasmic reticulum. Then, the degradation of CK2α1 by PRU2 under low-Pi stress facilitated PHT1;1 to move to the plasma membrane to increase Arabidopsis Pi uptake. Taken together, this study demonstrated that the ubiquitin E3 ligase-PRU2-was an important positive regulator in modulating Pi acquisition in Arabidopsis response to low-Pi stress.

The Ubiquitin E3 Ligase PRU1 Regulates WRKY6 Degradation to Modulate Phosphate Homeostasis in Response to Low-Pi Stress in Arabidopsis.

Since phosphorus is an essential nutrient for plants, plants have evolved a number of adaptive mechanisms to respond to changes in phosphate (Pi) supply. Previously, we reported that the transcription factor WRKY6 modulates Pi homeostasis by downregulating PHOSPHATE1 (PHO1) expression and that WRKY6 is degraded during Pi starvation in Arabidopsis thaliana However, the molecular mechanism underlying low-Pi-induced WRKY6 degradation was unknown. Here, we report that a ubiquitin E3 ligase, PHOSPHATE RESPONSE UBIQUITIN E3 LIGASE1 (PRU1), modulates WRKY6 protein levels in response to low-Pi stress. A pru1 mutant was more sensitive than the wild type to Pi-deficient conditions, exhibiting a reduced Pi contents in the shoot, similar to the pho1-2 mutant and WRKY6-overexpressing line. PRU1 interacted with WRKY6 in vitro and in vivo. Under low-Pi stress, the ubiquitination and subsequent degradation of WRKY6, as well as the consequential enhancement of PHO1 expression, were impaired in pru1 PRU1 complementation lines displayed no obvious differences compared with wild-type plants. Further genetic analysis showed that disruption of WRKY6 abolished the low-Pi sensitivity of pru1, indicating that WRKY6 functioned downstream of PRU1. Taken together, this study uncovers a mechanism by which PRU1 modulates Pi homeostasis, through regulating the abundance of WRKY6 in response to low-Pi stress in Arabidopsis.

Programmable Delivery of Immune Adjuvant to Tumor-Infiltrating Dendritic Cells for Cancer Immunotherapy.

Tumor-infiltrating dendritic cells (TIDCs) are mostly immature and immunosuppressive, usually mediating immune inhibition. The utilization of cytosine-guanine oligodeoxynucleotides (CpG ODNs) to stimulate the activation of TIDCs has been demonstrated to be effective for improving antitumor immunity. However, a series of biological barriers has limited the efficacy of previous nanocarriers for delivering CpG to TIDCs. Herein, we developed a dual-sensitive dendrimer cluster-based nanoadjuvant for delivering CpG ODNs into TIDCs. We show that the tumor acidity triggers the rapid release of CpG conjugated polyamidoamine (PAMAM) dendrimers from the nanoadjuvant, thus facilitating its perfusion deep into tumors and phagocytosis by TIDCs. Thereafter, the reductive condition of the endolysosomes led to the subsequent release of CpG, which promotes the DCs activation and enhances antitumor immunotherapies. Programmable delivery of immune adjuvant efficiently overcomes the barriers for targeted delivery to TIDCs and provides a promising strategy for improving cancer immunotherapy.

Potassium and phosphorus transport and signaling in plants.

Nitrogen (N), potassium (K), and phosphorus (P) are essential macronutrients for plant growth and development, and their availability affects crop yield. Compared with N, the relatively low availability of K and P in soils limits crop production and thus threatens food security and agricultural sustainability. Improvement of plant nutrient utilization efficiency provides a potential route to overcome the effects of K and P deficiencies. Investigation of the molecular mechanisms underlying how plants sense, absorb, transport, and use K and P is an important prerequisite to improve crop nutrient utilization efficiency. In this review, we summarize current understanding of K and P transport and signaling in plants, mainly taking Arabidopsis thaliana and rice (Oryza sativa) as examples. We also discuss the mechanisms coordinating transport of N and K, as well as P and N.

Maize ZmPT7 regulates Pi uptake and redistribution which is modulated by phosphorylation.

Phosphorus, an essential mineral macronutrient, is a major constituent of fertilizers for maize (Zea mays L.) production. However, the molecular mechanisms of phosphate (Pi) acquisition in maize plants and its redistribution remain unclear. This study presents the functional characterization of ZmPT7 in Pi uptake and redistribution in maize. The ZmPT7 was expressed in roots and leaves, and induced during Pi starvation. The ZmPT7 complemented the Pi-uptake deficiency of yeast mutant phoΔnull and Arabidopsis mutant pht1;1Δ4Δ, indicating that ZmPT7 functioned as a Pi transporter. We generated zmpt7 mutants by CRISPR/Cas9 and ZmPT7-overexpressing lines. The zmpt7 mutants showed reduced, whereas the ZmPT7-overexpressing lines displayed increased Pi-uptake capacity and Pi redistribution from old to young leaves, demonstrating that ZmPT7 played central roles in Pi acquisition and Pi redistribution from old to young leaves. The ZmCK2 kinases phosphorylated ZmPT7 at Ser-521 in old maize leaves, which enhanced transport activity of ZmPT7. The Ser-520 of Arabidopsis AtPHT1;1, a conserved residue of ZmPT7 Ser-521, was also phosphorylated by AtCK2 kinase, and the mutation of Ser-520 to Glu (phosphorylation mimic) yielded enhanced transport activity of AtPHT1;1. Taken together, these results indicate that ZmPT7 plays important roles in Pi acquisition and redistribution, and its transport activity is modulated by phosphorylation.

CALCIUM-DEPENDENT PROTEIN KINASE 32-mediated phosphorylation is essential for the ammonium transport activity of AMT1;1 in Arabidopsis roots.

Protein kinase-mediated phosphorylation modulates the absorption of many nutrients in plants. CALCIUM-DEPENDENT PROTEIN KINASES (CPKs) are key players in plant signaling to translate calcium signals into diverse physiological responses. However, the regulatory role of CPKs in ammonium uptake remains largely unknown. Here, using methylammonium (MeA) toxicity screening, CPK32 was identified as a positive regulator of ammonium uptake in roots. CPK32 specifically interacted with AMMONIUM TRANSPORTER 1;1 (AMT1;1) and phosphorylated AMT1;1 at the non-conserved serine residue Ser450 in the C-terminal domain. Functional analysis in Xenopus oocytes showed that co-expression of CPK32 and AMT1;1 significantly enhanced the AMT1;1-mediated inward ammonium currents. In transgenic plants, the phosphomimic variant AMT1;1S450E, but not the non-phosphorylatable variant AMT1;1S450A, fully complemented the MeA insensitivity and restored high-affinity 15NH4+ uptake in both amt1;1 and cpk32 mutants. Moreover, in the CPK32 knockout background, AMT1;1 lost its ammonium transport activity entirely. These results indicate that CPK32 is a crucial positive regulator of ammonium uptake in roots and the ammonium transport activity of AMT1;1 is dependent on CPK32-mediated phosphorylation.

Effects of the Density of Chemical Cross-links and Physical Entanglements of Ultraviolet-Irradiated Polystyrene Chains on Domain Orientation and Spatial Order of Polystyrene-block-Poly(methyl methacrylate) Nano-Domains.

Ultraviolet irradiation (UVI) of varied duration caused cross-linking and neutralization of polystyrene (PS) homopolymers of molar mass (Mn) from 6 to 290 kg mol-1 on a silicon-oxide surface. An optimal neutral skin layer on the surface of the PS was obtained via brief UVI in air (UVIA), by which the PS had no preferential interaction with either block in the copolymer. UVI in an inert environment (gaseous dinitrogen) (UVIN) stabilized the PS layers via cross-linking and enabled the PS networks to have an effective adhesive contact with the underlying substrate. Thorough examination of domain orientations and spatial orders of a series of block copolymer, polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA), thin films deposited on these UVI-treated PS support layers yielded clear evidence that a dense layer of neutralized PS chains was required for the perpendicular orientation of PS-b-PMMA nanodomains. In particular, in addition to neutralization, two factors-the densities of physical entanglements and of chemical crosslinks-both in UVI-treated PS should be considered for the perpendicular orientation of nanolamellae and nanocylinders in symmetric and asymmetric PS-b-PMMA thin films. The density of physical entanglement in PS depends intrinsically on Mn of the PS, whereas the density of chemical cross-links was controlled with a varied duration of UVIN. Sufficiently large densities of physical entanglements and chemical cross-links can prevent PS-b-PMMA chains from penetrating through the neutral skin layer. The total density of physical entanglements and chemical cross-links required for the perpendicular orientation is correlated with the dimensions of the PS-b-PMMA chains.

Arabidopsis WRKY6 Transcription Factor Acts as a Positive Regulator of Abscisic Acid Signaling during Seed Germination and Early Seedling Development.

The phytohormone abscisic acid (ABA) plays important roles during seed germination and early seedling development. Here, we characterized the function of the Arabidopsis WRKY6 transcription factor in ABA signaling. The transcript of WRKY6 was repressed during seed germination and early seedling development, and induced by exogenous ABA. The wrky6-1 and wrky6-2 mutants were ABA insensitive, whereas WRKY6-overexpressing lines showed ABA-hypersensitive phenotypes during seed germination and early seedling development. The expression of RAV1 was suppressed in the WRKY6-overexpressing lines and elevated in the wrky6 mutants, and the expression of ABI3, ABI4, and ABI5, which was directly down-regulated by RAV1, was enhanced in the WRKY6-overexpressing lines and repressed in the wrky6 mutants. Electrophoretic mobility shift and chromatin immunoprecipitation assays showed that WRKY6 could bind to the RAV1 promoter in vitro and in vivo. Overexpression of RAV1 in WRKY6-overexpressing lines abolished their ABA-hypersensitive phenotypes, and the rav1 wrky6-2 double mutant showed an ABA-hypersensitive phenotype, similar to rav1 mutant. Together, the results demonstrated that the Arabidopsis WRKY6 transcription factor played important roles in ABA signaling by directly down-regulating RAV1 expression.

How career facilitators and barriers influence nurses' professional turnover intention.

AIMS: Our study investigates the influence of career facilitators and barriers on nurses' improvement of their professional capabilities and their professional turnover intention. BACKGROUND: Reducing nurses' professional turnover intention could help alleviate the global nursing shortage. Nevertheless, little research has addressed how career facilitators and barriers, nurses' improvement of their professional capabilities and professional turnover intention are related, indicating a gap. DESIGN: This study used a cross-sectional design. METHODS: We surveyed 502 out of 2,660 full-time nurses who worked for a medical centre in Taiwan between January-March 2018. Our items were adapted from Cunningham et al. and Teng et al. and had adequate reliability and validity. Structural equation modelling was used to test the study hypotheses. RESULTS: Human capital, social capital, and discrimination were positively related to intention to improve professional capabilities. Moreover, intention to improve professional capabilities was positively related to action to improve professional capabilities, which was negatively related to professional turnover intention. CONCLUSION: Most of the career facilitators and even barriers, boost the improvement of professional capabilities and are useful for retaining nurses in the nursing profession. IMPACT: Findings of this study should have an impact on nursing managers by offering them means to retain nurses, for example, enhancing human capital and social capital among nurses to reduce their turnover intention.

Abscisic Acid Modulates Seed Germination via ABA INSENSITIVE5-Mediated PHOSPHATE1.

The phytohormone abscisic acid (ABA) controls many developmental and physiological processes. Here, we report that PHOSPHATE1 (PHO1) participates in ABA-mediated seed germination and early seedling development. The transcription of PHO1 was obviously enhanced during seed germination and early seedling development and repressed by exogenous ABA. The pho1 mutants (pho1-2, pho1-4, and pho1-5) showed ABA-hypersensitive phenotypes, whereas the PHO1-overexpressing lines were ABA-insensitive during seed germination and early seedling development. The expression of PHO1 was repressed in the ABI5-overexpressing line and elevated in the abi5 mutant, and ABI5 can bind to the PHO1 promoter in vitro and in vivo, indicating that ABI5 directly down-regulated PHO1 expression. Disruption of PHO1 abolished the ABA-insensitive germination phenotypes of abi5 mutant, demonstrating that PHO1 was epistatic to ABI5 Together, these data demonstrate that PHO1 is involved in ABA-mediated seed germination and early seedling development and transcriptionally regulated by ABI5.

WRKY42 modulates phosphate homeostasis through regulating phosphate translocation and acquisition in Arabidopsis.

The Arabidopsis (Arabidopsis thaliana) WRKY transcription factor family has more than 70 members, and some of them have been reported to play important roles in plant response to biotic and abiotic stresses. This study shows that WRKY42 regulated phosphate homeostasis in Arabidopsis. The WRKY42-overexpressing lines, similar to the phosphate1 (pho1) mutant, were more sensitive to low-inorganic phosphate (Pi) stress and had lower shoot Pi content compared with wild-type plants. The PHO1 expression was repressed in WRKY42-overexpressing lines and enhanced in the wrky42 wrky6 double mutant. The WRKY42 protein bound to the PHO1 promoter under Pi-sufficient condition, and this binding was abrogated during Pi starvation. These data indicate that WRKY42 modulated Pi translocation by regulating PHO1 expression. Furthermore, overexpression of WRKY42 increased root Pi content and Pi uptake, whereas the wrky42 mutant had lower root Pi content and Pi uptake rate compared with wild-type plants. Under Pi-sufficient condition, WRKY42 positively regulated PHOSPHATE TRANSPORTER1;1 (PHT1;1) expression by binding to the PHT1;1 promoter, and this binding was abolished by low-Pi stress. During Pi starvation, the WRKY42 protein was degraded through the 26S proteasome pathway. Our results showed that AtWRKY42 modulated Pi homeostasis by regulating the expression of PHO1 and PHT1;1 to adapt to environmental changes in Pi availability.

Arabidopsis RAV1 transcription factor, phosphorylated by SnRK2 kinases, regulates the expression of ABI3, ABI4, and ABI5 during seed germination and early seedling development.

The phytohormone abscisic acid (ABA) modulates a number of processes during plant growth and development. In this study, the molecular mechanism of Arabidopsis RAV (Related to ABI3/VP1) transcription factor RAV1 involving ABA signaling was investigated. RAV1-underexpressing lines were more sensitive to ABA than wild-type plants during seed germination and early seedling development, whereas RAV1-overexpressing lines showed strong ABA-insensitive phenotypes. Overexpression of RAV1 repressed ABI3, ABI4, and ABI5 expression, and RAV1 bound to the ABI3, ABI4, and ABI5 promoters in vitro and in vivo, indicating that RAV1 directly down-regulates the expression of ABI3, ABI4, and ABI5. The interruption of ABI5 function in RAV1-U abi5 plants abolished the ABA-hypersensitive phenotype of RAV1-U plants, demonstrating that ABI5 is epistatic to RAV1. RAV1 interacted with SNF1-RELATED PROTEIN KINASE SnRK2.2, SnRK2.3 and SnRK2.6 in the nucleus. In vitro kinase assays showed that SnRK2.2, SnRK2.3 and SnRK2.6 phosphorylated RAV1. Transient expression assays revealed that SnRK2.2, SnRK2.3 and SnRK2.6 reduced the RAV1-dependent repression of ABI5, and the ABA-insensitive phenotype of the RAV1-overexpressing line was impaired by overexpression of SnRK2.3 in the RAV1 OE3 plants. Together, these results demonstrated that the Arabidopsis RAV1 transcription factor plays an important role in ABA signaling by modulating the expression of ABI3, ABI4, and ABI5, and that its activity is negatively affected by SnRK2s.

Arabidopsis WRKY45 transcription factor activates PHOSPHATE TRANSPORTER1;1 expression in response to phosphate starvation.

The WRKY transcription factor family has more than 70 members in the Arabidopsis (Arabidopsis thaliana) genome, and some of them are involved in plant responses to biotic and abiotic stresses. This study evaluated the role of WRKY45 in regulating phosphate (Pi) uptake in Arabidopsis. WRKY45 was localized in the nucleus and mainly expressed in roots. During Pi starvation, WRKY45 expression was markedly induced, typically in roots. WRKY45 overexpression in Arabidopsis increased Pi content and uptake, while RNA interference suppression of WRKY45 decreased Pi content and uptake. Furthermore, the WRKY45-overexpressing lines were more sensitive to arsenate, the analog of Pi, compared with wild-type seedlings. These results indicate that WRKY45 positively regulates Arabidopsis Pi uptake. Quantitative real-time polymerase chain reaction and ß-glucuronidase staining assays showed that PHOSPHATE TRANSPORTER1;1 (PHT1;1) expression was enhanced in the WRKY45-overexpressing lines and slightly repressed in the WRKY45 RNA interference line. Chromatin immunoprecipitation and electrophoretic mobility shift assay results indicated that WRKY45 can bind to two W-boxes within the PHT1;1 promoter, confirming the role of WRKY45 in directly up-regulating PHT1;1 expression. The pht1;1 mutant showed decreased Pi content and uptake, and overexpression of PHT1;1 resulted in enhanced Pi content and uptake. Furthermore, the PHT1;1-overexpressing line was much more sensitive to arsenate than WRKY45-overexpressing and wild-type seedlings, indicating that PHT1;1 overexpression can enhance Arabidopsis Pi uptake. Moreover, the enhanced Pi uptake and the increased arsenate sensitivity of the WRKY45-overexpressing line was impaired by pht1;1 (35S:WRKY45-18::pht1;1), demonstrating an epistatic genetic regulation between WRKY45 and PHT1;1. Together, our results demonstrate that WRKY45 is involved in Arabidopsis response to Pi starvation by direct up-regulation of PHT1;1 expression.

An analysis of anesthesia-controlled operating room time after propofol-based total intravenous anesthesia compared with desflurane anesthesia in ophthalmic surgery: a retrospective study.

BACKGROUND: Anesthetic techniques can contribute to reduction of anesthesia-controlled time to improve operating room (OR) efficiency. However, little is known about the difference in anesthesia-controlled time between propofol-based total IV anesthesia (TIVA) and desflurane anesthesia (DES) techniques for ophthalmic surgery under general anesthesia. METHODS: We performed a retrospective analysis using hospital databases to compare the anesthesia-controlled times of ophthalmic surgery patients receiving either TIVA via target-controlled infusion with propofol/fentanyl or desflurane/fentanyl-based anesthesia between January 2010 and December 2011. The various time intervals (surgical time, incision to surgical completion and application of dressings; anesthesia time, start of anesthesia to extubation; extubation time, surgery complete and dressings applied to extubation; time in OR, arrival in the OR to departure from the OR; postanesthetic care unit (PACU) stay time, arrival in the PACU to discharge from the PACU to the general ward; and total surgical suite time, arrival in the OR to discharge from the PACU to the general ward) that comprise a patient's hospital stay and the incidence of postoperative nausea and vomiting were compared between the 2 anesthetic techniques. RESULTS: We included data from 1405 patients, with 595 patients receiving TIVA and 810 receiving DES. The extubation time was faster (TIVA-DES = -1.85 minutes, 99.2% confidence interval [CI], -2.47 to -1.23 minutes) and the PACU stay time was shorter (TIVA-DES = -3.62 minutes, 99.2% CI, -6.97 to -0.10 minutes) in the TIVA group than in the DES group. However, there was no significant difference in total surgical suite time between groups (TIVA-DES = -5.03 minutes, 99.2% CI, -11.75 to 1.69 minutes). We performed the random-effects analyses while stratifying for procedure and showed that the extubation time in the TIVA group was faster by 14% (99.2% CI, 9% to 19%, P < 0.0001) relative to the DES group, and the PACU stay time was faster by 5% (99.2% CI, 1% to 10%, P = 0.002). Significantly fewer patients suffered postoperative nausea and vomiting and required rescue therapy in the TIVA group than in the DES group (11.3% vs 32.2%, risk difference 21.0%, 95% CI, 16.9% to 25.1%, P < 0.001 and 23.9% vs 54.0%, risk difference 30.1%, 95% CI, 18.3% to 42.0%, P = 0.002, respectively). CONCLUSIONS: In our hospital, the use of TIVA reduced the mean time to extubation by at least 9% and PACU stay time by more than 1% when compared with the use of DES anesthesia for ophthalmic surgery.

Phosphorus acquisition, translocation, and redistribution in maize.

Phosphorus (P) is an essential nutrient for crop growth, making it important for maintaining food security as the global population continues to increase. Plants acquire P primarily via the uptake of inorganic phosphate (Pi) in soil through their roots. Pi, which is usually sequestered in soils, is not easily absorbed by plants and represses plant growth. Plants have developed a series of mechanisms to cope with P deficiency. Moreover, P fertilizer applications are critical for maximizing crop yield. Maize is a major cereal crop cultivated worldwide. Increasing its P-use efficiency is important for optimizing maize production. Over the past two decades, considerable progresses have been achieved in research aimed at adapting maize varieties to changes in environmental P supply. Here, we present an overview of the morphological, physiological, and molecular mechanisms involved in P acquisition, translocation, and redistribution in maize, and combine the advances in Arabidopsis and rice, to better elucidate the progress of P nutrition. Additionally, we summarize the correlation between P and abiotic stress responses. Clarifying the mechanisms relevant to improving P absorption and use in maize can guide future research on sustainable agriculture.