Rice OsANN9 Enhances Drought Tolerance through Modulating ROS Scavenging Systems.

Drought is a critical abiotic stress which leads to crop yield and a decrease in quality. Annexins belong to a multi-gene family of calcium- and lipid-binding proteins and play diverse roles in plant growth and development. Herein, we report a rice annexin protein, OsANN9, which in addition to regular annexin repeats and type-II Ca2+ binding sites, also consists of a C2H2-type zinc-finger domain. We found that the expression of OsANN9 was upregulated by polyethylene glycol (PEG) or water-deficient treatment. Moreover, plants that overexpressed OsANN9 had increased survival rates under drought stress, while both OsANN9-RNAi and osann9 mutants showed sensitivity to drought. In addition, the overexpression of OsANN9 increased superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities, which regulate reactive oxygen species homeostasis. Collectively, these findings indicate that OsANN9 may function as a positive regulator in response to drought stress by modulating antioxidant accumulation. Interestingly, the setting rates of osann9 mutant rice plants significantly decreased in comparison to wild-type plants, suggesting that OsANN9 might be involved in other molecular mechanisms in the rice seed development stage.

Grapevine bZIP transcription factor bZIP45 regulates VvANN1 and confers drought tolerance in Arabidopsis.

Drought is a severe environmental condition that restricts the vegetative growth and reduces the yield of grapevine (Vitis vinifera L.). However, the mechanisms underlying grapevine response and adaptation to drought stress remain unclear. In the present study, we characterized an ANNEXIN gene, VvANN1, which plays a positive role in the drought stress response. The results indicated that VvANN1 was significantly induced by osmotic stress. Expression of VvANN1 in Arabidopsis thaliana enhanced osmotic and drought tolerance through modulating the level of MDA, H2O2, and O2 ·- at the seedling stage, implying that VvANN1 might be involved in the process of ROS homeostasis under drought or osmotic stress conditions. Moreover, we used yeast one-hybridization and chromatin immunoprecipitation assays to show that VvbZIP45 could regulate VvANN1 expression by directly binding to the promoter region of VvANN1 in response to drought stress. We also generated transgenic Arabidopsis that constitutively expressed the VvbZIP45 gene (35S::VvbZIP45) and further produced VvANN1Pro::GUS/35S::VvbZIP45 Arabidopsis plants via crossing. The genetic analysis results subsequently indicated that VvbZIP45 could enhance GUS expression in vivo under drought stress. Our findings suggest that VvbZIP45 may modulate VvANN1 expression in response to drought stress and reduce the impact of drought on fruit quality and yield.

Pyogranulomatous dermatitis with Enterococcus faecalis in a spotted seal (Phoca larga).

BACKGROUND: Cutaneous infections are important diseases in captive and free-ranging pinnipeds and are associated with various causative agents. Some special agents, such as fungi, morbillivirus and mycobacteria, can cause cutaneous specific granulomatous inflammation. OBJECTIVES: To identity the cause of chronic dermatitis in a spotted seal in an aquarium. METHODS: Herein, we analyze the clinical history and cutaneous samples of the spotted seal through differential diagnosis (histopathology, microorganism culture, special histochemical staining methods, PCR), and antibiotic susceptibility test. RESULTS: This is a rare pyogranulomatous dermatitis case caused by E. faecalis in a captive adult male spotted seal (Phoca largha) in an aquarium. CONCLUSIONS: We provide a meaningful approach to the diagnosis and treatment of bacterial dermatitis in pinnipeds.

Methods for Assessment of the Glomerular Filtration Rate in Laboratory Animals.

Background: The glomerular filtration rate (GFR), as the benchmark of renal function, has been widely used in clinical practice and basic medical research. Currently, most researchers still rely on endogenous markers, such as plasma creatinine, blood urea nitrogen, and cystatin C, to evaluate renal function in laboratory animals. While inexpensive and simple to use, methods based on endogenous markers are often inaccurate and susceptible to several internal physiological factors. Thus, it is necessary to establish a method to precisely assess the GFR, especially when detecting early changes in GFR during acute kidney injury, and hyperfiltration usually caused by pregnancy or diabetic nephropathy. In addition, laboratory animals have higher tolerance for invasive procedures than humans, allowing novel technologies to be applied on them for GFR monitoring. In recent years, significant progress has been made in developing new methods to assess GFR in animals. However, no publication has reviewed these techniques. Summary: This article summarized the majority of methods used to assess the GFR in animals in recent decades and discussed their working principles, workflows, advantages, and limitations, providing a wealth of reference and information for researchers interested in studying the kidney function in animals and developing techniques to monitor the GFR.

Sarcoptic mange is an emerging threat to biodiversity in the Qinling Mountains in China.

Sarcoptic mange, a disease caused by the burrowing mite Sarcoptes scabiei, is globally endemic and an emerging threat to wildlife. Although many studies have shown that wildlife diseases play key roles in biodiversity conservation, knowledge about sarcoptic mange is still insufficient. In this study, we aim to improve the understanding of the impacts of sarcoptic mange on wildlife populations, the mechanisms involved in its eco-epidemiology and the associated risks to public and ecosystem health by investigating mass death events in gorals and serows in the Qinling Mountains. We conducted interviews with practitioners and local people in the central Qinling Mountains. From the same locations, we collected 24 cutaneous samples from various animals and surveillance data from infrared cameras. Pathological, parasitological and microbiological examinations of the samples were performed. Mite-induced cutaneous lesions, mites and eggs were observed in samples from dead gorals and one dead serow but not in other species. Molecular analysis confirmed the mites to be S. scabiei and shared the same cox 1 genotype. The data obtained from the interviews and infrared cameras indicated that the death of wildlife was related to sarcoptic mange infection and that there had been a decrease in the goral population since the outbreak of the disease. We confirmed that sarcoptic mange was the major cause of the mass death events and may have spread from the western to eastern Qinling Mountains. Based on our findings, we propose several protection strategies to help preserve biodiversity in the Qinling Mountains.

Feline herpesvirus infection and pathology in captive snow leopard.

Feline herpesvirus type 1 (FHV-1) is a common causative agent of domestic cats' rhinotracheitis in domestic cats, and it increasingly threatens wild felids worldwide. The endangered snow leopard (Panthera uncia) belongs to the family Felidae, and it is the top predator on the Tibetan Plateau. Here we report the identification and isolation of FHV-1 from three dead captive snow leopards that presented with sneezing and rhinorrhea. To explore the relationship between FHV-1 and their deaths, organs and nasal swabs were collected for histopathology, viral isolation and sequence analysis. The results revealed that all three snow leopards were infected with FHV-1. The first animal died primarily of cerebral infarction and secondary non-suppurative meningoencephalitis that was probably caused by FHV-1. The second animal died mainly of renal failure accompanied by interstitial pneumonia caused by FHV-1. The cause of death for the third animal was likely related to the concurrent reactivation of a latent FHV-1 infection. The gD and gE gene sequence alignment of the isolated FHV-1 isolate strain revealed that the virus likely originated from a domestic cat. It was found that FHV-1 infection can cause different lesions in snow leopards than in domestic cats and is associated with high risk of disease in wild felids. This suggests that there should be increased focus on protecting wild felids against FHV-1 infections originating from domestic cats.

H3K36 demethylase JMJ710 negatively regulates drought tolerance by suppressing MYB48-1 expression in rice.

The homeostasis of histone methylation is maintained by histone methyltransferases and demethylases, which are important for the regulation of gene expression. Here, we report a histone demethylase from rice (Oryza sativa), Jumonji C domain-containing protein (JMJ710), which belongs to the JMJD6 group and plays an important role in the response to drought stress. Overexpression of JMJ710 causes a drought-sensitive phenotype, while RNAi and clustered regularly interspaced short palindromic repeats (CRISPR)-knockout mutant lines show drought tolerance. In vitro and in vivo assays showed that JMJ710 is a histone demethylase. It targets to MYB TRANSCRIPTION FACTOR 48 (MYB48-1) chromatin, demethylates H3K36me2, and negatively regulates the expression of MYB48-1, a positive regulator of drought tolerance. Under drought stress, JMJ710 is downregulated and the expression of MYB48-1 increases, and the subsequent activation of its downstream drought-responsive genes leads to drought tolerance. This research reports a negative regulator of drought stress-responsive genes, JMJ710, that ensures that the drought tolerance mechanism is not mis-activated under normal conditions but allows quick activation upon drought stress.

Mechanochemical prepared ibuprofen-Polygonatum sibiricum polysaccharide drug delivery system for enhanced bioactivity with reduced renal injury induced by NSAIDs.

Ibuprofen (IBU) was a widely used NSAID (a type of nonsteroidal anti-inflammatory drug) worldwide, and many drug deliveries had been reported to enhance bioavailability. However, higher bioavailability would increase the danger of renal injury caused by oxidative stress. This study prepared IBU-Polygonatum sibiricum polysaccharide (IBU-PSP) drug delivery system via mechanochemical method. Due to drug delivery and renal protection effect of Polygonatum sibiricum polysaccharide (PSP), the solubility of IBU-PSP was increased 8.22 times, and the bioavailability was increased 2.52 times compared with IBU, carrageenin-induced rat paw edema test also increased. Meanwhile, short-term and long-term renal injuries induced by IBU were notable decreases. In conclusion, IBU-PSP was a multifunctional drug delivery system with superior anti-inflammatory and renal protection effects. It will benefit from developing high-efficiency NADIs preparations with safer clinical applications while providing an efficient and energy-saving technology for polysaccharide drug delivery.

Quasi-Parallel NiFe Layered Double Hydroxide Nanosheet Arrays for Large-Current-Density Oxygen Evolution Electrocatalysis.

Designing advanced electrocatalysts for oxygen evolution at large current density (>500 mA cm-2 ) is critical to practical water splitting applications. Herein, a novel quasi-parallel NiFe layered double hydroxide (NiFe LDH) nanosheet arrays with pattern alignment on Ni foam was developed. The initial α-Ni(OH)2 layer induced effective coprecipitation between Ni2+ and Fe3+ for the formation of LDH phase, guaranteeing the electronic pulling effect among metal cations and enhancing the interaction between active materials and substrate for excellent adhesion and electrical conductivity. Quasi-parallel NiFe LDH nanoarrays exhibited outstanding oxygen evolution activity with a small Tafel slope of 30.1 mV dec-1 and overpotentials of 196, 255, and 284 mV at a current density of 10, 500, and 1000 mA cm-2 in 1.0 m KOH solution, respectively, and high stability over 40 h at 750 mA cm-2 . This work presents a new strategy towards fabricating electrode materials with exceptional performance.

The bHLH transcription factor regulated gene OsWIH2 is a positive regulator of drought tolerance in rice.

Drought is a major abiotic stress limiting crop growth and yield. In this study, we characterized a novel drought tolerance induced WIH gene in rice, OsWIH2. Overexpression of OsWIH2 in rice resulted in significantly higher drought tolerance, probably due to the decreased water loss rate and reactive oxygen species (ROS) accumulation under drought stress. We identified a long-chain fatty acid HOTHEAD (HTH) that interacted with OsWIH2 using yeast two-hybrid screening. OsWIH2 is an enzyme which is involved in fatty acid synthesis. We further demonstrated that the drought-inducible bHLH transcription factor OsbHLH130 could activate the expression of OsWIH2. Overall, our results suggest that drought stress may induce OsbHLH130 accumulation, which in turn activates OsWIH2 expression, and the latter improves rice drought tolerance by participating in cuticular wax biosynthesis and reducing the water loss rate as well as ROS accumulation. This research provides new genes for crop improvement.

OsANN4 modulates ROS production and mediates Ca2+ influx in response to ABA.

BACKGROUND: Plant annexins are calcium- and lipid-binding proteins that have multiple functions, and a significant amount of research on plant annexins has been reported in recent years. However, the functions of annexins in diverse biological processes in rice are largely unclear. RESULTS: Herein, we report that OsANN4, a calcium-binding rice annexin protein, was induced by abscisic acid (ABA). Under ABA treatment, the plants in which OsANN4 was knocked down by RNA interference showed some visible phenotypic changes compared to the wild type, such as a lower rooting rate and shorter shoot and root lengths. Moreover, the superoxide dismutase (SOD) and catalase (CAT) activities of the RNAi lines were significantly lower and further resulted in higher accumulation of O2.- and H2O2 than those of the wild-type. A Non-invasive Micro-test Technology (NMT) assay showed that ABA-induced net Ca2+ influx was inhibited in OsANN4 knockdown plants. Interestingly, the phenotypic differences caused by ABA were eliminated in the presence of LaCl3 (Ca2+ channel inhibitor). Apart from this, we demonstrated that OsCDPK24 interacted with and phosphorylated OsANN4. When the phosphorylated serine residue of OsANN4 was substituted by alanine, the interaction between OsANN4 and OsCDPK24 was still observed, however, both the conformation of OsANN4 and its binding activity with Ca2+ might be changed. CONCLUSIONS: OsANN4 plays a crucial role in the ABA response, partially by modulating ROS production, mediating Ca2+ influx or interacting with OsCDPK24.

A novel outer membrane ß-1,6-glucanase is deployed in the predation of fungi by myxobacteria.

Myxobacterial predation on bacteria has been investigated for several decades. However, their predation on fungi has received less attention. Here, we show that a novel outer membrane ß-1,6-glucanase GluM from Corallococcus sp. strain EGB is essential for initial sensing and efficient decomposition of fungi during predation. GluM belongs to an unstudied family of outer membrane ß-barrel proteins with potent specific activity up to 24,000 U/mg, whose homologs extensively exist in myxobacteria. GluM was able to digest fungal cell walls efficiently and restrict Magnaporthe oryzae infection of rice plants. Genetic complementation with gluM restored the fungal predation ability of Myxococcus xanthus CL1001, which was abolished by the disruption of gluM homolog oar. The inability to prey on fungi with cell walls that lack ß-1,6-glucans indicates that ß-1,6-glucans are targeted by GluM. Our results demonstrate that GluM confers myxobacteria with the ability to feed on fungi, and provide new insights for understanding predator-prey interactions. Considering the attack mode of GluM, we suggest that ß-1,6-glucan is a promising target for the development of novel broad-spectrum antifungal agents.

Transformation of the θ-phase in Mg-Li-Al alloys: a density functional theory study.

In Mg-Li-Al alloys, θ-phase MgAlLi(2) is a strengthening and metastable phase which is liable to be transformed to the equilibrium phase AlLi on overaging. While the structural details of the θ-phase MgAlLi(2) and the microscopic transformation are still unknown. In this paper, the structure of MgAlLi(2) unit cell was determined through X-ray powder diffraction simulation. Microscopic transformation process of θ-phase MgAlLi(2) was discussed in detail using first principles method.

Degradation of inhibitory substances by heterotrophic microorganisms during bioleaching of heavy metals from anaerobically digested sewage sludge.

The presence of organic acids was found to be inhibitory to the bioleaching of sewage sludge and the objective of the present study was to elucidate the roles of heterotrophic microorganisms in removing organic acids during the bioleaching of heavy metals from anaerobically digested sewage sludge. Microbiological analysis showed that acetic and propionic acids posed a severe inhibitory effect on iron-oxidizing bacteria as reflected by a sharp decrease in their viable counts in the first 4d and it only started to increase 2d after the depletion of both acids. Biodegradation of these inhibitory organic acids was revealed by sharp increases in total fungi and acidophiles between day 3 and day 5 which coincided with degradation of organic acids. This was further confirmed by the increases in total counts of both acetate and propionate degraders in the same period. Two yeast strains Y4 and Y5 with strong ability to degrade acetate and/or propionate were isolated and identified as Pichia sp. and Blastoschizomycetes capitatus, respectively. B. capitatus Y5 was an more important player in removing the inhibitory organic acids during the bioleaching process since it could utilize both acetate and propionate as sole carbon source while Pichia sp. Y4 was an strict acetate degrader. Results from the present study not only provided the evidence for biodegradation of organic acids by heterotrophs, but also disclosed a biological mechanism for the initiation of bioleaching of organic acid-laden sewage sludge.

Diversity of organophosphorus pesticide-degrading bacteria in a polluted soil and conservation of their organophosphorus hydrolase genes.

Seven methyl parathion-degrading bacteria were isolated from a long-term methyl parathion contaminated soil and were found to belong to the genera Pseudaminobacter, Achromobacter, Brucella, and Ochrobactrum. Southern blot analysis using an mpd gene probe revealed that their hydrolase genes were similar to the mpd gene from Plesiomonas sp. strain M6 and were all located on the chromosome. Gene libraries were constructed from genomic DNA of each of the 7 organophosphorus pesticide-degrading bacteria, and their mpd genes were cloned and sequenced. Sequence analysis revealed that their hydrolase genes were conserved, and that the G+C content of the mpd genes were distinctly different from that of the chromosome-located 16S rRNA gene, suggesting that the mpd gene could be transferred and expressed among a variety of bacterial hosts.

Identification of inhibitory substances affecting bioleaching of heavy metals from anaerobically digested sewage sludge.

Significant inhibitory effects of the filtrate medium of anaerobically digested sewage sludge on iron oxidation by Acidithiobacillus ferrooxidans ANYL-1 were observed in our preliminary experiments, indicating the presence of inhibitory substances in anaerobically digested sewage sludge. The objectives of the present study were to identify the possible inhibitory substances and to evaluate their impacts on metal solubilization during bioleaching of sewage sludge. The results showed that the concentrations of total reducing sugars, all tested metal ions, and anions were too low to suppress iron oxidation, and only organic acids, especially acetic and propionic acids, were found at concentrations higher than their inhibitory levels. The presence of 10.8 mM acetic acid and 9.88 mM propionic acid in sewage sludge (sludge N) led to long lag periods of 6 and 7 days for solubilization of Cu and Cr, respectively, as compared to a lag period of only 1 day in the control and another sludge (sludge S) with a low level of organic acids. Meanwhile the leaching time for maximum solubilization of Zn also extended to 6 days in the presence of organic acids as compared to 3 days in the control. Acetic and propionic acids posed an unfavorable bioleaching condition for anaerobically digested sewage sludge; therefore, further studies are required to explore the means to remove the inhibitory effects to improve the heavy metal bioleaching efficiency.