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Taurine performs multiple physiological functions, and the maintenance of taurine level for most mammals relies on active uptake from diet and endogenous taurine synthesis through its synthesis enzymes, including cysteine dioxygenase (CDO). In addition, uterus tissue and uterus fluid are rich in taurine, and taurine synthesis is regulated by estrogen (EThe uterine CDO expression was assayed from the first day of plugging (d 1) to d 8 and the results showed that CDO expression level increased from d 1 to d 4, followed by a significant decline on d 5 and persisted to d 8, which was highly correlated with serum and uterine taurine levels, and serum PThe present study firstly demonstrates that taurine and CDO play prominent roles in uterine receptivity and embryo implantation by involving in E

In this study, a ZrO

Sphingosine phosphate lyase 1 (SGPL1) is a highly conserved enzyme that irreversibly degrades sphingosine-1-phosphate (S1P). Sgpl1-knockout mice fail to develop germ cells, resulting in infertility. However, the molecular mechanism remains unclear. The results of the present study showed that SGPL1 was expressed mainly in granulosa cells, Leydig cells, spermatocytes, and round spermatids. Sgpl1 deletion led to S1P accumulation in the gonads. In the ovary, S1P decreased natriuretic peptide receptor 2 (NPR2) activity in granulosa cells and inhibited early follicle growth. In the testis, S1P increased the levels of cyclin-dependent kinase inhibitor 1A (p21) and apoptosis in Leydig cells, thus resulting in spermatogenesis arrest. These results indicate that Sgpl1 deletion increases intracellular S1P levels, resulting in the arrest of female and male germ cell development via different signaling pathways.

Seed germination and seedling establishment are important for the reproductive success of plants, but seeds and seedlings typically encounter constantly changing environmental conditions. By inhibiting seed germination and post-germinative growth through the PYR1/PYL/RCAR ABA receptors and PP2C co-receptors, the phytohormone abscisic acid (ABA) prevents premature germination and seedling growth under unfavorable conditions. However, little is known about how the ABA-mediated inhibition of seed germination and seedling establishment is thwarted. Here, we report that ABA Signaling Terminator (ABT), a WD40 protein, efficiently switches off ABA signaling and is critical for seed germination and seedling establishment. ABT is induced by ABA in a PYR1/PYL/RCAR-PP2C-dependent manner. Overexpression of ABT promotes seed germination and seedling greening in the presence of ABA, whereas knockout of ABT has the opposite effect. We found that ABT interacts with the PYR1/PYL/RCAR and PP2C proteins, interferes with the interaction between PYR1/PYL4 and ABI1/ABI2, and hampers the inhibition of ABI1/ABI2 by ABA-bound PYR1/PYL4, thereby terminating ABA signaling. Taken together, our results reveal a core mechanism of ABA signaling termination that is critical for seed germination and seedling establishment in Arabidopsis.

The selective N-monomethylation of primary anilines was realized by the use of the Me3N-BH3/N,N-dimethylformamide (DMF) system as the methyl source. This method also allows for the controllable introduction of N-CH2D, N-CHD2, and N-CD3 units with high levels of deuterium incorporation using Me3N-BH3/d7-DMF, Me3N-BD3/DMF and Me3N-BD3/d7-DMF systems, respectively.

Abscisic acid (ABA) is a key regulator of plant responses to abiotic stresses, such as drought. Abscisic acid receptors and coreceptors perceive ABA to activate Snf1-related protein kinase2s (SnRK2s) that phosphorylate downstream effectors, thereby activating ABA signaling and the stress response. As stress responses come with fitness penalties for plants, it is crucial to tightly control SnRK2 kinase activity to restrict ABA signaling. However, how SnRK2 kinases are inactivated remains elusive. Here, we show that NUCLEAR PORE ANCHOR (NUA), a nuclear pore complex (NPC) component, negatively regulates ABA-mediated inhibition of seed germination and post-germination growth, and drought tolerance in Arabidopsis thaliana. The role of NUA in response to ABA depends on SnRK2.2 and SnRK2.3 for seed germination and on SnRK2.6 for drought. NUA does not directly inhibit the phosphorylation of these SnRK2s or affects their abundance. However, the NUA-interacting protein EARLY IN SHORT DAYS 4 (ESD4), a SUMO protease, negatively regulates ABA signaling by directly interacting with and inhibiting SnRK2 phosphorylation and protein levels. More importantly, we demonstrated that SnRK2.6 can be SUMOylated in vitro, and ESD4 inhibits its SUMOylation. Taken together, we identified NUA and ESD4 as SnRK2 kinase inhibitors that block SnRK2 activity, and reveal a mechanism whereby NUA and ESD4 negatively regulate plant responses to ABA and drought stress possibly through SUMOylation-dependent regulation of SnRK2s.

Porcine spermatozoa are stored in the oviductal isthmus after natural mating, and the number of spermatozoa is increased in the oviductal ampulla when the mature cumulus-oocyte complexes (COCs) are transferred into the ampulla. However, the mechanism is unclear. Herein, natriuretic peptide type C (NPPC) was mainly expressed in porcine ampullary epithelial cells, whereas its cognate receptor natriuretic peptide receptor 2 (NPR2) was located on the neck and the midpiece of porcine spermatozoa. NPPC increased sperm motility and intracellular Ca2+ levels, and induced sperm release from oviduct isthmic cell aggregates. These actions of NPPC were blocked by the cyclic guanosine monophosphate (cGMP)-sensitive cyclic nucleotide-gated (CNG) channel inhibitor l-cis-Diltiazem. Moreover, porcine COCs acquired the ability to promote NPPC expression in the ampullary epithelial cells when the immature COCs were induced to maturation by epidermal growth factor (EGF). Simultaneously, transforming growth factor-β ligand 1 (TGFB1) levels were dramatically increased in the cumulus cells of the mature COCs. The addition of TGFB1 promoted NPPC expression in the ampullary epithelial cells, and the mature COC-induced NPPC was blocked by the transforming growth factor-β type 1 receptor (TGFBR1) inhibitor SD208. Taken together, the mature COCs promote NPPC expression in the ampullae via TGF-β signaling, and NPPC is required for the release of porcine spermatozoa from the oviduct isthmic cells.

This paper reports the non-targeted analysis of unknown volatile components in scented stationery based on headspace gas chromatography-Orbitrap high-resolution mass spectrometry. The volatiles released from the samples (22 scented erasers and 17 scented pens) under specific headspace conditions were analyzed. A qualitative analysis of unknown substances was carried out according to four identification steps (step 1: comprehensive score and retention index, step 2: identification of molecular ion peaks by chemical ionization, step 3: fragment ion detail comparison for distinguishing isomers, step 4: verification by chemical standards). A total of 101 volatile substances were identified in the scented erasers, and 86 volatile substances were identified in the scented pens. The identified substances were divided into eight categories. Aliphatic hydrocarbons, aromatic hydrocarbons, esters, and alcohols were the top four groups of substances identified in scented erasers and pens. The identified substances were further filtered and screened according to their detection rate, toxicity, and response intensity. Finally, 14 high-risk volatile chemicals in scented stationery were listed. This study can be used as a reference for identifying unknown substances and as a guide for monitoring volatile chemicals in products and assessing their possible risks to consumers.

This paper reports the non-targeted analysis of unknown volatile chemicals in medical masks through headspace gas chromatography-Orbitrap high-resolution mass spectrometry. In view of the difficulties that may be encountered in the qualitative analysis of unknown substances, several typical cases and the corresponding reliable solutions are given from the perspective of comprehensive score and retention index, chemical ionization identification molecular formula, fragment ion detail comparison for distinguishing isomers, and identification of alkanes. With this method, 69 volatile substances were identified in 60 masks. The identified substances were divided into nine categories. Alkanes, esters, benzenes, and alcohols were the top four groups of substances identified in masks and accounted for 34.8%, 15.9%, 10.1%, and 7.2% of the total substances, respectively. In addition, ketones, ethers, phenolics, amides, and other substances were identified. Ethanol, 1,4-dichlorobenzene, toluene, m-xylene, dimethyl glutarate, and N,N-dimethylacetamide had high detection rates. The identified substances were further filtered and screened according to their detection rate, toxicity, and response intensity. Finally, 12 high-risk volatile chemicals in medical masks were listed. This study could serve as a reference for identifying unknown substances and a guide for monitoring volatile chemicals in masks and promoting chemical safety improvements in products.

Numerous studies have shown that patients with COVID-19 have a high incidence of renal dysfunction. However, the dialysis supplies, including dialysates, are also severely inadequate in hospitals at the pandemic centers. Therefore, there is an urgent need to develop materials that can efficiently and rapidly remove toxins and thus regenerate dialysate to make this vital resource remains readily available. In this work, by simple carbonization and activation treatment, the porous activated carbon from waste rubber seed shell (RAC) was prepared. The adsorption results showed that the maximum adsorption capacities of the obtained RAC for creatinine and uric acid were 430 mg/g and 504 mg/g, respectively. Significantly, the adsorption process can be close to the equilibrium state within 0.5 h, which proved the ultra-fast adsorption response capacity of RAC. Further, the thermodynamics analysis results showed that both the creatinine and uric acid adsorption processes were monolayer, exothermic, and spontaneous. The adsorption kinetics results indicated that the adsorption process of the two uremic toxins followed the pseudo-second-order rate model and was dominated by chemisorption. The instrument analysis results reflected the efficient adsorption of the RAC for the above uremic toxins which might be due to the dipole–dipole interaction between the dipolar oxygen-containing groups of the surface of RAC and the dipoles of the toxins. Moreover, the formed hydrogen bonds between the oxygen groups and the toxins also played an important role. In all, the as-prepared RAC has the potential to efficiently remove major toxins from the dialysate and can be used in in vitro dialysis of numerous patients during the current COVID-19 pandemic.

The adsorption of chlorinated aromatic compounds (CACs) on pristine biochar was often limited. Surface modification can greatly improve the adsorption capacity of biochar. In this work, by pyrolysis activation of rubber-seed shell wastes, nitrogen auto-doped biochar (RSS-NBC) was synthesized and used for purifying CACs-containing wastewater. Systematic characterization results showed that after proper treatment, the as-prepared RSS-NBC had high specific surface area (SSABET=2328 m2/g), abundant surface oxygen- and nitrogen-containing functional groups (e. g. hydroxyl, carboxyl and pyrrole nitrogen, etc.), and nano-scale pore structure (∼3nm). Batch adsorption experiments were conducted with using three typical CACs probing pollutants, i.e., 1,2-dichlorobenzene (1,2-DCB), 2,4-dichlorophenol (2,4-DCP) and 2,4-dichlorobenzoic acid (2,4-DCBA). The adsorption experiments results showed that the maximum adsorption amounts of 1, 2-DCB, 2,4-DCP, and 2,4-DCBA could reach 2284, 1921, and 1142 mg/g at 298.15 K. Moreover, 90% of the equilibrium adsorption amount can be reached within 0.5 h. The adsorption kinetic results showed that the adsorption processes of the three CACs followed the pseudo-second-order rate model and were dominated by chemisorption. Also, the adsorption isotherms of 1, 2-DCB and 2, 4-DCP belonged to the Freundlich model and were valid for multilayer adsorption, while the adsorption of 2,4-DCBA followed Langmuir model and single-layer adsorption. The thermodynamics data indicated that the spontaneous adsorption process of 1, 2-DCB and 2, 4-DCP was endothermic while that of 2,4-DCBA was exothermic. After 5 cycles of adsorption-regeneration, the removal efficiency of RSS-NBC particles still remained more than 80% for the three typical CACs, indicating that it could be reused as an effective and retrievable adsorbent in the treatment of CACs-containing effluents.

A bicomponent colorimetric probe based on carbon quantum dots (CQDs) and o-phenylenediamine (OPD) was established for the detection of Cu

MIL-100(Fe), a kind of iron-based metal-organic framework materials (MOFs), can be synthesized at room temperature or hydrothermal conditions, which are promising precursor materials for preparing photocatalysts to degrade some recalcitrant chlorophenols in industrial wastewater. However, the relationship between the structural characterization of MIL-100(Fe) derivatives and their photodegradation behavior of chlorophenol pollutants is still unclear. Thus, in this work, a porous Z-scheme α-Fe2O3/MIL-100(Fe) composite was successfully fabricated via partial-pyrolysis of MIL-100(Fe) precursor synthesized through green synthesis route, which was further used for degrading high-concentration of 2,4-dichlorophenol under visible-light illumination (λ > 420 nm). The effects of synthesis route and pyrolysis temperature of MIL-100(Fe) on the degradation efficiencies of as-derived materials for 2,4-dichlorophenol were investigated. The structure-activity relationship was illuminated in detail. Otherwise, the influence of several process factors, i.e., initial concentration and pH of the 2,4-dichlorophenol solution, catalyst dosage on the degradation efficiency of 2,4-dichlorophenol has also been performed. The removal efficiency of 2,4-dichlorophenol with the initial concentration of 100 mg L−1 reached up to 87.65% under optimized conditions. Lastly, the possible mechanism was explored based on trapping experiments and some other characterization results. The study in this paper not only exhibited new insight into the modified α-Fe2O3 material with high photocatalytic activity but also provided a promising method for treating wastewater containing 2,4-dichlorophenol or other similar organic pollutants.

Traditionally. slippery lubricant infused surfaces, inspired by Nepenthes, suffer from low durability, owing to the migrating, evaporating, and leaking of the infused lubricants. Herein, to address...

Combining polymeric materials and conductive one-dimensional metal nanostructures is able to achieve enhanced chemical and electrical properties, but the control over their morphology and spatial arrangement remains a big challenge. Herein, by replacing benzenedicarboxylate (BDC) in ZnBDC nanoplates with oleylamine (OAM) in the presence of HAuCl4, Zn-OAM nanobelts with a highly ordered laminar structure were obtained, on which ultrathin Au nanowires (Au NWs) were deposited and aligned along the long axes of the nanobelts. The resulting Zn-OAM/Au NW hybrid further underwent an OAM-to-2-methylimidazole ligand exchange, resulting in the formation of porous nanobelts composed of ZIF-8 nanocrystals interwound with aligned Au NWs. Due to the synergistic effect between the polymeric and metallic structures, the Zn-OAM/Au NW hybrid nanobelts and ZIF-8/Au NW porous nanobelts demonstrated fast and selective gas sensing at ambient conditions, in sharp contrast to the nonresponsive Au NWs or Zn-based polymers alone.

Corticotropin-releasing-factor (CRF) is a key regulator of catecholamines (CATs) biosynthesis in the adrenal gland. Furthermore, miR-375 has been confirmed to be localized in the mouse adrenal gland. However, the relationships between miR-375 and CRF in regulating CATs biosynthesis remain to be established. This study was designed to investigate the relationship between CRF and miR-375 in the regulation of CATs biosynthesis in the porcine adrenal gland. Eight adult female pigs (four controls; four injected intracerebroventricularly with 50 μg of CRF) were used for the in vivo experiments in this study. The results showed that miR-375 was exclusively localized in porcine adrenal medullary cells. Functional studies showed that miR-375 negatively regulated CATs synthesis in primary cells by affecting the expression of the CATs synthetases tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), and phenylethanolamine-N-methyltransferase (PNMT). CRF up-regulated the expression of CATs synthetase in primary adrenal medullary cells under basal conditions and upon endogenous miR-375 inhibition; the enhanced effects vanished when cellular miR-375 was overexpressed by transfecting miR-375-mic. CRF decreased the expression of miR-375 both in vivo and in vitro. Our in vitro results showed that CRF significantly decreased the expression of miR-375, perhaps by binding to CRFR1. miR-375 functions by directly binding to the 3'-UTR region of specificity protein 1 (Sp1), which is involved in regulating Th and Dbh expression. These data collectively indicate that miR-375 plays an important role in regulating CATs synthesis and mediates the CRF signaling pathway in porcine adrenal medullary cells.

A direct Csp3–H methylenation of 2-arylacetamides using DMF/Me2NH-BH3 as the methylene source was developed. The formyl group of DMF delivered the carbon and one hydrogen atoms, and the Me2NH-BH3 donated the remaining one hydrogen atom. This protocol offers a new alternative to make useful 2-arylacrylamides from simple starting materials.

In eukaryotes, homotypic fusion and vacuolar protein sorting (HOPS) as well as class C core vacuole/endosome tethering (CORVET) are evolutionarily conserved membrane tethering complexes that play important roles in lysosomal/vacuolar trafficking. Whether HOPS and CORVET control endomembrane trafficking in pollen tubes, the fastest growing plant cells, remains largely elusive. In this study, we demonstrate that the four core components shared by the two complexes, Vacuole protein sorting 11 (VPS11), VPS16, VPS33, and VPS18, are all essential for pollen tube growth in Arabidopsis thaliana and thus for plant reproduction success. We used VPS18 as a representative core component of the complexes to show that the protein is localized to both multivesicular bodies (MVBs) and the tonoplast in a growing pollen tube. Mutant vps18 pollen tubes grew more slowly in vivo, resulting in a significant reduction in male transmission efficiency. Additional studies revealed that membrane fusion from MVBs to vacuoles is severely compromised in vps18 pollen tubes, corroborating the function of VPS18 in late endocytic trafficking. Furthermore, vps18 pollen tubes produce excessive exocytic vesicles at the apical zone and excessive amounts of pectin and pectin methylesterases in the cell wall. In conclusion, this study establishes an additional conserved role of HOPS/CORVET in homotypic membrane fusion during vacuole biogenesis in pollen tubes and reveals a feedback regulation of HOPS/CORVET in the secretion of cell wall modification enzymes of rapidly growing plant cells.

In this work, we developed a microfluidic paper-based analytical device (μPAD) for the on-line isolation of proteins and the electrochemical detection of lead ions (Pb(II)) in urine samples. The patterned filter paper was prepared through the direct printing of microchannel patterns on filter paper using an office laser printer. The paper was modified with protein precipitant and was then coupled with a detachable three-electrode system. Experimental parameters, namely, modification reagents, microchannel length and width, deposition potential, and deposition time, were optimized. Then, the maximum protein concentration under which the device can function was obtained as 300 mg L−1. The linear range was 10–500 μg L−1 with a detection limit of 9 μg L−1. The effectiveness of this device was demonstrated through the quantification of Pb(II) in urine samples and the results agreed with those of atomic absorption spectrometry (AAS).

BackgroundAbscisic acid (ABA) plays an important role in plant growth and adaptation through the ABA signaling pathway. The ABA-responsive element binding (AREB/ABF) family transcriptional factors are central regulators that integrate ABA signaling with various signaling pathways. It has long been known that ABA inhibits rhizobial infection and nodule formation in legumes, but the underlying molecular mechanisms remain elusive.ResultsHere, we show that nodulation is very sensitive to ABA and exogenous ABA dramatically inhibits rhizobial infection and nodule formation in soybean. In addition, we proved that GmbZIP1, an AREB/ABF transcription factor, is a major regulator in both nodulation and plant response to ABA in soybean.GmbZIP1was specifically expressed during nodule formation and development. Overexpression ofGmbZIP1resulted in reduced rhizobial infection and decreased nodule number. Furthermore,GmbZIP1is responsive to ABA, and ectopic overexpression ofGmbZIP1increased sensitivity of Arabidopsis plants to ABA during seed germination and postgerminative growth, and conferred enhanced drought tolerance of plants. Remarkably, we found that GmbZIP1 directly binds to the promoter ofGmENOD40–1, a marker gene for nodule formation, to repress its expression.ConclusionOur results identified GmbZIP1 as a node regulator that integrates ABA signaling with nodulation signaling to negatively regulate nodule formation.

The selective N-monomethylation of primary anilines was realized by the use of the Me3N-BH3/N,N-dimethylformamide (DMF) system as the methyl source. This method also allows for the controllable introduction of N-CH2D, N-CHD2, and N-CD3 units with high levels of deuterium incorporation using Me3N-BH3/d7-DMF, Me3N-BD3/DMF and Me3N-BD3/d7-DMF systems, respectively.

In flowering plants, each pollen tube delivers two sperm cells into the ovule to complete double fertilization. During the process, pollen tubes need to be navigated into the ovule, where accurate and complex pre-ovule guidance and ovule guidance are required. In recent years, different methods have been established to study those genes involved in the regulation of pollen tube guidance. Semi-in vivo ovule targeting mimics in vivo pollen tube micropylar guidance, and the semi-in vivo ovule targeting assay has been used to investigate function of genes involved in micropylar guidance. Moreover, the ovule targeting assay is the best way to do live cell imaging, which facilitates observation of pollen tube reception, synergid cell degeneration, and semi-in vivo gamete fusion. Meanwhile, semi-in vivo pollen tube attraction assay is another useful method to directly determine whether a certain molecule has pollen tube attraction activity.

Mutant phenotype observation is the most useful and important method to study which biological process a gene-of-interest is involved in. In flowering plants, excessive pollen grains land and germinate on the stigma, then pollen tubes grow through the transmitting tract to reach the ovules, eventually enter the micropyle to complete double fertilization. First, for mutants whose homozygotes could not be obtained due to pollen tube defects, it is difficult to observe the defect phenotype since the pollen grains of different genotypes are mixed together. Here, we provide a detailed protocol to pick out mutant pollen grains from the heterozygous mutant plants in Arabidopsis thaliana. By using this method, we could obtain sufficient mutant pollen grains for phenotypic analysis. Second, it is difficult to compare the pollen/pollen tube behavior of two different genotypes/species in vivo in a same pistil. Here, we develop a new dual staining method which combines GUS staining with aniline blue staining. By using this method, we can analyze the competence of the two different pollen tubes in the same pistil.

A total of 90 wooden toys were collected, and six wood preservatives (chlorophenols and lindane) were analyzed by using gas chromatography–tandem mass spectrometry to assess the exposure risk of children to wood preservatives through oral contact with wooden toys. The detection rates of six preservatives ranged from 2.2% to 22.2%. The contents of the preservatives ranged from 0.6 µg/kg to 9.6 µg/kg. 2,4-Dichlorophenol (2,4-DCP) and 2,4,6-trichlorophenol (2,4,6-TCP) had higher detection rates and contents than other preservatives. Thus, their migration behaviors from toys to saliva were further investigated. In 11 positive samples, the max migration ratios of 2,4-DCP and 2,4,6-TCP ranged from 7.1% to 20.3% and from 11.1% to 24.8%, respectively. For children aged 3–36 months, the daily average 2,4-DCP exposure level associated with wooden toys ranged from 2.7 pg/(kg day) to 46.9 pg/(kg day), and the daily average 2,4,6-TCP exposure ranged from 3.6 pg/(kg day) to 69.4 pg/(kg day). The contribution to exposure provided by the saliva mobilization pathway was more than that provided by the ingestion of scraped-off toys, and the exposure level of 2,4,6-TCP was greater than that of 2,4-DCP. The max hazard quotient for 2,4-DCP was 1.9 × 10−4, and the max cancer risk for 2,4,6-TCP was 1.2 × 10−9. The above results indicated that although wood preservatives were distributed in wooden toys, exposure arising from directly mouthing these materials currently does not pose unacceptable risks to children.

In flowering plants, each pollen tube delivers two sperm cells into the ovule to complete double fertilization. During the process, pollen tubes need to be navigated into the ovule, where accurate and complex pre-ovule guidance and ovule guidance are required. In recent years, different methods have been established to study those genes involved in the regulation of pollen tube guidance. Semi-in vivo ovule targeting mimics in vivo pollen tube micropylar guidance, and the semi-in vivo ovule targeting assay has been used to investigate function of genes involved in micropylar guidance. Moreover, the ovule targeting assay is the best way to do live cell imaging, which facilitates observation of pollen tube reception, synergid cell degeneration, and semi-in vivo gamete fusion. Meanwhile, semi-in vivo pollen tube attraction assay is another useful method to directly determine whether a certain molecule has pollen tube attraction activity.

DELLA (GAI/RGA/RGL1/RGL2/RGL3) proteins are key negative regulators in GA (gibberellin) signaling and are involved in regulating plant growth as a response to environmental stresses. It has been shown that the DELLA protein PROCERA (PRO) in tomato promotes drought tolerance, but its molecular mechanism remains unknown. Here, we showed that the gai-1 (gibberellin insensitive 1) mutant (generated from the gai-1 (Ler) allele (with a 17 amino acid deletion within the DELLA domain of GAI) by backcrossing gai-1 (Ler) with Col-0 three times), the gain-of-function mutant of GAI (GA INSENSITIVE) in Arabidopsis, increases drought tolerance. The stomatal density of the gai-1 mutant was increased but its stomatal aperture was decreased under abscisic acid (ABA) treatment conditions, suggesting that the drought tolerance of the gai-1 mutant is a complex trait. We further tested the interactions between DELLA proteins and ABF2 (abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors) and found that there was a strong interaction between DELLA proteins and ABF2. Our results provide new insight into DELLA proteins and their role in drought stress tolerance.

Legumes have evolved photosynthesis and symbiotic nitrogen fixation for the acquisition of energy and nitrogen nutrients. During the transition from heterotrophic to autotrophic growth, blue light primarily triggers photosynthesis and low soil nitrogen induces symbiotic nodulation. Whether and how darkness and blue light influence root symbiotic nodulation during this transition is unknown. Here, we show that short-term darkness promotes nodulation and that blue light inhibits nodulation through two soybean TGACG-motif-binding factors (STF1 and STF2), which are Papilionoideae-specific transcription factors and divergent orthologs of Arabidopsis ELONGATED HYPOCOTYL 5 (HY5). STF1 and STF2 negatively regulate soybean nodulation by repressing the transcription of nodule inception a (GmNINa), which is a central regulator of nodulation, in response to darkness and blue light. STF1 and STF2 are not capable of moving from the shoots to roots, and they act both locally and systemically to mediate darkness- and blue-light-regulated nodulation. We further show that cryptochromes GmCRY1s are required for nodulation in the dark and partially contribute to the blue light inhibition of nodulation. In addition, root GmCRY1s mediate blue-light-induced transcription of STF1 and STF2, and intriguingly, GmCRY1b can interact with STF1 and STF2 to stabilize the protein stability of STF1 and STF2. Our results establish that the blue light receptor GmCRY1s-STF1/2 module plays a pivotal role in integrating darkness/blue light and nodulation signals. Furthermore, our findings reveal a molecular basis by which photosensory pathways modulate nodulation and autotrophic growth through an intricate interplay facilitating seedling establishment in response to low nitrogen and light signals.

A hydrophobic carboxyl functionalized phosphonium-based ionic liquid (IL) ((5-carboxypentyl) triphenylphosphonium bis (trifluoromethyl)sulfonyl) amide, TPP-HA[TFSI]) was synthesized through a simple hydrothermal approach. Based on the π-π and cation-π interactions with multi-wall carbon nanotubes (MWCNTs), a TPP-HA[TFSI]@MWCNTs hybrid was prepared to immobilize hemoglobin (Hb) to fabricate a simple and effective electrochemical sensing platform for the detection of methyl parathion (MP) in vegetables. Spectroscopic and electrochemical results show that TPP-HA[TFSI]@MWCNTs substrate synergistically provided a good biocompatible microenvironment for Hb, and the hydrophobicity of TPP-HA[TFSI] and the π-π interaction and hydrogen bonding between TPP-HA[TFSI]@MWCNTs, Hb and nafion (NF) were conducive to maintain the stability and integrity of the modified electrode interface. The TPP-HA[TFSI]@MWCNTs with large surface area and high conductivity promoted the exposure of the electroactive center of Hb and the direct electron transfer between Hb and the electrode, which effectively amplified the electrochemical signal and improved the sensitivity of MP detection. The constructed electrochemical sensing platform had a wider linear range (2–14 ng mL-1) and a lower detection limit (0.62 ng mL-1) for MP, and had acceptable repeatability, reproducibility, stability and anti-interference ability. This results indicated that the phosphonium-based ILs functionalized MWCNTs was an effective substrate for the immobilization of biological components, which have broad prospect in the construction of electrochemical sensing interfaces.

Leaves are essential organs for plants. We previously identified a functional gene possibly encoding a component of the SWI/SNF complex named Leaf and Flower Related (LFR) in Arabidopsis thaliana. Loss-of-function mutants of LFR displayed obvious defects in leaf morphogenesis, indicating its vital role in leaf development. Here an allelic null mutant of ASYMMETRIC LEAVES2 (AS2), as2-6, was isolated as an enhancer of lfr-1 in petiole length, vasculature pattern and leaf margin development. The lfr as2 double-mutants showed enhanced ectopic expression of BREVIPEDICELLUS (BP) compared with each of the single-mutants, which is consistent with their synergistic genetic enhancement in multiple BP-dependent development processes. Moreover, LFR and several putative subunits of the SWI/SNF complex interacted physically with AS2. LFR associated with BP chromatin in an AS1-AS2-dependent manner to promote the nucleosome occupancy for appropriate BP repression in leaves. Taken together, our findings reveal that LFR and the SWI/SNF complex play roles in leaf development at least partly by repressing BP transcription as interacting factors of AS2, which expounds our understanding of BP repression at the chromatin structure level in leaf development.

The ultra-low k dielectrics have been widely used as semiconductor technology steps into 45 nm, 28 nm, and more advanced nodes. Combined with the rapid shrinks of critical dimensions, the ultra-low k dielectrics face challenges to retain the benefits of interconnect scaling both on their manufacturability and reliability performances. In this paper, abnormal failure phenomena were investigated on 28 nm ILD (Intra Level Dielectric) and IMD (Inter Metal Dielectric) qualifications and 40 nm mass production. A new failure mechanism of metal 1 to poly (M1-to-poly) leaky path was proposed based on theoretical investigations and experiments. Based on our newly proposed dielectric breakdown mechanism, a series of innovative test structures were designed for early detections and evaluations of reliability performances. These newly designed test structures have been proven to be useful due to better representing actual using profiles, more precise reliability evaluations, and more effective monitors on process variations at mass production.

Object: This paper presents a method for the determination of migration of six phthalate esters in plastic toys based on gas chromatography-tandem mass spectrometry (GC-MS/MS) coupled with solid phase extraction using cucurbiturils (CB6-8) as adsorbent. Method: On the base of self-made migration device, toy samples were migrated for 10 min to 24 h in simulated saliva at 37 °C. The analytes were adsorbed by cucurbiturils SPE cartridges, eluted with ethyl acetate, then determined by GC-MS/MS and quantified by external standard method. The eluting solvents as well as the type and amount of the extraction materials were carefully optimized, then the reusability of the SPE cartridges was investigated. The limits of quantification (LOQs) ranged from 2.5 µg/L to 12.5 µg/L. Average recoveries of target analytes (spiked at three concentration levels) were in the range of 82.7% to 94.4%. Intraday repeatability and interday repeatability of the method varied from 2.3% to 6.6% and from 5.6% to 10.8%, respectively. Conclusion: The proposed method was finally used to explore the migration behavior of phthalate esters in commercial plastic toys.

As somatic cells in the testis seminiferous tubule, Sertoli cells provide the medium for spermatogenesis. One of the important functions of Sertoli cells is synthesizing and secreting cell factors to affect the production of sperm; however, much of those molecular regulation mechanisms remain unknown. Here, we confirm the localization of protein SPATA2 (spermatogenesis-associated protein 2), which had previously been shown to be highly expressed in Sertoli cells of the adult mouse testis. To further conduct a functional study, we generated SPATA2 global knockout mice via use of the CRISPR/Cas9n gene editing technology. The 120-day-old knockout mice testes showed almost a 40% decrease in size and weight and variations in the histomorphology of the seminiferous epithelium, with a 40% decrease in sperm count. Further examination revealed that the proliferation of germ cells in the seminiferous tubules was attenuated by 28%. In addition, we found that SPATA2 deletion led to an approximately 70% increase in the inhibin alpha-subunit mRNA and protein level in the testes compared to that of wild-type mice. Our data revealed the impact of SPATA2 on male fertility and suggested that SPATA2 ensures the normal secretory function of Sertoli cells.

Significant efforts have been made in revealing the mechanism of thaumasite formation in concrete, which continues to be fraught with ambiguities and dissension. Chemical method was employed to synthesize pure C3S, C2S, C3A, ettringite, and thaumasite, and X-ray diffraction (XRD), Raman spectroscopy and infrared spectroscopy (IR) were used to identify thaumasite from other hydrates. To investigate the direct route of thaumasite formation, C3S, C2S, gypsum, and calcium carbonate were used to prepare a cement paste so that the interference of ettringite formation can be avoided. The indirect route of thaumasite formation was also studied by considering the effect of C3A or ettringite content on thaumasite formation. Results show that thaumasite can be definitely generated in the absence of aluminium-bearing minerals or ettringite under appropriate conditions, while the ettringite presence promotes the thaumasite formation. No evidences support the heterogeneous nucleation route in this work. It is concluded that the method mentioned in this work can surely be used to investigate the mechanism of thaumasite formation, and thaumasite can form by both direct and woodfordite routes.

We report a sensitive electrochemical protocol based on an easy-to-produce and disposable plastic electrode for the determination of total chromium (Cr) and Cr(VI). The electrode was fabricated by sputtering a thin layer of gold on a polyethylene terephthalate (PET) substrate. The experimental factors influencing the fabrication and electrochemical analysis as well as potential interferences were investigated. Under optimum conditions, the determination of total Cr was achieved by adsorptive cathodic stripping voltammetry and the linear range was from 5 to 70 μg L − 1 and from 70 to 300 μg L − 1 with a limit of detection of 5 μg L − 1 . The analysis of Cr(VI) was performed by amperometry and linearity in the range from 0.5 to 100 μg L − 1 with a limit of detection of 0.5 μg L − 1 was obtained. The applicability to spiked river water and textile samples was demonstrated with satisfying results. The proposed method has been proved to provide more convenient sensor fabrication and much higher sensitivity than other reports based on disposable electrodes. We believe it may provide a promising alternative for routine analysis of total Cr and Cr(VI).

DELLA (GAI/RGA/RGL1/RGL2/RGL3) proteins are key negative regulators in GA (gibberellin) signaling and are involved in regulating plant growth as a response to environmental stresses. It has been shown that the DELLA protein PROCERA (PRO) in tomato promotes drought tolerance, but its molecular mechanism remains unknown. Here, we showed that the gai-1 (gibberellin insensitive 1) mutant (generated from the gai-1 (Ler) allele (with a 17 amino acid deletion within the DELLA domain of GAI) by backcrossing gai-1 (Ler) with Col-0 three times), the gain-of-function mutant of GAI (GA INSENSITIVE) in Arabidopsis, increases drought tolerance. The stomatal density of the gai-1 mutant was increased but its stomatal aperture was decreased under abscisic acid (ABA) treatment conditions, suggesting that the drought tolerance of the gai-1 mutant is a complex trait. We further tested the interactions between DELLA proteins and ABF2 (abscisic acid (ABA)-responsive element (ABRE)-binding transcription factors) and found that there was a strong interaction between DELLA proteins and ABF2. Our results provide new insight into DELLA proteins and their role in drought stress tolerance.

Adaptive changes in plant phenology are often considered to be a feature of the so-called ‘domestication syndrome’ that distinguishes modern crops from their wild progenitors, but little detailed evidence supports this idea. In soybean, a major legume crop, flowering time variation is well characterized within domesticated germplasm and is critical for modern production, but its importance during domestication is unclear. Here, we identify sequential contributions of two homeologous pseudo-response-regulator genes, Tof12 and Tof11, to ancient flowering time adaptation, and demonstrate that they act via LHY homologs to promote expression of the legume-specific E1 gene and delay flowering under long photoperiods. We show that Tof12-dependent acceleration of maturity accompanied a reduction in dormancy and seed dispersal during soybean domestication, possibly predisposing the incipient crop to latitudinal expansion. Better understanding of this early phase of crop evolution will help to identify functional variation lost during domestication and exploit its potential for future crop improvement.

A MoS2-nanosheet-decorated C-N/Co4S3 (C-N/Co4S3@MoS2) nanorod with multi-defects was synthesized by using a core-shell zeolitic imidazole framework (ZIF-8@ZIF-67) as the precursor. The C-N/Co4S3@MoS2 hybrid showed high activity towards the hydrogen evolution reaction and the oxygen evolution reaction. This work provides a new strategy to find MoS2-based bifunctional electrocatalysts through MOF precursors. Keywords: MoS2 nanosheet, Hydrogen evolution reaction, Oxygen evolution reaction, Bifunctional electrocatalyst

An aptasensor is described for the electrochemical determination of bisphenol A (BPA). Gold-coated multiwalled carbon nanotubes (Au/MWCNTs) and a single-stranded DNA-dye complex are used as a double signal-amplification system. The BPA-binding aptamer was assembled on a disposable electrode modified with Au/MWCNTs. Methylene blue (MB) was then intercalated into the immobilized aptamer with an approximately molecular ratio of 4 to form a complex. Upon interaction with BPA, the immobilized aptamer underwent a conformational change. This causes the intercalated MB to be released from the complex into solution. As a result, the electrochemical signal of the intercalated MB, typically measured using square wave voltammetry at a potential of -0.20 V (vs. Ag/AgCl (saturated KCl)) decreases. The fabrication of the aptasensor was characterized by the scanning electron microscopy, atomic force microscopy, and electrochemical techniques. Under optimal experimental conditions, the current drops linearly with the logarithm of BPA concentrations over the range from 10 fM to 1 nM, and the limit of detection is 8 fM. The assay was applied to the determination of BPA in plastic drinking bottles, tap water, and milk. Graphical AbstractSchematic illustration of fabricating the aptasensor for bisphenol A (BPA) based on double signal amplification via gold-coated multiwalled carbon nanotubes (Au/MWCNT) and an aptamer-dye complex. PET: poly(ethylene terephthalate).

A direct Csp3-H methylenation of 2-arylacetamides using DMF/Me2NH-BH3 as the methylene source was developed. The formyl group of DMF delivered the carbon and one hydrogen atoms, and the Me2NH-BH3 donated the remaining one hydrogen atom. This protocol offers a new alternative to make useful 2-arylacrylamides from simple starting materials.

Racing to fertilization Pollen tubes, which carry plant sperm, need to grow from where they land in the flower to where the ovule is. Zhong et al. now show how pollen from related plant species race to reach the ovule first. One set of fast-evolving peptide signals is tuned to speed up growth of conspecific pollen tubes. A related set of evolutionarily ancient peptides is tuned to attract all pollen tubes. Thus, fertilization is more likely to happen through conspecific pollen tubes, but a fail-safe system encourages even the laggards to get where they need to go. Science , this issue p. eaau9564

Herein, we report a multi–residue method based on dissolution–precipitation extraction combined with gas chromatography-tandem mass spectrometry (GC–MS/MS) analysis for targeted screening and quantification of 216 harmful chemicals in plastic children’s toys. We established a spectrogram database containing the first-order mass spectra of all analytes and their second-order mass spectra at different collision energies. Good separation was attained in less than 60 min. As a simple and low–cost extraction method, dissolution–precipitation exhibited good recoveries for the analytes in the plastic samples. The matrix–matched standard curves were accurate for analyte quantification in specific plastics due to the solvent effects and matrix effects. The limits of quantification range were 0.1 mg/kg to 10 mg/kg. A wide linear range of 0.1–200 mg/kg was also observed, with r2≥0.9924. The average recoveries ranged from 63.9% to 137.6%, and the relative standard deviation (n = 6) varied from 0.6% to 13.2%. Finally, 31 ABS actual toys and 30 PVC actual toys were detected and 20 analytes with contents ranging from 0.4 mg/kg to 172 mg/kg and 30 analytes from 0.8 mg/kg to 141,030 mg/kg were discovered respectively.