Soluble Protein Research Articles

Biosynthesis of copper nanoparticles using Solenostemma argel and their effect on enhancing salt tolerance in barley plants

The distinctive characteristics of nanoparticles and their potential applications have been given considerable attention by scientists across different fields, particularly agriculture. However, there has been limited effort to assess the impact of copper nanoparticles (CuNPs) in modulating physiological and biochemical processes in response to salt-induced stress. This study aimed to synthesize CuNPs biologically using Solenostemma argel extract and determine their effects on morphophysiological parameters and antioxidant defense system of barley (Hordeum vulgare) under salt stress. The biosynthesized CuNPs were characterized by (UV–vis spectroscopy with Surface Plasmon Resonance at 320 nm, the crystalline nature of the formed NPs was verified via XRD, the FTIR recorded the presence of the functional groups, while TEM was confirmed the shape (spherical) and the sizes (9 to 18 nm) of biosynthesized CuNPs. Seeds of barley plants were grown in plastic pots and exposed to different levels of salt (0, 100 and 200 mM NaCl). Our findings revealed that the supplementation of CuNPs (0, 25 and 50 mg/L) to salinized barley significantly mitigate the negative impacts of salt stress and enhanced the plant growth-related parameters. High salinity level enhanced the oxidative damage by raising the concentrations of osmolytes (soluble protein, soluble sugar, and proline), malondialdehyde (MDA) and hydrogen peroxide (H2O2). In addition, increasing the activities of enzymatic antioxidants, total phenol, and flavonoids. Interestingly, exposing CuNPs on salt-stressed plants enhanced the plant-growth characteristics, photosynthetic pigments, and gas exchange parameters. Furthermore, CuNPs counteracted oxidative damage by lowering the accumulation of osmolytes, H2O2, MDA, total phenol, and flavonoids, while simultaneously enhancing the activities of antioxidant enzymes. In conclusion, the application of biosynthesized CuNPs presents a promising approach and sustainable strategy to enhance plant resistance to salinity stress, surpassing conventional methods in terms of environmental balance.

Paraphoma chrysanthemicola Affects the Carbohydrate and Lobetyolin Metabolism Regulated by Salicylic Acid in the Soilless Cultivation of Codonopsis pilosula.

Paraphoma chrysanthemicola, an endophytic fungus isolated from the roots of Codonopsis pilosula, influences salicylic acid (SA) levels. The interaction mechanism between SA and P. chrysanthemicola within C. pilosula remains elusive. To elucidate this, an experiment was conducted with four treatments: sterile water (CK), P. chrysanthemicola (FG), SA, and a combination of P. chrysanthemicola with salicylic acid (FG+SA). Results indicated that P. chrysanthemicola enhanced plant growth and counteracted the growth inhibition caused by exogenous SA. Physiological analysis showed that P. chrysanthemicola reduced carbohydrate content and enzymatic activity in C. pilosula without affecting total chlorophyll concentration and attenuated the increase in these parameters induced by exogenous SA. Secondary metabolite profiling showed a decrease in soluble proteins and lobetyolin levels in the FG group, whereas SA treatment led to an increase. Both P. chrysanthemicola and SA treatments decreased antioxidase-like activity. Notably, the FG group exhibited higher nitric oxide (NO) levels, and the SA group exhibited higher hydrogen peroxide (H2O2) levels in the stems. This study elucidated the intricate context of the symbiotic dynamics between the plant species P. chrysanthemicola and C. pilosula, where an antagonistic interaction involving salicylic acid was prominently observed. This antagonism was observed in the equilibrium between carbohydrate metabolism and secondary metabolism. This equilibrium had the potential to engage reactive oxygen species (ROS) and nitric oxide (NO).

Inhibition of autophagy prevents cardiac dysfunction at early stages of cardiomyopathy in Bag3-deficient hearts

The HSP70 co-chaperone BAG3 targets unfolded proteins to degradation via chaperone assisted selective autophagy (CASA), thereby playing pivotal roles in the proteostasis of adult cardiomyocytes (CMs). However, the complex functions of BAG3 for regulating autophagy in cardiac disease are not completely understood. Here, we demonstrate that conditional inactivation of Bag3 in murine CMs leads to age-dependent dysregulation of autophagy, associated with progressive cardiomyopathy. Surprisingly, Bag3-deficient CMs show increased canonical and non-canonical autophagic flux in the juvenile period when first signs of cardiac dysfunction appear, but reduced autophagy during later stages of the disease. Juvenile Bag3-deficient CMs are characterized by decreased levels of soluble proteins involved in synchronous contraction of the heart, including the gap junction protein Connexin 43 (CX43). Reiterative administration of chloroquine (CQ), an inhibitor of canonical and non-canonical autophagy, but not inactivation of Atg5, restores normal concentrations of soluble cardiac proteins in juvenile Bag3-deficient CMs without an increase of detergent-insoluble proteins, leading to complete recovery of early-stage cardiac dysfunction in Bag3-deficient mice. We conclude that loss of Bag3 in CMs leads to age-dependent differences in autophagy and cardiac dysfunction. Increased non-canonical autophagic flux in the juvenile period removes soluble proteins involved in cardiac contraction, leading to early-stage cardiomyopathy, which is prevented by reiterative CQ treatment.

Replacing traditional nursery soil with spent mushroom substrate improves rice seedling quality and soil substrate properties.

Currently, large quantities of spent mushroom substrate (SMS) are produced annually. Because SMS has high water retention and nutrients, it has great potential to replace traditional topsoil for raising seedlings in agricultural production. However, few studies have examined the effects of substituting SMS for paddy soil on rice seedling growth and soil nutrients. SMS was mixed with rice soil in different proportions (20%, 50%, and 80%), and chemical fertilizer, organic fertilizer, and peat substrate were added in addition to equivalent nitrogen as a traditional seedling nursery method for comparison. Compared to traditional paddy soil (CK), the seedling qualities of the three SMS ratio treatments were all higher. Adding SMS at different ratios promoted rice seedling root growth, elevated the soluble protein concentration, and amplified the superoxide dismutase (SOD) enzymatic action in rice seedlings. Total porosity and aeration porosity of the soil increased by 17.40% and 32.90%, respectively. Soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) increased by 21.26-118.48%, 50.44-71.68%, and 23.08-80.17%, respectively. Besides, the relative abundance of Bacillus, Bacteroidetes, and other bacteria as well as the abundance of Ascomycota were all significantly increased. Adding 50% SMS increased the abundance of Pseudomonas by 8.42 times. The seedling quality of the 50% SMS treatment was even higher than chemical fertilizer and organic fertilizer treatments, only second to the peat substrate treatment. In summary, partial substitution of paddy soil with SMS can ameliorate substrate properties, improve seedling quality, and increase microbial diversity, indicating the suitability of SMS as a replacement for rice soil in seedling substrates. The 50% SMS ratio is the best. This study provides a basis for SMS to replace traditional rice soil in seedling cultivation.

Effects of Salt Water on Growth and Quality of Raphanus sativus L. and Physiological Responses against Salt Stress

To determine the optimal salinity of irrigation water for fruit radish cultivated in peat, five levels of salinized water were used to evaluate their effect on the growth and quality of fruit radish (Raphanus sativus L.). Results showed that with an increase in salinity, the leaf growth was somehow inhibited, but the fleshy root growth increased, and quality improved with more soluble solids, sugar, protein, and Vitamin C substances in fleshy roots. With an increase in water salinity up to 4.2 dS/m, the weight of fleshy roots increased by 51.10% with a high increment in the root/shoot ratio. With the same salt concentration, the content of soluble solids in both root peal and pulp was the highest and improved by 11.06% and 6.70%, respectively. The soluble sugar content was the highest in root peals with the 4.2 dS/m treatment and in fleshy roots with the 7.4 dS/m treatment, with a 55.85% and 32.30% increase, respectively. The content of both soluble protein and vitamin C with the 4.2 dS/m treatment increased by 11.99% and 113.36%, respectively. Strong evidence derived from the study has indicated that 4.2 dS/m salinized irrigation water is optimal for growing ‘ice-cream’ fruit radishes and maintaining ultimate root weight and quality.

Re-watering solution facilitates seed germination and seedling growth of Carex schmidtii: Implication for species re-introduction in degraded semi-arid wetlands

Water deficiency threatens the health and function of wetlands in semi-arid areas. Optimum re-watering is an effective method for close-to-natural restoration to mitigate wetland degradation. Although the ecological importance of optimal re-watering as a nature-based solution for promoting wetland plant growth has been widely recognized, the response mechanisms of seed germination and seedling growth to re-watering are still poorly understood despite their decisive impact on plant life history. To fill this gap, this study compared the characteristics of seed germination and seedling growth in Carex schmidtii under initial water content with three levels (30%, 50%, and 70%) and five re-watering treatments (maintained at constant water content and re-watering to 100% on 7th, 14th, 21st, and 28th day). Moreover, the degree of reserve mobilization during four germination stages (seed suckering, sprouting, 20% germination, and seedling growth) was investigated. The results showed that water deficiency and re-watering treatments significantly affected C. schmidtii seed germination, seedling growth, and reserve mobilization. Compared with the other treatments, 50% moisture content and re-watering to 100% on the 14th day (50%-RT3) treatment significantly improved germination traits (germination rate, daily germination rate, germination index, and vigor index) and seedling growth characteristics (shoot length, root length, shoot biomass, root biomass, and total biomass). Furthermore, the degree of mobilization of starch, soluble protein, fat, and soluble sugar accumulation in C. schmidtii seeds under 50%-RT3 was higher than that in the other treatments. The structural equation model showed that the characteristics of seed germination and seedling growth of C. schmidtii were directly related to water deficiency and re-watering treatments, whereas reserve mobilization indirectly affected seed germination and seedling growth. These findings demonstrated that water deficiency and re-watering treatments have a crucial regulatory effect on seed germination and seedling growth of wetland plant species through a dual mechanism. This study provides information for the formulation of an optimum re-watering strategy for wetland vegetation restoration in semi-arid areas of the world.

GATSol, an enhanced predictor of protein solubility through the synergy of 3D structure graph and large language modeling

BackgroundProtein solubility is a critically important physicochemical property closely related to protein expression. For example, it is one of the main factors to be considered in the design and production of antibody drugs and a prerequisite for realizing various protein functions. Although several solubility prediction models have emerged in recent years, many of these models are limited to capturing information embedded in one-dimensional amino acid sequences, resulting in unsatisfactory predictive performance.ResultsIn this study, we introduce a novel Graph Attention network-based protein Solubility model, GATSol, which represents the 3D structure of proteins as a protein graph. In addition to the node features of amino acids extracted by the state-of-the-art protein large language model, GATSol utilizes amino acid distance maps generated using the latest AlphaFold technology. Rigorous testing on independent eSOL and the Saccharomyces cerevisiae test datasets has shown that GATSol outperforms most recently introduced models, especially with respect to the coefficient of determination R2, which reaches 0.517 and 0.424, respectively. It outperforms the current state-of-the-art GraphSol by 18.4% on the S. cerevisiae_test set.ConclusionsGATSol captures 3D dimensional features of proteins by building protein graphs, which significantly improves the accuracy of protein solubility prediction. Recent advances in protein structure modeling allow our method to incorporate spatial structure features extracted from predicted structures into the model by relying only on the input of protein sequences, which simplifies the entire graph neural network prediction process, making it more user-friendly and efficient. As a result, GATSol may help prioritize highly soluble proteins, ultimately reducing the cost and effort of experimental work. The source code and data of the GATSol model are freely available at https://github.com/binbinbinv/GATSol.

Effect of alkaline treatment duration on rapeseed protein during pH-shift process: Unveiling physicochemical properties and enhanced emulsifying performance

Effect of alkaline treatment duration on rapeseed protein during pH-shift process: Unveiling physicochemical properties and enhanced emulsifying performance

Development and application of a colloidal-gold immunochromatographic strip for detecting Getah virus antibodies

Getah virus (GETV) is a re-emerging mosquito-borne alphavirus that is highly pathogenic, mainly to pigs and horses. There are no vaccines or treatments available for GETV in swine in China. Therefore, the development of a simple, rapid, specific, and sensitive serological assay for GETV antibodies is essential for the prevention and control of GETV. Current antibody monitoring methods are time-consuming, expensive, and dependent on specialized instrumentation, and these features are not conducive to rapid detection in clinical samples. To address these problem, we developed immunochromatographic test strips (ICTS) using eukaryotically expressed soluble recombinant p62-E1 protein of GETV as a labelled antigen, which has good detection sensitivity and no cross-reactivity with other common porcine virus-positive sera. The ICTS is highly compatible with IFA and ELISA and can be stored for 1 month at 37 °C and for at least 3 months at room temperature. Hence, p62-E1-based ICTS is a rapid, accurate, and convenient method for rapid on-site detection of GETV antibodies.Key points• We established a rapid antibody detection method that can monitor GETV infection• We developed colloidal gold test strips with high sensitivity and specificity• The development of colloidal gold test strips will aid in the field serologic detection of GETV

AIPAC-003: A randomized, double-blind, placebo-controlled phase 3 trial testing eftilagimod alpha (soluble LAG-3) in patients with HER2-neg/low metastatic breast cancer receiving paclitaxel, following an open-label dose optimization.

TPS1125 Background: Eftilagimod alpha (efti), a soluble LAG-3 protein, acts as an MHC class II agonist that enhances immunity by mediating antigen presenting cell and CD8 T-cell activation. Data from a randomized, phase 2b trial of efti plus paclitaxel compared to placebo plus paclitaxel in patients (pts) with HR+ HER2– metastatic breast cancer (MBC) (AIPAC; NCT02614833) showed sustained pharmacodynamic activity that was linked to improved overall survival (OS) in the efti arm. AIPAC-003 is a randomized, double-blind, placebo-controlled phase 3 trial testing efti plus paclitaxel in HER2-neg/low MBC pts, following an initial open-label dose optimization lead-in (DOL) component to determine the optimal biological dose (OBD) of efti in this combination. Methods: The DOL phase will determine the OBD of efti prior to start of the P3 part of the study. Enrolment for the DOL began in November 2023 with the aim to recruit 66 pts. Primary objectives in the DOL are: safety and tolerability of 90 mg vs 30 mg efti and defining the OBD of efti in combination with weekly paclitaxel. Determination of the OBD will be based on the totality of safety and tolerability data together with overall response rate (ORR) and pharmacodynamic marker (CD8+ T cells, absolute lymphocyte count) data. Secondary objectives in the DOL include efficacy, QoL and PK profile always of 30 mg efti vs. 90 mg on top of weekly paclitaxel. In the Phase 3 component pts will be randomized to receive either paclitaxel + efti or paclitaxel + placebo in a double-blinded fashion. The primary endpoint (EP) for the proposed Phase 3 is OS and the exact patient population will be defined after determination of the OBD. Key secondary EPs include progression free survival and ORR by RECIST 1.1, quality of life and safety. Pts will receive paclitaxel (80 mg/m2 I.V. on D1, 8 and 15 in a 4-week cycle), followed by efti or placebo (DOL: 30 or 90 mg efti; Phase 3: OBD of efti or placebo) S.C. on D1 and 15 in a 4-week cycle for up to 12 months. Imaging is done every 8 weeks and assessed by the investigator. in the DOL blood samples are taken from 0 to 96 hours in cycle 1 and 4 to determine PK / PD profiles. PK / PD parameters are assessed by a central lab. Key inclusion criteria: Pts with either a) HR+ and HER2-neg/low and endocrine therapy-resistant MBC or b) TNBC not eligible for anti-PD-1-based therapy. Pts must have measurable disease, ECOG PS 0-1 and no prior chemotherapy for metastatic disease. Key exclusion criteria: Pts if HR+ who are not considered endocrine resistant and/or have received < 1 line of therapy in the metastatic setting. Pts who are considered TNBC and are eligible for anti-PD-(L)1 containing therapy. Clinical trial information: NCT05747794 .

A time-saving pH-ultrasonic-shifting method for insoluble pea protein isolate to encapsulate polyphenol: Binding mechanism, structure, and functional characteristics

The application of the commercial pea protein isolate (CPPI) and polyphenols are often limited by their poor solubility. To address it, a time-saving pH-ultrasonic-shifting method was skillfully developed by combining the pH-shifting and ultrasonic methods to efficiently encapsulate polyphenols, and this final obtained nanoparticles was named CPPI-NAR-4. CPPI-NAR-4 has shown higher encapsulation efficiency (EE, 93.81 ± 0.56%) and loading capacity (LC, 8.58 ± 0.05%) for NAR, smaller particle size (126.40 ± 3.84 nm) and lower zeta potential (−18.50 ± 0.98 mV) as compared to nanoparticles prepared by other three known methods. This high EE and LC of CPPI-NAR-4 were attributed by both CPPI-NAR-4 and CPPI-4 having the higher surface hydrophobicity, the higher fluorescence intensity, and more protein expansion in their comparison. Multi-spectra evaluations indicated that the pH-ultrasonic-shifting process might produce more hydrogen bonding in the combination of CPPI and NAR. As to the interaction mechanisms between CPPI and NAR in CPPI-NAR nanoparticles, molecular docking results showed that hydrogen bonds, van der Waals forces, and hydrophobic interactions were dominant in the binding of NAR and CPPI; further molecular dynamics simulations revealed that NAR and CPPI had more interactions at pH 12 than at pH 7. Based on these experimental and simulative results, it could be suggested that the effects of ultrasonic on the binding between CPPI and NAR might be better at pH 12 than at pH 7. In conclusion, this pH-ultrasonic-shifting method was expected to be further developed for industrial fabricating protein-polyphenol nanoparticles such as CPPI-NAR.

Enhancement of biochemical parameters and enzyme activity in solid-state fermented and biofortified maize cobs utilizing yeasts and plant extracts

This study investigated the impact of solid-state fermentation and biofortification of maize cobs using yeast and plant extracts on their biochemical properties and enzyme activity. Maize cobs were fermented with extracts from elephant grass, cassava leaves, or Siam weed, combined with baker's yeast or palm wine yeast. In vitro assays revealed increased l-lysine concentration (up to 8.6 mg/g), soluble protein content (up to 27.4 mg/g), total phenolic content (up to 15.5 μg GAE/g), total flavonoid content (up to 23.4 μg CE/g), and xylanase activity (up to 25.7 Units) compared to controls. Glucose concentration decreased (to 0.8 mg/mL), indicating efficient utilization. Amylase and protease activities varied, with some combinations showing higher enzymatic activity (amylase at 35.4 Units, protease at 39.2 Units). These results underscore the potential of solid-state fermentation and biofortification to enhance the nutritional quality of agro-residues, offering novel insights into sustainable food production and waste utilization strategies.

Unraveling the contribution of copper seed priming in enhancing chromium tolerance in wheat by improving germination, growth, and grain yield.

Exposure to chromium (Cr) on farmlands drastically restricts the growth and productivity of cereal crops, including wheat (Triticum aestivum L.). Utilizing micronutrients, the seed-priming strategy is crucial to preventing the adverse consequences of Cr-stress. Nevertheless, additional investigation needs to be conducted to figure out whether Cu-priming remedies are beneficial for wheat experiencing Cr-stress. The objective of this study was to ascertain the contribution of Cu-treated seed priming in the mitigation of detrimental impacts of Cr-stress on wheat germination, growth, and production. Two wheat cultivars, Dilkash-20 and Subhani-21, were subjected to seed priming treatments (0mg/L, 0.1mg/L, and 1.0mg/L) of Cu under Cr-stress levels (200mg/kg) in two successive experiments, respectively, petri-dish and soil-filled pot experiments. The Cu-priming significantly enhanced the wheat seed germination, plant growth, and grain yield under Cr-stress. Cu priming improved enzyme activities such as glutathione peroxidase (14.60, 16.30%), superoxide dismutase (62.55, 115.21%), peroxidase, catalase (78.39, 80.23%), ascorbate peroxidase(17.72, 20.32%), and key primary and secondary metabolites such as proline (54.19, 81.27%), glycine betaine (40.13, 79.39%), total soluble proteins (47.92, 51.58%), phenolics (40.05, 18.61%), and flavonoids (56.90, 113.46%), respectively, of Dilkash-20 and Subhani-21 under Cr-stress. The outcome of our investigation underscored the efficacy of Cu-priming treatments (0.1mg/L and 1.0mg/L) in Cr-stress circumstances to augment wheat germination, growth, and grain yield.

Effects of different rootstocks grafting on selenium accumulation in Cyphomandra betacea Sendt. seedlings under selenium-contaminated soil

The effects of rootstocks tomato (Solanum lycopersicum L.), eggplant (Solanum melongena L.), and nightshade (Solanum nigrum L.) grafting on the growth and selenium (Se) accumulation of Cyphomandra betacea Sendt. seedlings were studied to identify the most suitable rootstock for increasing Se uptake of fruit trees grown in Se-contaminated soil. The rootstocks of tomato, eggplant, and nightshade grafting increased the scion biomass of C. betacea seedlings by 146.1%, 23.2%, and 94.5%, respectively, compared with the un-grafted seedlings. Moreover, tomato, eggplant, and nightshade rootstocks grafting increased the photosynthesis, superoxide dismutase activity, and peroxidase activity, while reducing the catalase activity and soluble protein content of C. betacea seedlings. Although all three rootstocks grafting decreased Se contents in rootstock roots and stems, only nightshade rootstock grafting increased Se content in the scions of C. betacea seedlings. Notably, root biomass, catalase activity, soluble protein content, rootstock root Se content, and rootstock stem Se content were closely related to the scion Se content. These findings suggest that only grafting onto nightshade rootstock significantly enhances Se uptake in C. betacea, whereas tomato and eggplant rootstocks grafting have no effect on Se uptake.

A synergistic catalytic system of keratinases and disulfide reductases for the bioconversion of feather wastes to feed alternative protein

Effective hydrolysis of feather waste by keratinase is an important way to develop high-quality alternative proteins for feed. It has been shown that the reduction of disulfide bonds is the key rate-limiting step in the hydrolysis of feathers by keratinases. However, the reductive activity of keratinase itself is low. In order to increase the reductive activity of the catalytic system, we screened endogenous disulfide reductase from Bacillus subtilis and constructed a synergistic catalytic system, KerZ1/yjbI-S2-P1, consisting of keratinase and disulfide reductase by co-expression optimization. The reductive activity and feather hydrolytic activity of the synergistic system were 5.67-fold and 5-fold higher than the original system. Feathers were hydrolyzed to a higher extent compared with the original system. The total amino acid and soluble protein concentrations in the products increased by 99% and 59%, respectively. This study provides a more environmentally friendly and efficient reduction capability for keratinase to hydrolysis waste feathers, and also demonstrates a new way of alternative protein feedstock mining.

Total Soluble Protein Mediated Morphological Traits in Mustard Treated with Thiourea and Salicylic Acid

The total soluble protein-mediated morphological traits in mustard treated with Thiourea and Salicylic acid were investigated. In addition, it tested the hypothesis that the growth regulator salicylic acid protects the photosynthetic apparatus by up-regulating morphological traits. Under natural environmental conditions, seeds were sown in the field, and seed emergence was recorded. For three days after the 15-day stage, plants in the area were treated with thiourea and salicylic acid and allowed to grow for 90 days. Plants were harvested to assess various morphological traits. A follow-up application of SA and Thiourea plants improved plant height, leaf area, internodal length, leaf number, and accelerated plant activity. The up-regulation of morphological traits may have occurred in SA and Thiourea-mediated plants. After treatments, the level of total soluble protein was estimated in the leaves at proposed day intervals.

Optimizing glutamate production from microalgae extracts sourced from the Caspian Sea Basin: A cost-effective and sustainable approach with potential applications

The versatile free amino acid known as glutamate plays a key role in biological processes as a transmitter of signals between nerve cells, as well as in the food industry as a flavor enhancer. Extensive endeavors have been undertaken to produce glutamate using various methods, often relying on costly and scarce natural resources. This study aims to explore a cost-effective and abundant natural alternative for glutamate synthesis by utilizing microalgae extract sourced from the Caspian Sea basin. To achieve this goal, the submerged fermentation method was utilized. The fermented microalgae extract, inoculated with P. putida, exhibited substantially higher concentrations of glutamate compared to the uninoculated samples. Amongst the various seaweeds investigated, the aqueous Chlorella extract exhibited the highest Glutamate amount (3.1 ± 0.1 mg/g). Moreover, both the fresh and dehydrated microalgae extracts displayed a noteworthy rise in the concentration of soluble proteins during fermentation. It is worth mentioning that extracts treated with P. putida exhibited a total rise in the levels of overall phenolics and flavonoids, suggesting a promising improvement in their biologically active combinations. Furthermore, the functions of alpha-amylase and proteolytic enzymes experienced significant increments in the fermented extracts. This research highlights a promising method for generating glutamate using microalgae extract which has significant potential for the food industry, offering numerous advantages.

Insight into quality, microstructure, and protein physicochemical properties of Monopterus albus frozen with liquid nitrogen

Monopterus albus is highly susceptible to spoilage due to high protein and moisture contents while frozen storage can effectively prolong the shelf-life. To study the effect of liquid nitrogen freezing (LNF) on quality, microstructure of ice crystal and muscle fiber, and physicochemical properties of proteins, Monopterus albus was frozen at -20°C by refrigerator (RF, control), -50°C, -80°C, and -110°C by LNF, respectively. The -110°C LNF exhibited the highest freezing rate among four groups, contributing to the formation of small ice crystals with more uniform distribution and alleviating the damage to muscle fiber. In -110°C LNF group, protein secondary structure changed relatively subtle, resulting in high protein solubility, Ca2+-ATPase activity, and total sulfhydryl content, as well as low surface hydrophobicity and disulfide bond content. LNF retarded the rise of TVB-N value, prevented the loss of immobilized and free water, and maintained water holding capacity and shear force. In conclusion, -110°C LNF was recommended a promising freezing process for frozen Monopterus albus due to less alteration of quality and alleviation of protein denaturation.

Alteration of gene expression and protein solubility of the PI 5-phosphatase SHIP2 are correlated with Alzheimer’s disease pathology progression

A recent large genome-wide association study has identified EGFR (encoding the epidermal growth factor EGFR) as a new genetic risk factor for late-onset AD. SHIP2, encoded by INPPL1, is taking part in the signalling and interactome of several growth factor receptors, such as the EGFR. While INPPL1 has been identified as one of the most significant genes whose RNA expression correlates with cognitive decline, the potential alteration of SHIP2 expression and localization during the progression of AD remains largely unknown. Here we report that gene expression of both EGFR and INPPL1 was upregulated in AD brains. SHIP2 immunoreactivity was predominantly detected in plaque-associated astrocytes and dystrophic neurites and its increase was correlated with amyloid load in the brain of human AD and of 5xFAD transgenic mouse model of AD. While mRNA of INPPL1 was increased in AD, SHIP2 protein undergoes a significant solubility change being depleted from the soluble fraction of AD brain homogenates and co-enriched with EGFR in the insoluble fraction. Using FRET-based flow cytometry biosensor assay for tau-tau interaction, overexpression of SHIP2 significantly increased the FRET signal while siRNA-mediated downexpression of SHIP2 significantly decreased FRET signal. Genetic association analyses suggest that some variants in INPPL1 locus are associated with the level of CSF pTau. Our data support the hypothesis that SHIP2 is an intermediate key player of EGFR and AD pathology linking amyloid and tau pathologies in human AD.

The Physiological Mechanism of Low-Temperature Tolerance Following the UV-B Radiation of Eucommia ulmoides Oliver

Eucommia ulmoides Oliver with rich active components, such as flavonoids, lignans, polysaccharides, is used as a medicinal plant. Unfortunately, its popularization and cultivation are limited due to its low-temperature sensitivity. In this study, we aimed to explore the effect of different doses of ultraviolet-B (UV-B) radiation (UV-1, UV-2, and UV-3) and low-temperature (LT) stress, both applied individually and in combination, on the photosynthetic properties, biochemical parameters, and the contents of salicylic acid in E. ulmoides plants. The results showed that UV-B radiation alone significantly reduced photosynthetic performance and soluble total sugar content, as well as causing increases in soluble protein, proline, and superoxide anion content and antioxidant activity including SOD, POD, CAT, total phenol, and total flavonoid content. The leaf thickness and photosynthetic parameters significantly increased, as well as a significant decrease in SOD activity and soluble sugar, proline, and superoxide anion content after 14 days of none-UV-B radiation exposure. UV-B combined with LT significantly improved photosynthetic properties, Chl content, and soluble sugar content but significantly decreased proline content. Principal component analysis showed that salicylic acid was the key factor in improving LT tolerance, and UV-2 radiation showed the best LT resistance. We aim to provide new ideas and a theoretical basis for the directional cultivation and LT stress tolerance research of E. ulmoides. Our findings demonstrate that the combined effect was more positively helpful in improving the ability to resist LT tolerance via the improvement of photosynthetic ability and the increase in soluble sugar and salicylic acid content in E. ulmoides.