Manganese (Mn) is an essential element for plant growth due to its participation in a series of physiological and metabolic processes. Mn is also considered a heavy metal that causes phytotoxicity ...when present in excess, disrupting photosynthesis and enzyme activity in plants. Thus, Mn toxicity is a major constraint limiting plant growth and production, especially in acid soils. To cope with Mn toxicity, plants have evolved a wide range of adaptive strategies to improve their growth under this stress. Mn tolerance mechanisms include activation of the antioxidant system, regulation of Mn uptake and homeostasis, and compartmentalization of Mn into subcellular compartments (e.g., vacuoles, endoplasmic reticulum, Golgi apparatus, and cell walls). In this regard, numerous genes are involved in specific pathways controlling Mn detoxification. Here, we summarize the recent advances in the mechanisms of Mn toxicity tolerance in plants and highlight the roles of genes responsible for Mn uptake, translocation, and distribution, contributing to Mn detoxification. We hope this review will provide a comprehensive understanding of the adaptive strategies of plants to Mn toxicity through gene regulation, which will aid in breeding crop varieties with Mn tolerance via genetic improvement approaches, enhancing the yield and quality of crops.
Incredible accomplishments have been achieved in agricultural production in China, but many demanding challenges for ensuring food security and environmental sustainability remain. Field experiments ...were conducted from 2011-2013 at three different sites, including Honghu, Shayang, and Jingzhou in China, to determine the effects of fertilization on enhancing crop productivity and indigenous nutrient-supplying capacity (INuS) in a rice (Oryza sativa L.)-rapeseed (Brassica napus L.) rotation. Four mineral fertilizer treatments (NPK, NP, NK and PK) were applied in a randomized complete block design with three replicates. Crop yields were increased by 19-41% (rice) and 61-76% (rapeseed) during the two years of rice-rapeseed rotation under NPK fertilization compared to PK fertilization across the study sites. Yield responses to fertilization were ranked NPK > NP > NK > PK, illustrating that N deficiency was the most limiting condition in a rice-rapeseed rotation, followed by P and K deficiencies. The highest and lowest N, P and K accumulations were observed under NPK and PK fertilization, respectively. The INuS of the soil decreased to a significant extent and affected rice-rapeseed rotation productivity at each site under NP, NK, and PK fertilization when compared to NPK. Based on the study results, a balanced nutrient application using NPK fertilization is a key management strategy for enhancing rice-rapeseed productivity and environmental safety.
Gastric cancer is a common malignant tumor originating from the gastric mucosa epithelium. Studies have shown that bioactive substances such as antimicrobial peptides and cantharidin contained in a ...variety of insects can exert anti-cancer functions; when compared with chemotherapy drugs, these bioactive substances have less toxicity and reduced side effects. Here, we report the first
carboxypeptidase inhibitor that is specifically and highly expressed in silk glands, which can significantly prevent the proliferation of gastric cancer cells by inhibiting the MAPK/ERK pathway initiated by EGF/EGFR through the promotion of expression of the proto-oncogene c-Myc, thereby affecting the expression of related cyclins. Through molecular docking and virtual screening of silkworm carboxypeptidase inhibitors and epidermal growth factor receptors, we identified a polypeptide that overlapped with existing small-molecule inhibitors of the receptor. In the present work, we explore the medicinal potential and application of silkworm carboxypeptidase inhibitors to promote the development of anti-tumor drugs from insect-derived substances.
Although ignored in the past, with the recent deepening of research, significant progress has been made in the field of non-coding RNAs (ncRNAs). Accumulating evidence has revealed that microRNA ...(miRNA) response elements regulate RNA. Long ncRNAs, circular RNAs, pseudogenes, miRNAs, and messenger RNAs (mRNAs) form a competitive endogenous RNA (ceRNA) network that plays an essential role in cancer and cardiovascular, neurodegenerative, and autoimmune diseases. Gastric cancer (GC) is one of the most common cancers, with a high degree of malignancy. Considerable progress has been made in understanding the molecular mechanism and treatment of GC, but GC's mortality rate is still high. Studies have shown a complex ceRNA crosstalk mechanism in GC. lncRNAs, circRNAs, and pseudogenes can interact with miRNAs to affect mRNA transcription. The study of the involvement of ceRNA in GC could improve our understanding of GC and lead to the identification of potential effective therapeutic targets. The research strategy for ceRNA is mainly to screen the different miRNAs, lncRNAs, circRNAs, pseudogenes, and mRNAs in each sample through microarray or sequencing technology, predict the ceRNA regulatory network, and, finally, conduct functional research on ceRNA. In this review, we briefly discuss the proposal and development of the ceRNA hypothesis and the biological function and principle of ceRNAs in GC, and briefly introduce the role of ncRNAs in the GC's ceRNA network.
Macrophage infiltration contributes to the instability of atherosclerotic plaques. In the present study, we investigated whether selective inhibition of PI3K/Akt/mTOR signaling pathway can enhance ...the stability of atherosclerotic plaques by activation of macrophage autophagy. In vitro study, selective inhibitors or siRNA of PI3K/Akt/mTOR pathways were used to treat the rabbit's peritoneal primary macrophage cells. Inflammation related cytokines secreted by macrophages were measured. Ultrastructure changes of macrophages were examined by transmission electron microscope. mRNA or protein expression levels of autophagy related gene Beclin 1, protein 1 light chain 3 II dots (LC3-II) or Atg5-Atg12 conjugation were assayed by quantitative RT-PCR or Western blot. In vivo study, vulnerable plaque models were established in 40 New Zealand White rabbits and then drugs or siRNA were given for 8 weeks to inhibit the PI3K/Akt/mTOR signaling pathway. Intravascular ultrasound (IVUS) was performed to observe the plaque imaging. The ultrastructure of the abdominal aortic atherosclerosis lesions were analyzed with histopathology. RT-PCR or Western blot methods were used to measure the expression levels of corresponding autophagy related molecules. We found that macrophage autophagy was induced in the presence of Akt inhibitor, mTOR inhibitor and mTOR-siRNA in vitro study, while PI3K inhibitor had the opposite role. In vivo study, we found that macrophage autophagy increased significantly and the rabbits had lower plaque rupture incidence, lower plaque burden and decreased vulnerability index in the inhibitors or siRNA treated groups. We made a conclusion that selective inhibition of the Akt/mTOR signal pathway can reduce macrophages and stabilize the vulnerable atherosclerotic plaques by promoting macrophage autophagy.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
China's ionic rare earth ore is of great strategic value because of its abundant medium and heavy rare earth elements (REEs). However, its rare earth reserves have decreased significantly in recent ...years. It is imperative to improve the utilization rate of existing rare earth mineral resources. In this study, a low-grade ionic rare earth ore was taken as the object of research. The relationships between pH value, concentration, and flow velocity of ammonium sulfate and leaching rate of REEs were studied by the response surface method (RSM) based on the central composite design (CCD) principle. A quadratic polynomial mathematical model for studying the leaching rate was established, and the leaching conditions were optimized.
The results showed that the pH value, concentration, and flow velocity had significant influences on the leaching rate and that the interaction between the pH value and concentration and that between the pH value and flow velocity also had significant effects on it. The optimal leaching conditions obtained by RSM optimization were a pH value, concentration, and flow velocity of 4.80, 5%, and 0.73 mL/min, respectively. The leaching rate under the optimal conditions was 97.10%, with a relative error of 0.705% to predicted value of the model, which shows that the obtained model has good predictive performance and has a certain guiding significance for the production practice of the ionic rare earth ore. The research results provide a scientific and stable basis for the production of this type of low-grade ionic rare earth ore by in situ leaching and also help to improve the resource utilization ratio.
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•A significant and reliable mathematical model for the leaching rate of REEs was obtained.•The pH value, concentration, and flow velocity of (NH4)2SO4 have significant influences on the leaching rate of REEs.•The obtained response surface quadratic model has good prediction performance for the leaching rate of REEs.
Straw application can not only increase crop yields, improve soil structure and enrich soil fertility, but can also enhance water and nutrient retention. The aim of this study was to ascertain the ...relationships between straw decomposition and the release-adsorption processes of K(+). This study increases the understanding of the roles played by agricultural crop residues in the soil environment, informs more effective straw recycling and provides a method for reducing potassium loss. The influence of straw decomposition on the K(+) release rate in paddy soil under flooded condition was studied using incubation experiments, which indicated the decomposition process of rice straw could be divided into two main stages: (a) a rapid decomposition stage from 0 to 60 d and (b) a slow decomposition stage from 60 to 110 d. However, the characteristics of the straw potassium release were different from those of the overall straw decomposition, as 90% of total K was released by the third day of the study. The batches of the K sorption experiments showed that crop residues could adsorb K(+) from the ambient environment, which was subject to decomposition periods and extra K(+) concentration. In addition, a number of materials or binding sites were observed on straw residues using IR analysis, indicating possible coupling sites for K(+) ions. The aqueous solution experiments indicated that raw straw could absorb water at 3.88 g g(-1), and this rate rose to its maximum 15 d after incubation. All of the experiments demonstrated that crop residues could absorb large amount of aqueous solution to preserve K(+) indirectly during the initial decomposition period. These crop residues could also directly adsorb K(+) via physical and chemical adsorption in the later period, allowing part of this K(+) to be absorbed by plants for the next growing season.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•Established the Minimum data set (MDS) indicators for cultivated-layer soil quality (CLSQ) diagnosis.•The CLSQI was generally between the reasonable (III) and unreasonable (IV) levels of red soil ...sloping farmland in southern China .•Defined the thresholds of MDS indicators for reasonable cultivated-layer construction.•Subsoiling is recommended for the recovery and improvement of CLSQ, and compaction exert an adverse impact on it.
Tillage is known to potentially affect soil quality in various ways, and employing appropriate tillage measures is crucial to construct a reasonable cultivated layer (RCL), which could maximize the storage and coordination of water, gas and heat conditions in the cultivated layer of red soil sloping farmland. This study aims to 1) select the key indicators to establish a minimum data set (MDS), 2) evaluate the quality of cultivated-layer soil and define the indicator threshold for RCL construction, and 3) develop a credible cultivated-layer soil quality index (CLSQI) for the cultivated layer with different tillage measures, and screen suitable tillage measures to improving the soil productivity of red soil sloping farmland. Taking the red soil sloping farmland in China as the research focus, the MDS is established by principal component analysis (PCA) in conjunction with the norm value, Furthermore, the membership function models (S type, anti-s-type, Parabola-type) are used to normalize the indicator data and then assess the CLSQ based on the CLSQI approache, determine the indicator threshold by the CLSQ grade and membership function model, and analyse the cultivated-layer improvement effect by different tillage measures. The results indicated that the MDS and the thresholds of six indicators defined as the cultivated-layer thickness (CLT ≥ 20.39 cm), saturated hydraulic conductivity (SHC ≥ 6.24 mm/min), shear strength (SS ≥ 3.16 kg/cm2), clay content of 10.0–28.1%, organic matter (OM ≥ 15.23 g/kg) and available phosphorus (AP ≥ 58.48 mg/kg), were established in this research for the soil quality assessment of red soil sloping farmland. Tillage methods notably influenced these indicators and CLSQ, and the CLSQI was the highest for subsoiling (0.58) and lowest for soil compaction (0.37); however, mechanical compaction imposed a negative impact on the CLSQ under agricultural modernization, so subsoiling was the recommended measure for the production of soil conditions in this area. Our findings demonstrated that the sloping farmland resources in the research area should be reasonably utilized for the construction of an RCL, and effective subsoiling was suggested for good recovery of cultivated-layer soil capacity and function to increase the CLSQ. Smallholder farmers should therefore be aware of the potential for high soil quality in the future as a result of subsoiling and maintain the soil indicators at a suitable or even high level.
The fusion of the A* and the dynamic windowing algorithm is commonly used for the path planning of mobile robots in dynamic environments. However, the planned path has the problems of redundancy and ...low security. This paper proposes a path planning algorithm based on the safety distance matrix and adaptive weight adjustment strategy to address the above problems. Firstly, the safety distance matrix and new heuristic function are added to the traditional A* algorithm to improve the safety of global path. Secondly, the weight of the evaluation sub-function in the dynamic window algorithm is adjusted through an adaptive weight adjustment strategy to solve the problem of path redundancy. Then, the above two improved algorithms are fused to make the mobile robot have dynamic obstacle avoidance capability by constructing a new global path evaluation function. Finally, simulations are performed on grid maps, and the fusion algorithm is applied to the actual mobile robot path planning based on the ROS. Simulation and experimental results show that the fusion algorithm achieves optimization of path safety and length, enabling the robot to reach the end point safely with real-time dynamic obstacle avoidance capability.
Manganese (Mn), an essential element for plants, can be toxic when present in excess. Stylo (Stylosanthes) is a pioneer tropical legume with great potential for Mn tolerance, but its Mn tolerance ...mechanisms remain poorly understood.
In this study, variations in Mn tolerance were observed among nine stylo genotypes. Stylo genotype 'RY5' exhibited the highest Mn tolerance compared to the other tested genotypes, whereas 'TF2001' was a Mn-sensitive genotype. The mechanisms underlying the response of stylo to Mn toxicity were further investigated using these two genotypes with contrasting Mn tolerance. Results showed that stylo genotype RY5 exhibited Mn tolerance superior to that of genotype TF2001, showing lower reductions in leaf chlorophyll concentration, chlorophyll fluorescence parameters, photosynthetic indexes and plant dry weight under Mn toxicity. A label-free quantitative proteomic analysis was conducted to investigate the protein profiles in the leaves and roots of RY5 in response to Mn toxicity. A total of 356 differentially expressed proteins (DEPs) were identified, including 206 proteins from leaves and 150 proteins from roots, which consisted of 71 upregulated, 62 downregulated, 127 strongly induced and 96 completely suppressed proteins. These DEPs were mainly involved in defense response, photosynthesis, carbon fixation, metabolism, cell wall modulation and signaling. The qRT-PCR analysis verified that 10 out of 12 corresponding gene transcription patterns correlated with their encoding proteins after Mn exposure. Finally, a schematic was constructed to reveal insights into the molecular processes in the leaves and roots of stylo in response to Mn toxicity.
These findings suggest that stylo plants may cope with Mn toxicity by enhancing their defense response and phenylpropanoid pathways, adjusting photosynthesis and metabolic processes, and modulating protein synthesis and turnover. This study provides a platform for the future study of Mn tolerance mechanisms in stylo and may lead to a better understanding of the potential mechanisms underlying tropical legume adaptation to Mn toxicity.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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