Genome-wide identification, structural characterization and gene expression analysis of the WRKY transcription factor family in pea (Pisum sativum L.)

BACKGROUND

The WRKY gene family is one of the largest families of transcription factors in higher plants, and WRKY transcription factors play important roles in plant growth and development as well as in response to abiotic stresses; however, the WRKY gene family in pea has not been systematically reported.

RESULTS

In this study, 89 pea WRKY genes were identified and named according to the random distribution of PsWRKY genes on seven chromosomes. The gene family was found to have nine pairs of tandem duplicates and 19 pairs of segment duplicates. Phylogenetic analyses of the PsWRKY and 60 Arabidopsis WRKY proteins were performed to determine their homology, and the PsWRKYs were classified into seven subfamilies. Analysis of the physicochemical properties, motif composition, and gene structure of pea WRKYs revealed significant differences in the physicochemical properties within the PsWRKY family; however, their gene structure and protein-conserved motifs were highly conserved among the subfamilies. To further investigate the evolutionary relationships of the PsWRKY family, we constructed comparative syntenic maps of pea with representative monocotyledonous and dicotyledonous plants and found that it was most recently homologous to the dicotyledonous WRKY gene families. Cis-acting element analysis of PsWRKY genes revealed that this gene family can respond to hormones, such as abscisic acid (ABA), indole-3-acetic acid (IAA), gibberellin (GA), methyl jasmonate (MeJA), and salicylic acid (SA). Further analysis of the expression of 14 PsWRKY genes from different subfamilies in different tissues and fruit developmental stages, as well as under five different hormone treatments, revealed differences in their expression patterns in the different tissues and fruit developmental stages, as well as under hormone treatments, suggesting that PsWRKY genes may have different physiological functions and respond to hormones.

CONCLUSIONS

In this study, we systematically identified WRKY genes in pea for the first time and further investigated their physicochemical properties, evolution, and expression patterns, providing a theoretical basis for future studies on the functional characterization of pea WRKY genes during plant growth and development.

Genome-wide identification, evolution, and role of SPL gene family in beet (Beta vulgaris L.) under cold stress

BACKGROUND

SPL transcription factors play vital roles in regulating plant growth, development, and abiotic stress responses. Sugar beet (Beta vulgaris L.), one of the world's main sugar-producing crops, is a major source of edible and industrial sugars for humans. Although the SPL gene family has been extensively identified in other species, no reports on the SPL gene family in sugar beet are available.

RESULTS

Eight BvSPL genes were identified at the whole-genome level and were renamed based on their positions on the chromosome. The gene structure, SBP domain sequences, and phylogenetic relationship with Arabidopsis were analyzed for the sugar beet SPL gene family. The eight BvSPL genes were divided into six groups (II, IV, V, VI, VII, and VIII). Of the BvSPL genes, no tandem duplication events were found, but one pair of segmental duplications was present. Multiple cis-regulatory elements related to growth and development were identified in the 2000-bp region upstream of the BvSPL gene start codon (ATG). Using quantitative real-time polymerase chain reaction (qRT-PCR), the expression profiles of the eight BvSPL genes were examined under eight types of abiotic stress and during the maturation stage. BvSPL transcription factors played a vital role in abiotic stress, with BvSPL3 and BvSPL6 being particularly noteworthy.

CONCLUSION

Eight sugar beet SPL genes were identified at the whole-genome level. Phylogenetic trees, gene structures, gene duplication events, and expression profiles were investigated. The qRT-PCR analysis indicated that BvSPLs play a substantial role in the growth and development of sugar beet, potentially participating in the regulation of root expansion and sugar accumulation.

Full-field exposure of larval zebrafish to narrow waveband LED light sources at defined power and energy for optogenetic applications

BACKGROUND

Optogenetic approaches in transparent zebrafish models have provided numerous insights into vertebrate neurobiology. The purpose of this study was to develop methods to activate light-sensitive transgene products simultaneously throughout an entire larval zebrafish.

NEW METHOD

We developed a LED illumination stand and microcontroller unit to expose zebrafish larvae reproducibly to full field illumination at defined wavelength, power, and energy.

RESULTS

The LED stand generated a sufficiently flat illumination field to expose multiple larval zebrafish to high power light stimuli uniformly, while avoiding sample bath warming. The controller unit allowed precise automated delivery of predetermined amounts of light energy at calibrated power. We demonstrated the utility of the approach by driving photoconversion of Kaede (398 nm), photodimerization of GAVPO (450 nm), and photoactivation of dL5**/MG2I (661 nm) in neurons throughout the CNS of larval zebrafish. Observed outcomes were influenced by both total light energy and its rate of delivery, highlighting the importance of controlling these variables to obtain reproducible results.

COMPARISON WITH EXISTING METHODS

Our approach employs inexpensive LED chip arrays to deliver narrow-waveband light with a sufficiently flat illumination field to span multiple larval zebrafish simultaneously. Calibration of light power and energy are built into the workflow.

CONCLUSIONS

The LED illuminator and controller can be constructed from widely available materials using the drawings, instructions, and software provided. This approach will be useful for multiple optogenetic applications in zebrafish and other models.

Chromosome-level genome assembly and population genomic analysis provide novel insights into the immunity and evolution of Sogatella furcifera

Sogatella furcifera is a destructive agricultural pest causing large threats to rice production in China and Southeast Asian countries. Despite recent breakthroughs in long-read sequencing, high quality genomic data are very limited in S. furcifera. In present study, a chromosome-level assembly of the S. furcifera genome was completed (0.64 GB), comprising 15 chromosomes covered 95.04% of the estimated genome size, along with other 624 small scaffolds making up the remaining 4.96% of the genome of S. furcifera. A total of 24,669 protein-coding genes, 1211 long noncoding RNA and 7595 circular RNA transcripts were predicted in this study. Comparative genomic analysis revealed rapidly evolved genes were associated with multiple immune-related pathways in S. furcifera. Genome resequencing of 44 individuals from 12 geographic populations revealed frequent gene flow among populations. The systemic genomic analysis will provide more insights into the understanding of the immunity and evolutionary adaptation of S. furcifera.

All-Polymer Solar Cells Sequentially Solution Processed from Hydrocarbon Solvent with a Thick Active Layer

Organic solar cells (OSCs) have gained increasing attention. Among the various directions in OSCs, all-polymer solar cells (all-PSCs) have emerged as a highly promising and currently active research area due to their excellent film formation properties, mechanical properties, and thermal stabilities. However, most of the high-efficiency all-PSCs are processed from chloroform with an active layer thickness of ~100 nm. In order to meet the requirements for industrialization, a thicker active layer processed from low-vapor pressure solvents (preferentially a hydrocarbon solvent) is strongly desired. Herein, we employ toluene (a hydrocarbon solvent with a much higher boiling point than chloroform) and a method known as sequential processing (SqP) to mitigate the rapid decline in efficiency with increasing film thickness. We show that SqP enables a more favorable vertical phase segregation that leads to less trap-assisted recombination and enhanced charge extraction and lifetime than blend-cast devices at higher film thicknesses.

Adrenocortical pheochromocytoma diagnosed during pregnancy: a case report

This paper reports a rare case of adrenocortical carcinoma (ACC) diagnosed during pregnancy presenting with gestational hypertension. Hypertensive disorders in pregnancy should receive enough attention to identify and exclude the possibility of adrenal diseases, thereby making a timely diagnosis and active treatment.

CLDN6 Suppresses Migration and Invasion of MCF-7 and SKBR-3 Breast Cancer Cells by Blocking the SMAD/Snail/MMP-2/9 Axis

The study examined the mechanisms of action of signal protein claudin 6 (CLDN6) on migration and invasion of breast cancer cell lines MCF-7 and SKBR-3. To this end, the signal proteins SMAD were blocked with their inhibitor SB431542, the genes CLDN6 and SNAIL were knocked down with short hairpin RNAs, and MMP2 and MMP9 were inhibited with TIMP-1. Expressions of MMP2 and MMP9 mRNAs were evaluated by reverse transcription PCR, Expressions of MMP-2, MMP-9, E-cadherin, N-cadherin, and vimentin were examined by Western blotting. Migration and invasion were analyzed by scratch test and Matrigel invasion assay. SB431542 inhibited expression of MMP2 and MMP9 in both cell lines. Single use of SB431542 inhibited expression of MMP-2/MMP-9 and corresponding mRNAs, but subsequent silencing of CLDN6 gene reversed this effect. TIMP-1 reversed down-regulation of E-cadherin, upregulation of N-cadherin and vimentin, facilitation of migration and invasion evoked by CLDN6 knocking down. Silencing of SNAIL gene inhibited migration and invasion, upregulated the expression of E-cadherin, and down-regulated expression of MMP2, MMP 9, N-cadherin, and vimentin. Thus, CLDN6 suppresses the epithelial-mesenchymal transition, migration, and invasion via blocking SMAD/Snail/MMP-2/9 signaling pathway in MCF-7 and SKBR-3 cancer cell lines.

Ultrasound-Guided Urokinase in the Remedy of Spontaneous Vaginal Hematoma After Vaginal Delivery: A Case Report

Introduction

Vaginal hematoma is commonly treated by traditional incision and sutures. In this report, we describe the treatment of a spontaneous vaginal hematoma after vaginal delivery by ultrasound-guided urokinase injection.

Case Presentation

A 32-year-old multipara developed a spontaneous vaginal hematoma after vaginal delivery. The hematoma diagnosed via ultrasound examination of the postpartum pelvic basin was located in the posterior vaginal wall, and measured to be 8.92 × 5.71 cm from transvaginal ultrasonography. After considering the size and position of the hematoma, treatment by urokinase injection under ultrasound guidance was selected and performed three times. Forty-two days after the last treatment, the hematoma had disappeared.

Discussion and Conclusion

For patients in stable condition, when incision and sutures of vaginal hematoma after natural delivery is difficult to perform, urokinase injection under ultrasound guidance can be an effective treatment method that helps in the absorption of the hematoma.

MicroRNA-708 suppresses the proliferation, migration, and invasion of human retinoblastoma cells by targeting RAP2B, a member of the RAS oncogene family

Retinoblastoma generally affects children and causes permanent vision failure or even death. MicroRNAs (miRs) have recently gained much attention during recent years. The miR-708 acts as a tumor suppressor in several human cancers, but the former has not been functionally characterized in human retinoblastoma. The present study was designed to investigate the role of miR-708 in human retinoblastoma. The results showed that miR-708 is significantly (P<0.05) downregulated in retinoblastoma cell lines. MiR-708 overexpression significantly (P<0.05) inhibited retinoblastoma cell growth and proliferation by inducing apoptosis. Furthermore, retinoblastoma cells overexpressing miR-708 exhibited a markedly lower migratory rate and invasiveness compared to negative control cells. The bioinformatics and dual luciferase assay revealed a RAS oncogene family protein, RAP2B, which acts as the regulatory target and functional mediator of the molecular role of miR-708 in retinoblastoma. Together, the present study revealed the tumor suppressor role of miR-708 and pointed to the therapeutic implications of miR-708/RAP2B in the treatment of retinoblastoma.

Changes of Barley Stripe Rust Populations in the United States from 1993 to 2017

Barley stripe rust is a relatively new disease in the United States. The pathogen, Puccinia striiformis f. sp. hordei (Psh), was first observed in Texas in 1991 and has spread north and westwards and mainly caused epidemics in the western United States. A total of 447 isolates collected from 1993 to 2017 were identified as 382 multilocus genotypes (MLGs) using 14 simple sequence repeat markers. The MLGs were clustered into six molecular groups (MGs) using the discriminant analysis of principal components and the hierarchical cluster analysis, and the MGs had significant differences in frequency in different years. MG1 was present in the population prior to the year 2000. MG2, MG3, and MG4 became predominate after 2000. MG5 was detected in all 24 years but more frequent from 2010 to 2017. MG6 was the most recent group detected mainly from 2011 to 2017 and had the highest correlation coefficient with the virulence phenotypes among the MGs. The heterozygosity and genotypic diversity of the Psh populations increased from 2000 to 2017, even more from 2010 to 2017. The results indicate rapid genetic changes from year to year, with major molecular group changes around 2000 and 2010. The possible mechanisms underlying the population changes are discussed.

Quantification of functional recovery in a larval zebrafish model of spinal cord injury

Human spinal cord injury (SCI) is characterized by permanent loss of damaged axons, resulting in chronic disability. In contrast, zebrafish can regenerate axonal projections following central nervous system injury and re-establish synaptic contacts with distant targets; elucidation of the underlying molecular events is an important goal with translational potential for improving outcomes in SCI patients. We generated transgenic zebrafish with GFP-labeled axons and transected their spinal cords at 10 days post-fertilization. Intravital confocal microscopy revealed robust axonal regeneration following the procedure, with abundant axons bridging the transection site by 48 h post-injury. In order to analyze neurological function in this model, we developed and validated new open-source software to measure zebrafish lateral trunk curvature during propulsive and turning movements at high temporal resolution. Immediately following spinal cord transection, axial movements were dramatically decreased caudal to the lesion site, but preserved rostral to the injury, suggesting the induction of motor paralysis below the transection level. Over the subsequent 96 h, the magnitude of movements caudal to the lesion recovered to baseline, but the rate of change of truncal curvature did not fully recover, suggesting incomplete restoration of caudal strength over this time course. Quantification of both morphological and functional recovery following SCI will be important for the analysis of axonal regeneration and downstream events necessary for restoration of motor function. An extensive array of genetic and pharmacological interventions can be deployed in the larval zebrafish model to investigate the underlying molecular mechanisms.

FtbZIP12 Positively Regulates Responses to Osmotic Stress in Tartary Buckwheat

ABFs play a key role in regulating plant osmotic stress. However, in Tartary buckwheat, data on the role of ABF genes in osmotic stress remain limited and its associated mechanism in osmoregulation remain nebulous. Herein, a novel ABF family in Tartary buckwheat, FtbZIP12, was cloned and characterized. FtbZIP12 is a transcriptional activator located in the nucleus; its expression is induced by NaCl, mannitol, and abscisic acid (ABA). Atopic expression of FtbZIP12 in Arabidopsis promoted seed germination, reduced damage to primary roots, and improved the tolerance of seedlings to osmotic stress. The quantitative realtime polymerase chain reaction (RT-qPCR) results showed that the expressions of the typical genes related to stress, the SOS pathway, and the proline synthesis pathway in Arabidopsis were significantly (p < 0.05) upregulated under osmotic stress. FtbZIP12 improved the osmotic pressure resistance by reducing the damage caused by reactive oxygen species to plants and maintained plant homeostasis by upregulating the expression of genes related to stress, osmotic regulation, and ion homeostasis. This study identified a key candidate gene for understanding the mechanism underlying osmotic-stress-regulated function in Tartary buckwheat, thereby providing a theoretical basis for improving its yield and quality.

The plasma membrane-localized OsNIP1;2 mediates internal aluminum detoxification in rice

Aluminum (Al) toxicity significantly restricts crop production on acidic soils. Although rice is highly resistant to Al stress, the underlying resistant mechanisms are not fully understood. Here, we characterized the function of OsNIP1;2, a plasma membrane-localized nodulin 26-like intrinsic protein (NIP) in rice. Aluminum stress specifically and quickly induced OsNIP1;2 expression in the root. Functional mutations of OsNIP1;2 in two independent rice lines led to significantly enhanced sensitivity to Al but not other metals. Moreover, the Osnip1;2 mutants had considerably more Al accumulated in the root cell wall but less in the cytosol than the wild-type rice. In addition, compared with the wild-type rice plants, the Osnip1;2 mutants contained more Al in the root but less in the shoot. When expressed in yeast, OsNIP1;2 led to enhanced Al accumulation in the cells and enhanced sensitivity to Al stress, suggesting that OsNIP1;2 facilitated Al uptake in yeast. These results suggest that OsNIP1;2 confers internal Al detoxification via taking out the root cell wall's Al, sequestering it to the root cell's vacuole, and re-distributing it to the above-ground tissues.

[Factors analysis of worsening renal function in patients with acute right ventricular myocardial infarction during hospitalization]

Objective: To analyze the related factors of worsening renal function (WRF) in patients with acute right ventricular myocardial infarction (RVMI) during hospitalization. Methods: A total of 98 patients with acute RVMI admitted to the emergency comprehensive ward of Beijing Anzhen Hospital from August 2011 to January 2020 were enrolled in this cross-sectional study. According to the situation of WRF, the patients were divided into non-WRF group (76 cases) and WRF group (22 cases). WRF was defined as ≥0.3 mg/dL increase in serum creatinine level from baseline on day 6 of hospitalization (if hospital stay<6 days, it was at discharge). Baseline data, intravenous fluid infusion, diuretic and significant positive balance of patients' intake and output volume [any 24 h intakes and outputs ≥1 000 ml or any consecutive 72 h intakes and outputs ≥2 000 ml within 6 d of hospitalization (if hospitalization<6 d, it was from admission to discharge)] were obtained, and the differences of above indicators between the two groups were analyzed. Multiple logistic regression model was used to analyze the related factors of WRF. Results: The ages of patients in WRF group and non-WRF group were 60 (50, 68) and 63 (52, 72) years, and the male proportions were 63.6% (14 cases) and 76.3% (58 cases), respectively, and there was no significant difference (all P>0.05). The proportion of positive balance was 31.8% (7 cases) in WRF group, which was higher than 14.5% (11 cases) in non-WRF group (P=0.034). The rate of loop diuretic use in WRF group was 4.5% (1 case), lower than that in non-WRF group 10.5% (8 cases) (P=0.027). After adjusting for age, sex, baseline estimated glomerular filtration rate (eGFR), preoperative isoproterenol/temporary pacemaker/atropine use, significant positive balance of intake and output volume, and loop diuretic use, it was found that eGFR≥60 ml·min^-1·1.73 m^-2 and significant positive balance were associated with WRF, the OR (95%CI) were 0.71 (0.62-0.86) and 1.21 (1.02-1.43) (both P<0.05); After eliminating the variable of significant positive balance in the above model, loop diuretic use was found to be a correlation factor for WRF, with an OR (95%CI) of 0.89 (0.72-0.97) (P<0.05). Conclusions: Significant positive balance of intake and output volume during hospitalization in patients with acute RVMI is a risk factor for WRF on day 6 or at discharge. In the presence of a significant positive balance, loop diuretic use is a protective factor for WRF.

Identification of Secreted Protein Gene-Based SNP Markers Associated with Virulence Phenotypes of Puccinia striiformis f. sp. tritici, the Wheat Stripe Rust Pathogen

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is a destructive disease that occurs throughout the major wheat-growing regions of the world. This pathogen is highly variable due to the capacity of virulent races to undergo rapid changes in order to circumvent resistance in wheat cultivars and genotypes and to adapt to different environments. Intensive efforts have been made to study the genetics of wheat resistance to this disease; however, no known avirulence genes have been molecularly identified in Pst so far. To identify molecular markers for avirulence genes, a Pst panel of 157 selected isolates representing 126 races with diverse virulence spectra was genotyped using 209 secreted protein gene-based single nucleotide polymorphism (SP-SNP) markers via association analysis. Nineteen SP-SNP markers were identified for significant associations with 12 avirulence genes: AvYr1, AvYr6, AvYr7, AvYr9, AvYr10, AvYr24, AvYr27, AvYr32, AvYr43, AvYr44, AvYrSP, and AvYr76. Some SP-SNPs were associated with two or more avirulence genes. These results further confirmed that association analysis in combination with SP-SNP markers is a powerful tool for identifying markers for avirulence genes. This study provides genomic resources for further studies on the cloning of avirulence genes, understanding the mechanisms of host–pathogen interactions, and developing functional markers for tagging specific virulence genes and race groups.

Random coding method for SNR enhancement of BOTDR

A random coding method for a Brillouin optical time domain reflectometer (BOTDR) fiber sensor is proposed. In this method, a series of pulses modulated by random code are injected into the optical fiber to enhance the signal-to-noise ratio (SNR) and further improve the measurement accuracy. Random coding method allows the sensing range to be extended to several tens of kilometers while maintaining meter-scale spatial resolution and lower detection peak power, without modifying the conventional configuration of BOTDR. The decoding principle and the coding gain of random coding method are analyzed and simulated. We experimentally implement the method and evaluate its influence on the performance optimization of BOTDR. Compared with the single pulse with peak power of 10 mW, the measured BFS uncertainty over 4.93 km sensing fiber is reduced from 5.34 MHz to 0.38 MHz when 512-bit random coding pulses with the same peak power are utilized. The experimental results show that the coding gain of 11.93 dB is obtained by 512-bit random coding. Benefitting from the SNR enhancement, the sensing range is extended from 4.93 km to 64.76 km within a root-mean-square error (RMSE) of 3 MHz, when the pulse peak power is only 10 mW and the spatial resolution is 2 m.

Constructing Environmental-Friendly "Oil-Diode" Janus Membrane for Oil/Water Separation

Oil leakage is a global environmental issue and happens frequently, resulting in a waste of oil resources and even threatening the safety of marine creatures and humans. Because of unidirectional oil transportation performance, "oil-diode" Janus membranes have attracted lots of attention for oil/water separation. However, the hydrophobic side of traditional "oil-diode" Janus membrane is completely hydrophobic, resulting in an easy permeation of oil, which hampers light oil recycling. Herein, we provide a facile approach to develop "oil-diode" Janus membranes with the special wettable structure for fast oil refining. The material characteristics and surface wettability of the membranes that generate superimposed efforts are vital to fabricate "oil-diode" Janus membranes. Interestingly, the manufactured membranes exhibit extra-high oil intrusion pressure up to 12 kPa and present high permeance of about 2993 L m^-2 h^-1 bar^-1 in separating stable water-in-oil emulsion containing surfactant and separation efficiency up to 99.6%, thereby showing promising potential in oil recovery and refining.

Transcriptome Analysis of the Molecular Patterns of Pear Plants Infected by Two Colletotrichum fructicola Pathogenic Strains Causing Contrasting Sets of Leaf Symptoms

Colletotrichum fructicola infects pear leaves, resulting in two major symptoms: tiny black spots (TS) followed by severe early defoliation and big necrotic lesions (BnL) without apparent damage depending on the pathotypes. How the same fungal species causes different symptoms remains unclear. To understand the molecular mechanism underlying the resulting diseases and the diverse symptoms, two C. fructicola pathogenetic strains (PAFQ31 and PAFQ32 responsible for TS and BnL symptoms, respectively) were inoculated on Pyrus pyrifolia leaves and subjected to transcriptome sequencing at the quiescent stage (QS) and necrotrophic stage (NS), respectively. In planta, the genes involved in the salicylic acid (SA) signaling pathway were upregulated at the NS caused by the infection of each strain. In contrast, the ethylene (ET), abscisic acid (ABA), and jasmonic acid (JA) signaling pathways were specifically related to the TS symptoms caused by the infection of strain PAFQ31, corresponding to the yellowish and early defoliation symptoms triggered by the strain infection. Correspondingly, SA was accumulated in similar levels in the leaves infected by each strain at NS, but JA was significantly higher in the PAFQ31-infected as measured using high-performance liquid chromatography. Weighted gene co-expression network analysis also reveals specific genes, pathways, phytohormones, and transcription factors (TFs) associated with the PAFQ31-associated early defoliation. Taken together, these data suggest that specific metabolic pathways were regulated in P. pyrifolia in response to the infection of two C. fructicola pathotypes resulting in the diverse symptoms: JA, ET, and ABA accumulated in the PAFQ31-infected leaves, which negatively affected the chlorophyll metabolism and photosynthesis pathways while positively affecting the expression of senescence-associated TFs and genes, resulted in leaf yellowing and defoliation; whereas SA inhibited JA-induced gene expression in the PAFQ32-infected leaves, which led to hypersensitive response-like reaction and BnL symptoms.

E2F transcription factor 1 (E2F1) enhances the proliferation, invasion and EMT of trophoblast cells by binding to Zinc Finger E-Box Binding Homeobox 1 (ZEB1)

Preeclampsia (PE) is a serious pregnancy syndrome, which is mainly caused by attenuated trophoblast proliferation and invasion. It has been verified that E2F transcription factor 1 (E2F1) is lowly expressed in PE. It is identified that E2F1 binds to the promoter region of Zinc Finger E-Box Binding Homeobox 1 (ZEB1) in JASPAR datasets. ZEB1 is also a transforming factor that can facilitate EMT. The present work was designed to investigate the biological functions of E2F1 and ZEB1 on the proliferation, invasiveness and EMT of trophoblast cells and further explore the molecular mechanism underlying the participation of E2F1 and ZEB1 in the behaviors of trophoblast cells. Results revealed that upregulation of E2F1 reinforced the proliferation, invasiveness and EMT of trophoblast cells and downregulation of E2F1 exhibited opposite effects on trophoblast proliferation, invasion and EMT. It was confirmed that E2F1 bound to the promoter region of ZEB1 and two binding sites (E1 and E2) in ZEB1 promoter region to E2F1 was identified by CHIP assays. Luciferase reporter assay further verified the binding relationship between E2F1 and ZEB1. Overexpression of ZEB1 rescued the suppressing effects of E2F1 knockdown on proliferation, invasiveness and EMT of trophoblast cells. To conclude, E2F1 could promote trophoblast proliferation and invasion and strengthen EMT of trophoblast cells by enhancing ZEB1 expression.

The roles of selectivity filters in determining aluminum transport by AtNIP1;2

Aquaporins (AQPs) are channel proteins involved in transporting a variety of substrates. It has been proposed that the constriction regions in the central pores of the AQP channels play a crucial role in determining transport substrates and activities of AQPs. Our previous results suggest that AtNIP1;2, a member of the AQP superfamily in Arabidopsis, facilitates aluminum transport across the plasma membrane. However, the functions of the constriction regions in AtNIP1;2-mediated transport activities are unclear. This study reports that residue substitutions of the constriction regions affect AtNIP1;2-mediated aluminum uptake, demonstrating the critical roles of the constriction regions for transport activities. Furthermore, a constriction region that partially or wholly mimics AtNIP5;1, a demonstrated boric-acid transporter, could not render the boric-acid transport activity to AtNIP1;2. Therefore, besides the constriction regions, other structural features are also involved in determining the nature of AtNIP1;2's transport activities.Abbreviations: AIAR: alanine-isoleucine-alanine-arginine; AIGR: alanine-isoleucine-glycine- arginine; AQP: aquaporin; Al-Mal: aluminum-malate; ar/R: aromatic/arginine; AVAR: alanine-valine-alanine-arginine; CK: control; H: helical domain; ICP-MS: inductively coupled plasma mass spectrometry; LA - LE: inter-helical loops A to E; NIP: nodulin 26-like intrinsic protein; NPA: asparagine-proline-alanine; NPG: asparagine-proline- glycine; NPS: asparagine-proline-Serine; NPV: asparagine-proline-valine; ORF: open reading frame; PIP: plasma membrane intrinsic proteins; SIP: small basic intrinsic proteins; TM: transmembrane helices; WIAR: tryptophan-isoleucine-alanine-arginine; WVAR: tryptophan-valine-alanine-arginine; WVGR: tryptophan-valine-glycine- arginine.

A new strain of Volutella citrinella with nematode predation and nematicidal activity, isolated from the cysts of potato cyst nematodes in China

BACKGROUND

Plant parasitic nematodes (PPNs) are responsible for causing many plant diseases and are extremely difficult to control at present. Currently, due to the negative effects of chemical agents on the environment and human health, the development of new biological pesticides has become an important part of plant nematode control. Nematophagous fungi refers to a class of fungi that kill plant nematodes. Notably, a large number of nematophagous fungi resources remain to be studied. The objective of our study was to use in vitro screening to identify nematophagous fungi and select strains that were highly active against nematodes, providing a primary research for the development and utilization of new nematophagous fungi.

RESULTS

A new nematophagous fungal strain (GUCC2219) was isolated from cysts of possibly Globodera spp. and Heterodera spp., identified as Volutella citrinella. The hyphae of V. citrinella produced ring structures of variable size and exhibited predatory and nematicidal activity. The hyphal predation rates (in vitro) against three species of nematodes, Aphelenchoides besseyi, Bursaphelenchus xylophilus, and Ditylenchus destructor, averaged 59.45, 33.35, and 50.95%, respectively, while the fermentation broth produced by the fungus exhibited mortality rates of 100, 100, and 55.63%, respectively, after 72 h.

CONCLUSION

V. citrinella is a new strain with nematophagous properties, which are a novel discovery. At the same time, this is the first report of nematicidal and nematode predation activity in the genus Volutella.

Polarization-fading suppression of Φ-OTDR with Rayleigh gray-scale pattern aggregation method

Polarization diversity reception is a widely used method to suppress polarization fading of Φ-optical time domain reflectometer (Φ-OTDR). However, the traditional polarization diversity reception method with multichannel point-to-point signal aggregation causes the discontinuity of the aggregated signal, which affects the subsequent application. In order to decrease the discontinuity of the aggregation signal, an area-to-area signal aggregation method with a Rayleigh gray-scale pattern is proposed. First, the Rayleigh pattern is simulated to verify the large-scale continuity of fading areas. Then, an image-processing method by Rayleigh gray-scale pattern is carried out for the automatic judgment of large-scale fading areas, which includes the operations of normalization, graying, comparison of amplitude threshold using the Otsu algorithm, erosion, and dilation. The experimental results indicate that multichannel area-to-area signal aggregation can reduce the average fading ratio from 6.58% to 2.10% and also realize the signal demodulation with an SNR of 15.83 dB of positioning curve. This aggregation method provides an effective scheme for the polarization-fading suppression for Φ-OTDR.

Genotyping Puccinia striiformis f. sp. tritici Isolates with SSR and SP-SNP Markers Reveals Dynamics of the Wheat Stripe Rust Pathogen in the United States from 1968 to 2009 and Identifies Avirulence-Associated Markers

Stripe rust, caused by Puccinia striiformis f. sp. tritici, is a devastating disease of wheat (Triticum aestivum) in the United States. The fungal pathogen can rapidly evolve, producing new virulent races infecting previously resistant cultivars and genotypes adapting to different environments. The objective of this study was to investigate the long-term population dynamics of P. striiformis f. sp. tritici in the United States. Through genotyping 1,083 isolates taken from 1968 to 2009, using 14 simple sequence repeat (SSR) markers and 92 secreted protein single nucleotide polymorphism (SP-SNP) markers, 614 and 945 genotypes were detected, respectively. In general, the two types of markers produced consistent genetic relationships among the P. striiformis f. sp. tritici populations over the 40-year period. The prior-to-2000 and the 2000-to-2009 populations were significantly different, with the latter showing higher genotypic diversity and higher heterozygosity than the earlier populations. Clustering analyses using genotypes of either SSR or SP-SNP markers revealed three molecular groups (MGs), MG1, MG2, and MG3. The prior-to-2000 and the 2000-to-2009 groups both had evidence of MG1 and MG2; however, MG3 was only found in the 2000-to-2009 population. Some of the isolates in the period of 2000 to 2009 formed individual clusters, suggesting exotic incursions. Other isolates of the same period were clustered with prior-to-2000 isolates, indicating that they were developed from the previously established populations. The data suggest the coexistence of newly introduced populations alongside established populations in the United States. Twenty SP-SNP markers were significantly associated to individual avirulence genes. These results are useful for developing more accurate monitoring systems and provide guidance for disease management.

Molecular Characterization of Wheat Stripe Rust Pathogen (Puccinia striiformis f. sp. tritici) Collections from Nine Countries

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most important diseases of wheat worldwide. To understand the worldwide distribution of its molecular groups, as well as the diversity, differentiation, and migration of the Pst populations, 567 isolates collected from nine countries (China, Pakistan, Italy, Egypt, Ethiopia, Canada, Mexico, Ecuador, and the U.S.) in 2010–2018 were genotyped using 14 codominant simple sequence repeat markers. A total of 433, including 333 new multi-locus genotypes (MLGs), were identified, which were clustered into ten molecular groups (MGs). The MGs and country-wise populations differed in genetic diversity, heterozygosity, and correlation coefficient between the marker and virulence data. Many isolates from different countries, especially the isolates from Mexico, Ecuador, and the U.S., were found to be identical or closely related MLGs, and some of the MGs were present in all countries, indicating Pst migrations among different countries. The analysis of molecular variance revealed 78% variation among isolates, 12% variation among countries, and 10% variation within countries. Only low levels of differentiation were found by the pairwise comparisons of country populations. Of the 10 MGs, 5 were found to be involved in sexual and/or somatic recombination. Identical and closely related MLGs identified from different countries indicated international migrations. The study provides information on the distributions of various Pst genetic groups in different countries and evidence for the global migrations, which should be useful in understanding the pathogen evolution and in stressing the need for continual monitoring of the disease and pathogen populations at the global scale.

Population Diversity, Dynamics, and Differentiation of Wheat Stripe Rust Pathogen Puccinia striiformis f. sp. tritici From 2010 to 2017 and Comparison With 1968 to 2009 in the United States

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is a serious disease on wheat in the United States, especially after 2000. In the present study, 2,247 Pst isolates collected over all stripe rust epidemiological regions in the United States from 2010 to 2017 were genotyped at 14 simple sequence repeat (SSR) loci to investigate the population diversity, dynamics, and differentiation. A total of 1,454 multilocus genotypes (MLGs) were detected. In general, the populations in the west (regions 1-6) had more MLGs and higher diversities than the populations in the east (regions 7-12). The populations of 2010 and 2011 were more different from the other years. Genetic variation was higher among years than among regions, indicating the fast changes of the population. The divergence (Gst) was bigger between the west population and east population than among regions within either the west or east population. Gene flow was stronger among the regional populations in the east than in the west. Clustering analyses revealed 3 major molecular groups (MGs) and 10 sub-MGs by combining the genotypic data of 2010-2017 isolates with those of 1968-2009. MG1 contained both 1968-2009 isolates (23.1%) and 2010-2017 isolates (76.9%). MG2 had 99.4% of isolates from 1968-2009. MG3, which was the most recent and distinct group, had 99.1% of isolates from 2010-2017. Of the 10 sub-MGs, 5 (MG1-3, MG1-5, MG3-2, MG3-3, and MG3-4) were detected only from 2011 to 2017. The SSR genotypes had a moderate, but significant correlation (r = 0.325; p < 0.0001) with the virulence phenotype data. The standard index values of association (rbarD = 0.11) based on either regional or yearly populations suggest clonal reproduction. This study indicated high diversity, fast dynamics, and various levels of differentiation of the Pst population over the years and among epidemiological regions, and the results should be useful for managing wheat stripe rust.

Sinusoidal analysis reveals a non-linear and dopamine-dependent relationship between ambient illumination and motor activity in larval zebrafish

Larval zebrafish show stereotyped motor responses to changes in ambient illumination. The responses can be evaluated in 96-well plates, and are used widely to assess neurological function in zebrafish models. However, the square-wave (on/off) light stimuli commonly employed in these studies do not allow analysis of the relationship between motor activity and illumination intensity or its rate of change. To address this limitation, we measured larval zebrafish motor function while ambient illumination was modulated sinusoidally. Motor activity varied robustly and reproducibly in antiphase with illumination. The relationship between mean swimming speed (dependent variable) and illuminance (independent variable) was described most closely by a power function, and was influenced dynamically by the proportional rate of change of illuminance. Several predictions from this model were verified experimentally by testing responses to sinusoidal illumination waveforms that were amplitude-, phase-, or offset-modulated, or transformed by a power function. At concentrations ≤5 μM, the dopamine D2 receptor inverse agonist haloperidol selectively abrogated the motor response to decreasing Illuminance without altering baseline activity in bright light, suggesting that dopamine is essential for illuminance-dependent motor function. These data contribute to understanding the environmental determinants of motor activity in zebrafish larvae, suggest experimental opportunities to elucidate underlying neural mechanisms, and potentially provide an assay of dopaminergic function for chemical and genetic screening applications.

PM2.5 exposure induces alveolar epithelial cell apoptosis and causes emphysema through p53/Siva-1

OBJECTIVE

This study aims to investigate whether PM2.5 exposure is involved in the induction of alveolar epithelial cell apoptosis and the progression of emphysema in mice, and to further explore its specific molecular mechanism.

MATERIALS AND METHODS

A certain number of PM2.5 exposed mice and normal control mice were selected, and a lung resection operation was performed to collect the pulmonary tissue samples, which were then analyzed by hematoxylin and eosin (H&E) staining assay. Subsequently, the total protein in the pulmonary tissues of mice in PM2.5 exposure group and control group was extracted, and the p53 protein level was detected by Western blot. Meanwhile, in A549 cells, after treatment of different doses of PM2.5, the protein levels of p53, caspase3, and clv-caspase3 were examined by Western blot while the mRNA levels of p53, Siva-1, and clv-caspase3 were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR), respectively. In addition, flow cytometry was carried out to measure the incidence of cell apoptosis, while chromatin immunoprecipitation (ChIP) assay was performed to verify whether p53 binds to the Siva-1 promoter region and thus regulates its transcription process.

RESULTS

H&E staining revealed that PM2.5 exposure caused pathological damage in the pulmonary tissues and the expansion of the spatial structure of alveoli, which led to emphysema in mice. Moreover, p53 protein expression in pulmonary tissue of mice in PM2.5 exposure group was remarkably higher than that in the control group. Subsequently, A549 cells were treated with 0, 25, 50, 100 μg/ml PM2.5 for 48 h, and it was found that, with the increase of PM2.5 exposure dose, the p53 protein level, Siva-1 mRNA level and cell apoptosis rate were all found increased in a dose-dependent manner, which could be partially reversed by transfection of si-p53 in A549 cells. In addition, CHIP experiments confirmed that p53 can bind to the Siva-1 promoter region and directly regulate Siva-1 transcription. In A549 cells, PM2.5 exposure increased the expression of the clv-caspase3 protein, which was reversed by the knockdown of p53; however, simultaneous overexpression of Siva-1 could further increase the clv-caspase3 protein level. Additionally, flow cytometry also revealed that PM2.5 exposure induced apoptosis of alveolar epithelial cells, while the knockdown of p53 reduced that, which could be promoted by the overexpression of Siva-1.

CONCLUSIONS

PM2.5 exposure can promote the transcription of Siva-1 to induce apoptosis of alveolar epithelial cells and accelerate the progression of emphysema in mice by enhancing p53 protein expression.

Increase in plasma Niemann-Pick disease type C2 protein is associated with poor prognosis of sepsis

The functional significance of extracellular Niemann-Pick disease type C2 protein (NPC2) is poorly defined. It is not known whether there is an association between plasma NPC2 and sepsis. Our exploratory, quantitative proteomic analysis showed a significant increase in the level of plasma NPC2 in moribund sepsis patients. Thus, we subsequently determined NPC2 concentration in plasma from healthy subjects, pneumonia patients and sepsis patients with comorbid pneumonia; and analyzed the association of plasma NPC2 with organ dysfunction and prognosis of sepsis patients. Our data shows that plasma NPC2 concentration was significantly higher in pneumonia and sepsis patients than healthy subjects, and was further increased in sepsis patients when the SOFA score reached 14. In addition, NPC2 concentration was significantly higher in patients that subsequently developed septic shock or died within 30 days. Moreover, NPC2 level showed the strongest association with the degree of renal dysfunction in sepsis patients. In moribund sepsis patients, however, NPC2 had highest correlation coefficient with indicators of coagulation anomaly. Based on these results, we conclude that the increase in plasma NPC2 in sepsis patients is associated with multiple organ failure, possibly results from a deficiency in renal clearance, and may serve as a prognostic marker for sepsis.

Constructing Scalable Superhydrophobic Membranes for Ultrafast Water-Oil Separation

Superhydrophobic membranes are desirable for separation of water-in-oil emulsions, membrane distillation, and membrane condensation. However, the lack of large-scale manufacture methods of superhydrophobic membranes hampers their widespread applications. Here, a facile method of coaxial electrospinning is provided to manufacture superhydrophobic membranes for the ultrafast separation of water-in-oil emulsions. Under the high-voltage electric field, the polydimethylsiloxane (PDMS)-coated polyvinylidene fluoride (PVDF) nanofibers and PDMS microspheres with PVDF nanobulges were integrated together during the electrospinning process. Moreover, asymmetric composite membranes with selective layers are designed to reduce the resistance of the mass transfer. Consequently, the as-prepared asymmetric composite membrane exhibits an ultrafast permeance and excellent separation efficiency of about 99.6%, outperforming most of the state-of-the-art membranes reported previously. Most importantly, the membrane could be as large as 770 cm², could be manufactured continuously, and could be easily enlarged further via tailoring the roller receptor, showing strong promise in the separation of water-in-oil emulsions.

Seizures are a druggable mechanistic link between TBI and subsequent tauopathy

Traumatic brain injury (TBI) is a prominent risk factor for dementias including tauopathies like chronic traumatic encephalopathy (CTE). The mechanisms that promote prion-like spreading of Tau aggregates after TBI are not fully understood, in part due to lack of tractable animal models. Here, we test the putative role of seizures in promoting the spread of tauopathy. We introduce ‘tauopathy reporter’ zebrafish expressing a genetically encoded fluorescent Tau biosensor that reliably reports accumulation of human Tau species when seeded via intraventricular brain injections. Subjecting zebrafish larvae to a novel TBI paradigm produced various TBI features including cell death, post–traumatic seizures, and Tau inclusions. Bath application of dynamin inhibitors or anticonvulsant drugs rescued TBI-induced tauopathy and cell death. These data suggest a role for seizure activity in the prion-like seeding and spreading of tauopathy following TBI. Further work is warranted regarding anti-convulsants that dampen post-traumatic seizures as a route to moderating subsequent tauopathy.

Traumatic brain injury can result from direct head concussions, rapid head movements, or a blast wave generated by an explosion. Traumatic brain injury often causes seizures in the short term and is a risk factor for certain dementias, including Alzheimer’s disease and chronic traumatic encephalopathy in the long term. A protein called Tau undergoes a series of chemical changes in these dementias that makes it accumulate, form toxic filaments and kill neurons.

The toxic abnormal Tau proteins are initially found only in certain regions of the brain, but they spread as the disease progresses. Previous studies in Alzheimer’s disease and other diseases where Tau proteins are abnormal suggest that Tau can spread between neighboring neurons and this can be promoted by neuron activity. However, scientists do not know whether similar mechanisms are at work following traumatic brain injury. Given that seizures are very common following traumatic brain injury, could they be partly responsible for promoting dementia?

To investigate this, researchers need animal models in which they can measure neural activity associated with traumatic brain injury and observe the spread of abnormal Tau proteins. Alyenbaawi et al. engineered zebrafish so that their Tau proteins would be fluorescent, making it possible to track the accumulation of aggregated Tau protein in the brain. Next, they invented a simple way to perform traumatic brain injury on zebrafish larvae by using a syringe to produce a pressure wave. After this procedure, many of the fish exhibited features consistent with progression towards dementia, and seizure-like behaviors.

The results showed that post-traumatic seizures are linked to the spread of aggregates of abnormal Tau following traumatic brain injury. Alyenbaawi et al. also found that anticonvulsant drugs can lower the levels of abnormal Tau proteins in neurons, preventing cell death, and could potentially ameliorate dementias associated with traumatic brain injury. These drugs are already being used to prevent post-traumatic epilepsy, but more research is needed to confirm whether they reduce the risk or severity of Tau-related neurodegeneration.

Frequency drift mitigation of Φ-OTDR using difference-fitting method

A difference-fitting method is proposed to mitigate the low frequency drift of a phase-sensitive optical time domain reflectometry (Φ-OTDR) system caused by laser phase noise. The effective difference region for phase demodulation is theoretically analyzed and experimentally verified, which should be greater than the convolution of the spatial resolution and the length of disturbed optical fiber. Then, a median-fitting algorithm is used to obtain the phase noise of the differential region. The vibration signal of 0.2 Hz is first demodulated with the SNR of 41.79 dB on the optical fiber of 11 km. The low-frequency vibration signals of 0.05 Hz and 0.02 Hz are then successfully restored by using the difference-fitting method, which can effectively eliminate the influence of low frequency drift.

[Influenza virus activates toll-like receptor 7/nuclear factor-κB signaling pathway to regulate airway inflammatory response in patients with acute exacerbation of chronic obstructive pulmonary diseases]

Objective: To explore how influenza A virus (IAV) regulates airway inflammation via activating Toll-like receptor 7(TLR7)/nuclear factor of κB (NF-κB) signaling pathway in patients with acute exacerbation of chronic obstructive pulmonary disease (COPD). Methods: Primary bronchial epithelial cells were isolated and cultured from normal controls and COPD patients. Samples were divided into 6 groups according to different in vitro treatment, including normal epithelial cell group (A), normal cells+IAV group (B), COPD epithelial cell group (C), COPD cells+IAV group (D), normal cells+TLR7 small interference RNA (si-RNA) group (E), COPD cells+TLR7 siRNA group (F). Protein expressions of TLR7 and NF-κB were detected by Western blot after 24h co-culture with IAV and TLR7 siRNA. Interleukin-6 (IL-6) and tumor necrosis factor α (TNF α) were detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Compared with group A [0.350±0.075 and 0.470±0.034, (53.000±6.532)pg/ml and (17.000±1.625)pg/ml],TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group B[0.950±0.075 and 1.090±0.078,(185.000±7.874)pg/ml and (32.000±0.838)pg/ml], group C[0.780±0.056 and 0.910±0.045,(138.000±5.100)pg/ml and 29.000±1.323)pg/ml) and group D[1.280±0.031 and 1.540±0.051,(432.000±5.734)pg/ml and (52.000±3.453)pg/ml] (all P<0.01). Compared with group C TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly increased in group D (P<0.01). (2) Compared with the group A[0.530±0.023 and 0.800±0.046,(51.000±0.327)pg/ml and (14.000±0.314)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels were significantly decreased in the group E[0.350±0.047 and 0.510±0.067,(26.000±1.081)pg/ml and(8.000±0.526)pg/ml] (P<0.05). Compared with group C[1.080±0.078 and 1.280±0.034,(125.000±2.249)pg/ml and (28.000±1.010)pg/ml], TLR7, NF-κB protein expression and IL-6, TNF α levels decreased in the group F[0.880±0.056 and 1.040±0.029,(83.000±1.125)pg/ml and (21.000±0.429)pg/ml] (P<0.05). Conclusion: Influenza viruses activate TLR7/NF-κB signaling pathway to regulate airway inflammation storms in patients with acute exacerbation of COPD. New therapeutic targets of acute exacerbation COPD may be studied based on these inflammation responses to influenza viruses.

α-Synuclein amplifies cytoplasmic peroxide flux and oxidative stress provoked by mitochondrial inhibitors in CNS dopaminergic neurons in vivo

Convergent evidence implicates impaired mitochondrial function and α-Synuclein accumulation as critical upstream events in the pathogenesis of Parkinson's disease, but comparatively little is known about how these factors interact to provoke neurodegeneration. We previously showed that α-Synuclein knockdown protected rat substantia nigra dopaminergic neurons from systemic exposure to the mitochondrial complex I inhibitor rotenone. Here we show that motor abnormalities prior to neuronal loss in this model are associated with extensive α-Synuclein-dependent cellular thiol oxidation. In order to elucidate the underlying events in vivo we constructed novel transgenic zebrafish that co-express, in dopaminergic neurons: (i) human α-Synuclein at levels insufficient to provoke neurodegeneration or neurobehavioral abnormalities; and (ii) genetically-encoded ratiometric fluorescent biosensors to detect cytoplasmic peroxide flux and glutathione oxidation. Live intravital imaging of the intact zebrafish CNS at cellular resolution showed unequivocally that α-Synuclein amplified dynamic cytoplasmic peroxide flux in dopaminergic neurons following exposure to the mitochondrial complex I inhibitors MPP⁺ or rotenone. This effect was robust and clearly evident following either acute or prolonged exposure to each inhibitor. In addition, disturbance of the resting glutathione redox potential following exogenous hydrogen peroxide challenge was augmented by α-Synuclein. Together these data show that α-Synuclein is a critical determinant of the redox consequences of mitochondrial dysfunction in dopaminergic neurons. The findings are important because the mechanisms underlying α-Synuclein-dependent reactive oxygen species fluxes and antioxidant suppression might provide a pharmacological target in Parkinson's disease to prevent progression from mitochondrial dysfunction and oxidative stress to cell death.

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Extensive neuronal thiol oxidation in a rat PD model is α-Synuclein-dependent.

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Peroxide flux and glutathione oxidation can be imaged in live transgenic zebrafish.

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α-Synuclein amplifies cytosolic peroxide flux in dopaminergic neurons.

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α-Synuclein exacerbates dynamic disturbances of the glutathione redox potential.

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The underlying molecular mechanisms may provide therapeutic targets in PD.

Pyrene[4,5-d]imidazole-Based Derivatives with Hybridized Local and Charge-Transfer State for Highly Efficient Blue and White Organic Light-Emitting Diodes with Low Efficiency Roll-Off

A family of pyrene[4,5-d]imidazole derivatives, PyPA, PyPPA, PyPPAC, and PyPAC, with different excited states are successfully developed. Among them, PyPPA and PyPPAC possess hybridized local and charge-transfer (HLCT) state, endowing them with pure blue fluorescence as well as high quantum yields. The nondoped organic light-emitting diode (OLED) based on PyPPA displays Commission Internationale de L'Eclairage coordinates of (0.14, 0.13) and achieves a maximum external quantum efficiency (EQE) of 8.47%, which are among the highest value reported to date for nondoped blue HLCT OLEDs. The nondoped OLED based on PyPPAC exhibits a maximum luminance of 50,046 cd m^-2 located in the blue region with CIE coordinates of (0.15, 0.21) and an EQE of 6.74% even when the luminance reached over 10,000 cd m^-2. In addition, they both reveal ultimate exciton utilizing efficiencies of nearly 100%. The potential of a blue emitter of PyPPA with an HLCT character for application in white OLED (WOLED) is further tested. The efficient two-color hybrid warm WOLED is successfully achieved, which provides the total EQE, power efficiency, and current efficiency of up to 21.19%, 61.46 lm W^-1, and 62.13 cd A^-1, respectively. The nondoped blue OLEDs and hybrid WOLEDs present good color stabilities with low efficiency roll-offs. Our results prove that taking advantage of the HLCT state, nondoped blue OLEDs as well as hybrid WOLEDs with high performance could be realized, which have a promising prospect for the displays and lightings in the future.

Molecular Characterization of International Collections of the Wheat Stripe Rust Pathogen Puccinia striiformis f. sp. tritici Reveals High Diversity and Intercontinental Migration

Puccinia striiformis f. sp. tritici causes stripe rust (yellow rust), one of the most important wheat diseases worldwide. To understand the genetic variation of the pathogen in a global scale, 283 P. striiformis f. sp. tritici isolates collected from 16 countries in eight geographic regions were genotyped using 24 codominant simple sequence repeat markers. The overall collection had a high level of genetic diversity, and the diversity levels in the Asian populations were generally higher than those of the other regions. Heterozygosity of isolates ranged from 0 to 75%, with an average of 46%. Mean heterozygosity in individual countries ranged from 34 to 59%. A total of 265 multilocus genotypes (MLGs) were detected, which were classified into eight molecular groups. Some of the molecular groups were present in all geographic regions. Moreover, many isolates from different regions were found to be identical or very closely related MLGs. Analysis of molecular variance revealed high variation within countries and intermediate variation between countries, but it revealed low and insignificant variation among geographic regions. Pairwise comparisons of regional populations detected considerable effective migrants and only low to moderate levels of differentiation. The molecular genotypes had a moderate level of correlation with the virulence phenotypes, and some of the molecular/virulence groups contained isolates from different continents. The results indicate tremendous migrations of P. striiformis f. sp. tritici and warrant the development of management strategies considering the global pathogen population.

Chemoptogenetic ablation of neuronal mitochondria in vivo with spatiotemporal precision and controllable severity

Mitochondrial dysfunction is implicated in the pathogenesis of multiple neurological diseases, but elucidation of underlying mechanisms is limited experimentally by the inability to damage specific mitochondria in defined neuronal groups. We developed a precision chemoptogenetic approach to target neuronal mitochondria in the intact nervous system in vivo. MG2I, a chemical fluorogen, produces singlet oxygen when bound to the fluorogen-activating protein dL5** and exposed to far-red light. Transgenic zebrafish expressing dL5** within neuronal mitochondria showed dramatic MG2I- and light-dependent neurobehavioral deficits, caused by neuronal bioenergetic crisis and acute neuronal depolarization. These abnormalities resulted from loss of neuronal respiration, associated with mitochondrial fragmentation, swelling and elimination of cristae. Remaining cellular ultrastructure was preserved initially, but cellular pathology downstream of mitochondrial damage eventually culminated in neuronal death. Our work provides powerful new chemoptogenetic tools for investigating mitochondrial homeostasis and pathophysiology and shows a direct relationship between mitochondrial function, neuronal biogenetics and whole-animal behavior.

Astrocyte-specific DJ-1 overexpression protects against rotenone-induced neurotoxicity in a rat model of Parkinson's disease

DJ-1 is a redox-sensitive protein with several putative functions important in mitochondrial physiology, protein transcription, proteasome regulation, and chaperone activity. High levels of DJ-1 immunoreactivity are reported in astrocytes surrounding pathology associated with idiopathic Parkinson's disease, possibly reflecting the glial response to oxidative damage. Previous studies showed that astrocytic over-expression of DJ-1 in vitro prevented oxidative stress and mitochondrial dysfunction in primary neurons. Based on these observations, we developed a pseudotyped lentiviral gene transfer vector with specific tropism for CNS astrocytes in vivo to overexpress human DJ-1 protein in astroglial cells. Following vector delivery to the substantia nigra and striatum of adult Lewis rats, the DJ-1 transgene was expressed robustly and specifically within astrocytes. There was no observable transgene expression in neurons or other glial cell types. Three weeks after vector infusion, animals were exposed to rotenone to induce Parkinson's disease-like pathology, including loss of dopaminergic neurons, accumulation of endogenous α-synuclein, and neuroinflammation. Animals over-expressing hDJ-1 in astrocytes were protected from rotenone-induced neurodegeneration, and displayed a marked reduction in neuronal oxidative stress and microglial activation. In addition, α-synuclein accumulation and phosphorylation were decreased within substantia nigra dopaminergic neurons in DJ-1-transduced animals, and expression of LAMP-2A, a marker of chaperone mediated autophagy, was increased. Together, these data indicate that astrocyte-specific overexpression of hDJ-1 protects neighboring neurons against multiple pathologic features of Parkinson's disease and provides the first direct evidence in vivo of a cell non-autonomous neuroprotective function of astroglial DJ-1.

Visual and Colorimetric High-Throughput Analysis of Chiral Carboxylic Acids Based on Enantioselective Charge Shielding of Gold Nanoparticles

Because chiral carboxylic acids (CCAs) are a class of important biological molecules and common functional moieties found in pharmaceutical molecules, the chiral analysis of CCAs has received much attention. Herein, we developed a simple, rapid, and cost-effective method for visual and colorimetric high-throughput analysis of CCAs using chiral di-imine structure-modified gold nanoparticles (C-AuNPs) as the probe. The C-AuNPs are positively charged in the presence of zinc ion, and they can be enantioselectively shielded by the negatively charged CCA enantiomers. Therefore, upon the addition of different concentrations and enantiomeric excess (ee) of CCAs, the C-AuNP-based sensor shows the different levels of aggregation along with the visual changes in solution color, which can achieve simultaneous analysis of the concentration and ee of CCAs. The chiral recognition mechanism based on C-AuNPs was investigated by the determination of binding constants ( K) and molecular simulation methods. Our approach is expected to have the wide-ranging applications in the developing region for enantio-sensing of various chiral drugs and biomolecules.