Involvement of brassinosteroids and abscisic acid in spikelet degeneration in rice under soil drying during meiosis.

Spikelet degeneration in rice (Oryza sativa L.) is a serious physiological defect, and can be regulated by soil moisture status and phytohormones. This study investigated the possibility that brassinosteroids (BRs) in collaboration with abscisic acid (ABA) are involved in mediating the effect of soil drying during meiosis on spikelet degeneration in rice. Three rice cultivars were field grown and three irrigation regimes including well watered (WW), moderate soil drying (MD), and severe soil drying (SD) were imposed during meiosis. MD significantly decreased spikelet degeneration in comparison with WW, due mainly to the alleviation in oxidative damage via enhancing ascorbate-glutathione (AsA-GSH) cycle activity in young panicles, and SD exhibited the opposite effects. Enhanced AsA-GSH cycle strength, decreased oxidative stress, and spikelet degeneration rate were closely associated with the synergistically elevated BR and ABA levels in young panicles in MD. In contrast, low BR and excessive ABA levels led to an increase in spikelet degeneration in SD. The three cultivars exhibited the same tendencies. The intrinsic link among AsA-GSH cycle, oxidative stress, spikelet degeneration rate, and BR and ABA levels was further verified by using transgenic rice lines and chemical regulators. BRs or ABA play a unique role in regulating spikelet degeneration. Synergistically increased BR and ABA levels in MD could work together to strengthen AsA-GSH cycle activity, leading to a reduction in oxidative damage and spikelet degeneration. On the other hand, a severe imbalance between low BR and excessive ABA levels may have contributed to the opposite effects in SD.

The sucrose transport regulator OsDOF11 mediates cytokinin degradation during rice development.

Photosynthetic tissues are dynamic structures whose homeostasis depends on the coordination of two antagonistic processes: self-maintenance and supporting sink tissues. The balance of these processes determines plant development, which might be mediated by cytokinin. However, little is known about the link between sucrose transport signaling and cytokinin. Rice (Oryza sativa) DNA BINDING WITH ONE FINGER11 (OsDOF11) is a transcription factor that mediates sucrose transport by inducing the expression of sucrose transporter genes. Here, we found that OsDOF11 loss-of-function mutants showed a semi-dwarf phenotype with a smaller cell length due to increased cytokinin content in source tissues. RNA sequencing and reverse transcription quantitative PCR analyses revealed that genes involved in cytokinin signaling and metabolism were affected in osdof11 mutants. Yeast one-hybrid, dual-luciferase reporter, and chromatin immunoprecipitation experiments showed that OsDOF11 directly binds to the promoter regions of O. sativa CYTOKININ OXIDASE/DEHYDROGENASE4 (OsCKX4). Moreover, mutation of osckx4 in the osdof11 osckx4 double mutant rescued the semi-dwarf phenotype of the osdof11 mutant. Interestingly, exogenous application of kinetin promoted OsDOF11 expression earlier than OsCKX4, and overexpression of O. sativa VIN3-LIKE 2 caused an increase in active cytokinin levels and induced OsDOF11 transcript levels. Taken together, our results suggest a model in which both a sucrose transport regulator (OsDOF11) and cytokinin via OsCKX4 establish a feedback loop to maintain dynamic tissue homeostasis.

Brassinosteroids mediate moderate soil-drying to alleviate spikelet degeneration under high temperature during meiosis of rice.

This study tested the hypothesis that brassinosteroids (BRs) mediate moderate soil-drying (MD) to alleviate spikelet degeneration under high temperature (HT) stress during meiosis of rice (Oryza sativa L.). A rice cultivar was pot-grown and subjected to normal temperature (NT) and HT treatments during meiosis, and two irrigation regimes including well-watered (WW) and MD were imposed to the plants simultaneously. The MD effectively alleviated the spikelet degeneration and yield loss under HT stress mainly via improving root activity and canopy and panicle traits including higher photosynthetic capacity, tricarboxylic acid cycle activity, and antioxidant capacity than WW. These parameters were regulated by BRs levels in plants. The decrease in BRs levels at HT was due mainly to the enhanced BRs decomposition, and the MD could rescue the BRs deficiency at HT via enhancing BRs biosynthesis and impeding decomposition. The connection between BRs and HT was verified by using rice BRs-deficient mutants, transgenic rice lines, and chemical regulators. Similar results were obtained in the open-air field experiment. The results suggest that BRs can mediate the MD to alleviate spikelet degeneration under HT stress during meiosis mainly via enhancing root activity, canopy traits, and young panicle traits of rice.

Overlapping peak separation algorithm for ion mobility spectra based on multistrategy JAYA.

RATIONALE: In the field of separation science, ion mobility spectrometry (IMS) plays an important role as an analytical tool. However, the lack of sufficient structural resolution is a common problem in qualitative and quantitative analysis using IMS. A method is needed to solve the problem of overlapping peaks caused by insufficient resolution. METHODS: The method uses multiple strategies to more effectively use population information to balance exploration and exploitation capabilities, prevent local optimization, accurately resolve overlapping peaks, quickly obtain optimal spectral peak model coefficients, and accurately identify compounds. RESULTS: Multistrategy JAYA algorithm's (MSJAYA) performance is compared with improved particle swarm optimization (IPSO), dynamic inertia weight particle swarm optimization (DIWPSO), and multiobjective dynamic teaching-learning-based optimization (MDTLBO). The analysis shows that MSJAYA's maximum separation error is within 0.6%, a level of accuracy not guaranteed by the other algorithms. In addition, the separation error fluctuates within a much smaller range, demonstrating MSJAYA's superior robustness. CONCLUSIONS: Compared with other overlapping peak separation algorithms, MSJAYA is more applicable because no special parameters are used. The method allows fast deconvolution analysis of strong overlapping peaks with multiple components, which greatly improves the resolution of IMS.

Tri-n-butyl phosphate delays tissue repair by dysregulating neutrophil function in zebrafish.

Tri-n-butyl phosphate (TnBP) is a widely used organophosphate ester, but its effects on the regenerative process under damaging circumstances remain unknown. In the present study, zebrafish larvae were exposed to 0, 50, 100, 200 and 1000 µg/L TnBP, and the caudal fins were cut at 72 hours post fertilization (hpf). First, after exposure to TnBP, the number of total neutrophils decreased together with decreased neutrophils in the tail, and TnBP inhibited chemotaxis. Second, reactive oxygen species (ROS) levels in the zebrafish decreased greatly. Following exposure to TnBP, transcription levels of many genes regulating fin regeneration, such as fgf20a, fgfr1a, bmp2a and bmp4, were significantly downregulated, while inflammatory factors such as cxcl8a, cxcl18b, il-6, and tnfa were abnormally upregulated. In addition, TnBP inhibited the regenerative area after caudal fin amputation. The inflammatory state was adverse during the regenerative process. In summary, TnBP exposure is immunotoxic and decreases oxidative stress in injured zebrafish larvae.

The Relationships among "STAY-GREEN" Trait, Post-Anthesis Assimilate Remobilization, and Grain Yield in Rice (Oryza sativa L.).

The mobilization and translocation of carbohydrates and mineral nutrients from vegetative plant parts to grains are pivotal for grain filling, often involving a whole plant senescence process. Loss of greenness is a hallmark of leaf senescence. However, the relationship between crop yield and senescence has been controversial for many years. Here, in this study, the overexpression and RNA interference lines of gene of OsNYC3 (Non-Yellow Coloring 3), a chlorophyll catabolism gene, were investigated. Furthermore, exogenous phytohormones were applied, and a treatment of alternate wetting and moderate drying (AWMD) was introduced to regulate the processes of leaf senescence. The results indicated that the delayed senescence of the "STAY-GREEN" trait of rice is undesirable for the process of grain filling, and it would cause a lower ratio of grain filling and lower grain weight of inferior grains, because of unused assimilates in the stems and leaves. Through the overexpression of OsNYC3, application of exogenous chemicals of abscisic acid (ABA), and water management of AWMD, leaf photosynthesis was less influenced, a high ratio of carbohydrate assimilates was partitioned to grains other than leaves and stems as labeled by 13C, grain filling was improved, especially for inferior spikelets, and activities of starch-synthesizing enzymes were enhanced. However, application of ethephon not only accelerated leaf senescence, but also caused seed abortion and grain weight reduction. Thus, plant senescence needs to be finely adjusted in order to make a contribution to crop productivity.

Effects of application of rapeseed cake as organic fertilizer on rice quality at high yield level.

BACKGROUND: Applying organic fertilizer coupled with chemical fertilizer has been widely adopted to improve crop productivity and quality and develop sustainable agriculture. However, little information is available about the effects of organic fertilizer on the grain quality of rice (Oryza sativa L.), especially nutritional quality and starch quality. In the present study, high yielding 'super' rice cultivars were grown in the field with three cultivation practices, including zero nitrogen application (0N), local high yielding practice with chemical fertilizer (T1) and T1 treatment with additional organic fertilizer (T2). RESULTS: Application of organic fertilizer synergistically improved rice production, nitrogen use efficiency, milling and appearance quality, and nutritional quality, including the contents of glutelin, essential amino acids and microelements, and also increased amylopectin and the ratio of the short chain of amylopectin, leading to a reduction in relative crystallinity, and decreased prolamin content. Application of organic fertilizer also increased the viscosity and breakdown values, whereas it decreased the pasting temperature and gelatinization enthalpy, resulting in better cooking and eating quality. CONCLUSION: Overall, application of organific fertilizer could synergistically improve nitrogen use efficiency and grain quality, including the structure and physicochemical properties of starch, contents of high value protein and amino acids, contents of microelements, and cooking and eating quality. © 2021 Society of Chemical Industry.

Leaf characteristics of rice cultivars with a stronger yield response to projected increases in CO2 concentration.

Rising levels of atmospheric carbon dioxide (CO2 ) could, potentially, be exploited as a means to increase seed yield and maintain food security, especially for cereal grains. Although there have been multiple cultivar trials indicating that significant yield variation occurs, the basis for these differences has not been entirely elucidated. Here, we focus on two rice cultivars that differed in field trials to their yield sensitivity to elevated CO2 : Yangdao6hao (YD6), and Wuyunjing23 (W23) to assess whether observed yield differences (YD6 > W23) were associated with concurrent changes in leaf-level characteristics. At ambient levels of CO2 , leaf net photosynthesis (A) of YD6 was compatible with that of W23. However, at elevated CO2 , A was higher for YD6 relative to W23. The stability of leaf Rubisco content, biochemical characteristics (Vc,max, and Jmax ), nitrogen enzymatic activity, and chlorophyll concentration differed significantly, with greater values observed for YD6 relative to W23 at elevated CO2 . While such results are consistent with other studies, we also demonstrate that a higher ratio of carbon sinks (seed) to carbon sources (leaf), were linked to increases in cytokinins, and slower flag leaf senescence for the YD6 relative to the W23 cultivar at elevated CO2 . While additional data for a broader genetic selection are needed, the current study suggests a link between source/sink carbon assimilation, maintenance of photosynthetic biochemistry, and slower leaf senescence for rice cultivars that show a stronger yield response to projected CO2 levels. This information, in turn, may provide suitable metrics for future CO2 selection among rice cultivars.

The Toxic Mechanism of Gliotoxins and Biosynthetic Strategies for Toxicity Prevention.

Gliotoxin is a kind of epipolythiodioxopiperazine derived from different fungi that is characterized by a disulfide bridge. Gliotoxins can be biosynthesized by a gli gene cluster and regulated by a positive GliZ regulator. Gliotoxins show cytotoxic effects via the suppression the function of macrophage immune function, inflammation, antiangiogenesis, DNA damage by ROS production, peroxide damage by the inhibition of various enzymes, and apoptosis through different signal pathways. In the other hand, gliotoxins can also be beneficial with different doses. Low doses of gliotoxin can be used as an antioxidant, in the diagnosis and treatment of HIV, and as an anti-tumor agent in the future. Gliotoxins have also been used in the control of plant pathogens, including Pythium ultimum and Sclerotinia sclerotiorum. Thus, it is important to elucidate the toxic mechanism of gliotoxins. The toxic mechanism of gliotoxins and biosynthetic strategies to reduce the toxicity of gliotoxins and their producing strains are summarized in this review.

State preparation robust to modulation signal degradation by use of a dual parallel modulator for high-speed BB84 quantum key distribution systems.

Security certification of quantum key distribution systems with a practical device is essential for their social deployment. Considering the transmitter, we investigate quantum state generation affected by degraded electrical signals from practical bandwidth-limited devices on high-speed phase-encoding BB84 quantum key distribution systems. The state preparation flaw caused by this degradation undesirably enhances the distinguishability between the two bases for the BB84 protocol and decreases the key generation rate. We propose the state preparation with a dual parallel modulator for increasing the robustness to signal degradation. To verify the effectiveness of the dual parallel modulator, we characterize the generated states using state tomography and estimate the key generation rate based on the Gottesman-Lo-Lütkenhaus-Preskill theory with fidelity derived from the estimated density matrices. Simulation results show that the key generation rate remains unaffected by modulation voltage shifts up to 20%.

4-Hydroxy Pyridones from Heterologous Expression and Cultivation of the Native Host.

4-Hydroxy pyridones are a class of fungi-derived polyketide-nonribosomal peptide products featuring a core of 4-hydroxy-2-pyridone which have a wide range of biological activities. Genome mining of in-house strains using polyketide synthase-nonribosomal peptide synthase as a query identified an endophyte Tolypocladium sp. 49Y, which possesses a potential 4-hydroxy pyridone biosynthetic gene cluster. Heterologous expression in Aspergillus oryzae NSAR1 revealed that this gene cluster is functional and able to produce a rare type of 4-hydroxy pyridones called tolypyridones (compounds 3 and 4). Tolypocladium sp. 49Y was grown in a variety of media which led to the isolation of six 4-hydroxy pyridones (5-10) and one pyrrolidone (11) from a rice culture, and compounds 3 and 9 showed antifungal activity. These latter compounds are different from those obtained by heterologous expression. This study shows that both heterologous expression and cultivation of the native host are complementary approaches to discover new natural products.

Activator protein-1 and caspase 8 mediate p38α MAPK-dependent cardiomyocyte apoptosis induced by palmitic acid.

Lipoapoptosis of cardiomyocytes may underlie diabetic cardiomyopathy. Numerous forms of cardiomyopathies share a common end-pathway in which apoptotic loss of cardiomyocytes is mediated by p38α mitogen activated protein kinase (MAPK). Although we have previously shown that palmitic acid (PA), a saturated fatty acid (SFA) elevated in plasma of type 2 diabetes mellitus and morbid obesity, induces apoptosis in cardiomyocytes via p38α MAPK-dependent signaling, the downstream cascade events that cause cell death remain unknown. The objective of this study was to investigate mechanisms involved in palmitic acid-induced cardiomyocyte apoptosis. Human adult ventricular cardiomyocyte line (AC16 cells) exposed to high physiological levels of PA for 16 h showed enhanced transcription and phosphorylation of c-fos and c-jun subunits of AP-1 and transcription of caspase 8. When AC16 cells were transfected with small interfering RNA specific against p38α MAPK (si-p38α) for 24 or 48 h, the amplified phosphorylation of c-fos was dose-dependently attenuated, and procaspase 8 was dose-dependently reduced. With translational knockdown of c-fos, PA-induced apoptosis was diminished. Inhibition of caspase 8 for 24 h reduced apoptosis in PA-treated cardiomyocytes. These findings provide evidence for induction of apoptosis in cardiomyocytes exposed to high SFA by a novel pathway requiring activation of c-fos/AP-1 and caspase 8. These results demonstrate how elevated plasma SFA may lead to continual and cumulative loss of cardiomyocytes and potentially contribute to the development of diabetic cardiomyopathy.

Role of brassinosteroids in rice spikelet differentiation and degeneration under soil-drying during panicle development.

BACKGROUND: Brassinosteroids (BRs) are a new group of plant hormones and play important roles in plant growth and development. However, little information is available if BRs could regulate spikelet development in rice (Oryza sativa L.) especially under soil-drying conditions. This study investigated whether and how BRs mediate the effect of soil-drying on spikelet differentiation and degeneration in rice. A rice cultivar was field-grown and exposed to three soil moisture treatments during panicle development, that is, well-watered (WW), moderate soil-drying (MD) and severe soil-drying (SD). RESULTS: Compared with the WW treatment, the MD treatment enhanced BRs biosynthesis in young panicles, increased spikelet differentiation and reduced spikelet degeneration. The SD treatment had the opposite effects. Changes in expression levels of key rice inflorescence development genes (OsAPO2 and OsTAW1), ascorbic acid (AsA) content, and activities of enzymes involved AsA synthesis and recycle, and amount of nonstructural carbohydrates (NSC) in young panicles were consistent with those in BRs levels, whereas hydrogen peroxide (H2O2) content showed opposite trend. Knockdown of the BRs synthesis gene OsD11 or application of a BRs biosynthesis inhibitor to young panicles markedly decreased OsAPO2 and OsTAW1 expression levels, BRs and AsA contents, activities of enzymes involved AsA synthesis and recycle, NSC amount in rice panicles and spikelet differentiation but increased the H2O2 content and spikelet degeneration compared to the control (the wide type or application of water). The opposite effects were observed when exogenous BRs were applied. CONCLUSIONS: The results suggest that BRs mediate the effect of soil-drying on spikelet differentiation and degeneration, and elevated BRs levels in rice panicles promote spikelet development under MD by enhancing inflorescence meristem activity, AsA recycle and NSC partitioning to the growing panicles.

New phenylpropanoid allopyranosides from the rhizomes of Cimicifuga dahurica.

Five new phenylpropanoid allopyranosides (1-5), along with five known compounds (6-10) were isolated from the rhizomes of Cimicifuga dahurica. Their structures were established by means of spectroscopic analyses and chemical methods, as well as comparison with literatures. The anti-inflammatory activities of all isolates were evaluated. Compounds 6, 9 and 10 exhibited inhibitory effects on PGE2 production in LPS stimulated RAW 264.7 macrophages with IC50 values of 19.72, 6.33 and 39.90 µM, respectively.

Human Papillomavirus Status in Primary Lesions and Pelvic Lymph Nodes and Its Prognostic Value in Cervical Cancer Patients with Lymph Node Metastases.

BACKGROUND The aim of this study was to assess the presence of HPV DNA in cervical tissues and lymph nodes in patients who have uterine cervical neoplasms with lymphatic metastases and who underwent surgery for invasive cervical cancer and pelvic lymphadenectomy, to establish the utility of HPV type and viral load in predicting disease progression. MATERIAL AND METHODS We retrospectively assessed 88 patients with uterine cervical neoplasms with lymph node metastases. All 88 patients were in FIGO stage IA-IIB. A total of 316 paraffin-embedded archival tissues (88 cervical samples and 228 pelvic lymph node specimens) were acquired. All the samples were analyzed using real-time PCR to determine HPV DNA presence/type and to quantify viral load. RESULTS In total, 17 HPV genotypes were detected in the cervical lesions and pelvic lymph nodes of the patients. The most common HPV type in all samples was HPV16, followed by HPV18. The existence of HPV16 DNA and low HPV16 viral load in cervical lesions were also significantly associated with disease recurrence. Furthermore, lymphovascular space involvement was also correlated with worse disease outcome. CONCLUSIONS HPV16 DNA presence and low viral load in primary lesions can be used to predict disease recurrence. HPV DNA is a favorable prognostic indicator in patients with uterine cervical neoplasms who have lymphatic metastases.

Brassinosteroids function in spikelet differentiation and degeneration in rice.

Brassinosteroids (BRs) play crucial roles in many aspects of plant development. However, their function in spikelet differentiation and degeneration in rice (Oryza sativa L.) remains unclear. Here, we investigated the roles of these phytohormones in spikelet development in field-grown rice subjected to five different nitrogen (N) fertilization treatments during panicle differentiation. BR levels and expression of genes involved in BR biosynthesis and signal transduction were measured in spikelets. Pollen fertility and the number of differentiated spikelets were closely associated with 24-epicastasterone (24-epiCS) and 28-homobrassinolide (28-homoBL) levels in spikelets. Enhanced BR biosynthesis and signal transduction, in response to N treatment, enhanced spikelet differentiation, reduced spikelet degeneration, and increased grain yield. Increases in proton-pumping ATPase activity, ATP concentration, energy charge, and antioxidant system (AOS) levels were consistent with 24-epiCS and 28-homoBL concentrations. Exogenous application of 24-epiCS or 28-homoBL on young panicles induced a marked increase in endogenous 24-epiCS or 28-homoBL levels, energy charge, AOS levels, spikelet differentiation, and panicle weight. The opposite effects were observed following treatment with a BR biosynthesis inhibitor. Our findings indicate that, in rice, BRs mediate the effects of N fertilization on spikelet development and play a role in promoting spikelet development through increasing AOS levels and energy charge during panicle development.

New lignans attenuating cognitive deterioration of Aß transgenic flies discovered in Acorus tatarinowii.

Five new lignan racemates, (±)-tatarinoid D-H (1-5), and three known analogues (6-8) were isolated from the rhizomes of Acorus tatarinowii. Their structures were established by 1D, 2D-NMR, HR-MS, IR and optical spectral data. Among them, 1 and 6-8 can alleviate the cognitive deterioration of Aß transgenic flies.

Self-assembling Ni(OH)2/α-Fe2O3 composites for pseudocapacitors with excellent electrochemical performance.

Novel two-dimensional (2D) nanostructured Ni(OH)2 nanosheet/α-Fe2O3 nanoplate composites (NFCs) were successfully synthesized by a simple two-step solvothermal method where the proportion of α-Fe2O3 nanoplates was found to be controllable. These composites achieved excellent performance in aqueous electrolyte due to the synergistic effect between Ni(OH)2 nanosheets and α-Fe2O3 nanoplates, such as high specific capacitance and long-term cycle stability. The obtained NFC8 possessed a maximum mass specific capacitance of 1745.33F g-1 at a current density of 2 A g-1, and with 84.28% retention after 3000 cycles galvanostatic charge/discharge at a high current density of 20 A g-1. The above results show that these novel 2D nanostructured Ni(OH)2/α-Fe2O3 composites are promising electrode materials for pseudocapacitors.

Two new compounds from a marine-derived Penicillium griseofulvum T21-03.

A new phenolic acid compound, 46-dimethylcurvulinic acid (1) and a new citrinin monomer derivative penicitrinol P (2) were isolated from marine-derived Penicillium griseofulvum T21-03. The structures of 1 and 2 were elucidated on the basis of spectroscopic data.

Freestanding polyaniline nanorods grown on graphene for highly capacitive energy storage.

Freestanding polyaniline (PANI) nanorods grown in situ on microwave-expanded graphene oxide (MEGO) sheets were prepared through a facile solution method. The morphological characterization indicates that large quantity of free-standing PANI nanorods with average diameter of 50 nm were uniformly deposited onto the double sides of the MEGO nanosheets to form a sandwich structure. The hybrid of PANI/MEGO (GPANI) exhibit high specific surface area and high electrical conductivity, compared with pristine PANI nanorods. When evaluated as electrodes for supercapacitors, the GPANI demonstrate high specific capacitance of 628 F g(-1) at a current density of 1.1 A g(-1), high-rate performance, and excellent cycle stability compared to individual component. Such excellent electrochemical performance should be attributed to the combined double-layer capacitance and pseudo -capacitance mechanisms from the MEGO sheets and PANI nanorods.