Stereotactic body radiation therapy suppresses myeloid-derived suppressor cells by regulating miR-21/Sorbin and SH3 Domain-containing Protein 1 axis.

BACKGROUND: Stereotactic body radiation therapy (SBRT) is a targeted form of radiotherapy used to treat early-stage cancers. Despite its effectiveness, the impact of SBRT on myeloid-derived suppressor cells (MDSCs) is not well understood. In this study, we examined how SBRT affects the differentiation and survival of MDSCs, as well as delved into the molecular mechanisms involved. METHODS AND RESULTS: SBRT was utilized on bone marrow (BM)-derived MDSCs to investigate its impact on the differentiation and survival of MDSCs using flow cytometry. An animal model of lung cancer was created to assess the anti-cancer properties of SBRT and the role of miR-21 expression in MDSCs. The interplay of miR-21 and Sorbin and SH3 domain-containing protein 1 (SORBS1) in MDSC differentiation was explored through dual luciferase activity assay, RT-qPCR, and Western blot analysis. The findings suggest that SBRT led to an increase in miR-21 levels, inhibited MDSC differentiation, and triggered cell apoptosis in BM cells. Inhibition of miR-21 reversed the effects of SBRT on MDSC differentiation and apoptosis. Additionally, it was revealed that SORBS1 was a downstream target of miR-21 in BM cells, and the miR-21/SORBS1 axis played a role in regulating MDSC differentiation and apoptosis induced by SBRT. Modulating miR-21 levels in vivo impinged on the response to SBRT treatment and the quantity of MDSCs in a mouse model of lung cancer. CONCLUSION: Our data indicate that the upregulation of miR-21 induced by SBRT may contribute to the inhibition of MDSC expansion in a lung cancer model.

Effects of Plant Polysaccharides Combined with Boric Acid on Digestive Function, Immune Function, Harmful Gas and Heavy Metal Contents in Faeces of Fatteners.

The experiment aimed to investigate the effects of plant polysaccharides combined with boric acid on digestive function, immune function and harmful gas and heavy metal contents in the faeces of fatteners. For this study, 90 healthy crossbred fatteners were selected and randomly divided into five groups: the control group was fed with a basal diet (Con); experimental group I was fed with basal diet + 40 mg/kg boric acid (BA); experimental group II was fed with basal diet + 40 mg/kg boric acid + 400 mg/kg Astragalus polysaccharides (BA+APS); experimental group III was fed with basal diet + 40 mg/kg boric acid + 200 mg/kg Ganoderma lucidum polysaccharides (BA+GLP); and experimental group IV was fed with basal diet + 40 mg/kg boric acid + 500 mg/kg Echinacea polysaccharides (BA+EPS). Compared with Con, the average daily gain (ADG), the trypsin activities in the duodenum and jejunum, the IL-2 levels in the spleen, the T-AOC activities and GSH-Px contents in the lymph node of fattening were increased in the BA group (p < 0.05), but malondialdehyde content in the lymph and spleen, and the contents of NH3, H2S, Hg, Cu, Fe and Zn in the feces and urine were decreased (p < 0.05). Compared with the BA, the ADG, gain-to-feed ratio (G/F), the trypsin and maltase activities in the duodenum and jejunum were increased in the BA+APS (p < 0.05), and the T-SOD activities in the spleen and T-AOC activities in the lymph node were also increased (p < 0.05), but the H2S level was decreased in the feces and urine (p < 0.05). Compared with the BA, the ADG, G/F and the trypsin and maltase activities in the duodenum were increased in the BA+GLP and BA+EPS (p < 0.05), the activities of maltase and lipase in the duodenum of fatteners in the BA+GLP and the activities of trypsin, maltase and lipase in the BA+EPS were increased (p < 0.05). Gathering everything together, our findings reveal that the combined addition of boric acid and plant polysaccharides in the diet of fatteners synergistically improved their growth performance and immune status. That may be achieved by regulating the activity of intestinal digestive enzymes, improving the antioxidant function and then promoting the digestion and absorption of nutrients. Furthermore, the above results reduce the emission of harmful gases and heavy metals in feces and urine.

The RING-Type Domain-Containing Protein GNL44 Is Essential for Grain Size and Quality in Rice (Oryza sativa L.).

Grain size in rice (Oryza sativa L.) shapes yield and quality, but the underlying molecular mechanism is not fully understood. We functionally characterized GRAIN NUMBER AND LARGE GRAIN SIZE 44 (GNL44), encoding a RING-type protein that localizes to the cytoplasm. The gnl44 mutant has fewer but enlarged grains compared to the wild type. GNL44 is mainly expressed in panicles and developing grains. Grain chalkiness was higher in the gnl44 mutant than in the wild type, short-chain amylopectin content was lower, middle-chain amylopectin content was higher, and appearance quality was worse. The amylose content and gel consistency of gnl44 were lower, and protein content was higher compared to the wild type. Rapid Visco Analyzer results showed that the texture of cooked gnl44 rice changed, and that the taste value of gnl44 was lower, making the eating and cooking quality of gnl44 worse than that of the wild type. We used gnl44, qgl3, and gs3 monogenic and two-gene near-isogenic lines to study the effects of different combinations of genes affecting grain size on rice quality-related traits. Our results revealed additive effects for these three genes on grain quality. These findings enrich the genetic resources available for rice breeders.

PI3K/Akt signaling pathway mediates the effect of low-dose boron on barrier function, proliferation and apoptosis in rat intestinal epithelial cells.

Boron is an essential trace element with roles in growth, development, and physiological functions; however, its mechanism of action is still unclear. In this study, the regulatory roles of the PI3K/Akt signaling pathway on boron-induced changes in barrier function, proliferation, and apoptosis in rat intestinal epithelial cells were evaluated. Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein expression levels of PCNA were higher, while the proportions of cells in the G0/G1 and S phases, apoptosis rate, and caspase-3 mRNA and protein expression levels were lower in cells treated with 0.8 mmol/L boron than in control IEC-6 cells (P < 0.01 or P < 0.05). However, 40 mmol/L boron decreased ZO-1 and Occludin levels, the proportion of cells in the G2/M phase, cell proliferation rate, and mRNA and protein levels of PCNA and increased the apoptosis rate and caspase-3 mRNA expression (P < 0.01 or P < 0.05). After specifically blocking PI3K and Akt signals (using LY294002 and MK-2206 2HCL), 0.8 mmol/L boron had no effects on Occludin, PCNA level, apoptosis rates, and caspase-3 levels (P < 0.05); however, the proliferation rate and PCNA levels decreased significantly (P < 0.01 or P < 0.05). The addition of 40 mmol/L boron did not affect ZO-1 and Occludin levels and did not affect the apoptosis rate or PCNA and caspase-3 levels. These results suggested that the PI3K/Akt signaling pathway mediates the effects of low-dose boron on IEC-6 cells.

Integrated non-targeted metabolomics and network pharmacology to reveal the mechanisms of berberine in the long-term treatment of PTZ-induced epilepsy.

AIMS: The increasing resistance to anti-seizure medications (ASMs) and the ambiguous mechanisms of epilepsy highlight the pressing demand for the discovery of pioneering lead compounds. Berberine (BBR) has received significant attention in recent years within the field of chronic metabolic disorders. However, the reports on the treatment of epilepsy with BBR are not systematic and the mechanism remains unclear. MAIN METHODS: In this study, the seizure behaviors of mice were recorded following subcutaneous injection of pentetrazol (PTZ). Non-targeted metabolomics was used to analyze the serum metabolites based on ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS). Meanwhile, multivariate statistical methods were used for metabolite identification and pathway analysis. Furthermore, network pharmacology, molecular docking, and quantitative real-time PCR assay were used for the target identification. KEY FINDINGS: BBR had anti-seizure effects on PTZ-induced seizure mice after long-term treatment. Tryptophan metabolism and phenylalanine metabolism were involved in regulating the therapeutic effects of BBR. SIGNIFICANCE: This study reveals the potential mechanism of BBR for epilepsy treatment based on non-targeted metabolomics and network pharmacology, which provides evidence for uncovering the pathogenesis of epilepsy, suggesting that BBR is a potential lead compound for anti-epileptic treatment.

An integrated in vitro human iPSCs-derived neuron and in vivo animal approach for preclinical screening of anti-seizure compounds.

INTRODUCTION: One-third of people with epilepsy continue to experience seizures despite treatment with existing anti-seizure medications (ASMs). The failure of modern ASMs to substantially improve epilepsy prognosis has been partly attributed to overreliance on acute rodent models in preclinical drug development as they do not adequately recapitulate the mechanisms of human epilepsy, are labor-intensive and unsuitable for high-throughput screening (HTS). There is an urgent need to find human-relevant HTS models in preclinical drug development to identify novel anti-seizure compounds. OBJECTIVES: This paper developed high-throughput preclinical screening models to identify new ASMs. METHODS: 14 natural compounds (α-asarone, curcumin, vinpocetine, magnolol, ligustrazine, osthole, tanshinone IIA, piperine, gastrodin, quercetin, berberine, chrysin, schizandrin A and resveratrol) were assessed for their ability to suppress epileptiform activity as measured by multi-electrode arrays (MEA) in neural cultures derived from human induced pluripotent stem cells (iPSCs). In parallel, they were tested for anti-seizure effects in zebrafish and mouse models, which have been widely used in development of modern ASMs. The effects of the compounds in these models were compared. Two approved ASMs were used as positive controls. RESULTS: Epileptiform activity could be induced in iPSCs-derived neurons following treatment with 4-aminopyridine (4-AP) and inhibited by standard ASMs, carbamazepine, and phenytoin. Eight of the 14 natural compounds significantly inhibited the epileptiform activity in iPSCs-derived neurons. Among them, piperine, magnolol, α-asarone, and osthole showed significant anti-seizure effects both in zebrafish and mice. Comparative analysis showed that compounds ineffective in the iPSCs-derived neural model also showed no anti-seizure effects in the zebrafish or mouse models. CONCLUSION: Our findings support the use of iPSCs-derived human neurons for first-line high-throughput screening to identify compounds with anti-seizure properties and exclude ineffective compounds. Effective compounds may then be selected for animal evaluation before clinical testing. This integrated approach may improve the efficiency of developing novel ASMs.

Proteomic Analysis of Rat Duodenum Reveals the Modulatory Effect of Boron Supplementation on Immune Activity.

The proper supplementation of boron, an essential trace element, can enhance animal immune function. We utilized the method of TMT peptide labeling in conjunction with LC-MS/MS quantitative proteomics for the purpose of examining the effects of boric acid on a rat model and analyzing proteins from the duodenum. In total, 5594 proteins were obtained from the 0, 10, and 320 mg/L boron treatment groups. Two hundred eighty-four proteins that exhibit differential expression were detected. Among the comparison, groups of 0 vs. 10 mg/L, 0 vs. 320 mg/L, and 10 vs. 320 mg/L of boron, 110, 32, and 179 proteins, respectively, demonstrated differential expression. The results revealed that these differential expression proteins (DEPs) mainly clustered into two profiles. GO annotations suggested that most of the DEPs played a role in the immune system process, in which 2'-5'-oligoadenylate synthetase-like, myxovirus resistance 1, myxovirus resistance 2, dynein cytoplasmic 1 intermediate chain 1, and coiled-coil domain containing 88B showed differential expression. The DEPs had demonstrated an augmentation in the signaling pathways, which primarily include phagosome, antigen processing, and presentation, as well as cell adhesion molecules (CAMs). Our study found that immune responses in the duodenum were enhanced by lower doses of boron and that this effect is likely mediated by changes in protein expression patterns in related signaling pathways. It offers an in-depth understanding of the underlying molecular mechanisms that lead to immune modulation in rats subjected to dietary boron treatment.

Corrigendum: High expression of PARP1 in tumor and stroma cells predicts prognosis and platinum resistance in patients with advanced epithelial ovarian cancer.

[This corrects the article DOI: 10.3389/fonc.2022.931445.].

Effect of Near-Liquidus Squeeze Casting Pressure on Microstructure and Mechanical Property of AZ91D Alloy Differential Support.

In this study, near-liquidus squeeze casting AZ91D alloy was used to prepare differential support, and the microstructure and mechanical behavior under different applied pressure were investigated. Under the preset temperature, speed, and other process parameters, the effect of applied pressure on the microstructure and properties of formed parts was analyzed, and relevant mechanism was also discussed. The results showed that the ultimate tensile strength (UTS) and elongation (EL) of differential support can be improved by controlling real-time precision of the forming pressure. The dislocation density in the primary phase increased obviously with the pressure increasing from 80 MPa to 170 MPa, and even tangles appeared. When the applied pressure increased from 80 MPa to 140 MPa, the α-Mg grains were gradually refined, and the microstructure changed from rosette to globular shape. With increasing the applied pressure to 170 MPa, the grain could not be further refined. Similarly, its UTS and EL gradually increased with the applied pressure increasing from 80 MPa to 140 MPa. With increasing to 170 MPa, the UTS tended to be constant, but the EL gradually decreased. In other words, the UTS (229.2 MPa) and EL (3.43%) of the alloy reached the maximum when the applied pressure was 140 MPa, and the comprehensive mechanical properties were the best.

Nocardia rubra cell-wall skeleton activates an immune response in cervical tissue via stimulating FPR3 to enhance dendritic cell-mediated Th1 differentiation.

Nocardia rubra cell wall skeleton (Nr-CWS) has proven to be a successful medicine for therapy of cervical human papillomavirus infection. The mechanism of action of Nr-CWS is unclear but may involve a stimulatory effect on the host immune system. We previously found that CD4+ T cells were increased in cervical tissue after Nr-CWS treatment. Microarray data from these cervical tissues revealed the significant upregulation of formylated peptide receptor 3 (FPR3). This study aimed to explore the role of Nr-CWS in immunomodulatory based on these findings. Examination of CD4+ T cell subsets in cervical tissue from patients who received Nr-CWS revealed substantial increases in Th1 cytokines and transcription factors. The regulatory effects of Nr-CWS on the function and phenotype of dendritic cells (DCs) were assessed in comparison with the traditional DC maturation inducer lipopolysaccharide (LPS). Similar to LPS, Nr-CWS potently induced DC maturation and interleukin-12 (IL-12) secretion. Differentiation of T cells induced by Nr-CWS stimulated DCs was assessed using the mixed lymphocyte reaction assay. Significant differentiation towards Th1 was evident. Finally, FPR3 expression in DCs in response to Nr-CWS and LPS was measured. Nr-CWS potently upregulated FPR3 expression, while the LPS did not. Silencing FPR3 in DCs reduced Nr-CWS-induced IL-12 production and Th1 cell polarization in co-cultured T cells. The collective findings indicate that Nr-CWS may target FPR3 on the surface of DC cells and activate a Th1-type immune response. The findings clarify the basis of the antiviral immune effects of Nr-CWS on human papillomavirus.

Hericium erinaceus polysaccharide improves the microstructure, immune function, proliferation and reduces apoptosis of thymus and spleen tissue cells of immunosuppressed mice.

In order to study the effect of Hericium erinaceus polysaccharide (HEP) on the immune and antioxidation functions of immunosuppressed mice. The control group received distilled water orally and the model and experimental groups I, II, and III received 0, 80, 160, and 320 mg/kg HEP respectively for a fortnight after re-molding with cyoclphosphnalide (CTX). Compared with the control group, the secretion of IL-2, IL-4, and IFN-γ, the activity or content of T-AOC, T-SOD, and GSH-PX, and the expression of PCNA mRNA in the thymus and spleen were reduced in immunosuppressed mice (P < .05 or P < .01). Compared with immunosuppressed mice, the levels of IL-2, IFN-γ, and GSH-PX and the PCNA mRNA expression of spleen and thymus were increased (P < .05 or P < .01), and the microstructure were also obviously improved in the experimental group III. Overall, 320 mg/kg of HEP significantly improved the immune and antioxidant functions.

Nocardia rubra cell wall skeleton regulates tumour-associated macrophage polarization by reprogramming M2 macrophages into M1 macrophages via STAT1/STAT6 pathways.

Targeted therapy with tumour-associated macrophages (TAMs) has emerged as a new paradigm for immunotherapy of cervical cancer. Nocardia rubra cell wall skeleton (Nr-CWS) for external use is an immunotherapeutic agent. In this study, we aimed to explore the effects of Nr-CWS on TAMs and the potential mechanisms. Cervical tissue samples were collected before and after Nr-CWS treatment from patients with high-risk HPV infection and cervical intraepithelial neoplasia (CIN). The effect of Nr-CWS on macrophages in vivo was examined by immunohistochemistry and double-labeling immunofluorescence histochemistry. In vitro experiments were performed using a TAM model established by THP-1 cells under Nr-CWS treatment. We found that Nr-CWS treatment significantly reduced the numbers of total macrophages and M2 macrophages, increased the proportion of M1 macrophages and decreased the proportion of M2 macrophages in cervical tissues. After Nr-CWS treatment in vitro, the expression levels of the M1 macrophage markers were increased, while the expression levels of the M2 macrophage markers were decreased. Nr-CWS treatment also activated STAT1 pathways but inhibited STAT6 pathways. These results indicated that Nr-CWS may improve local immune response and reverse immunosuppression by regulating the M2 to M1 polarization of TAMs via STAT1/STAT6 pathways.

The PPR-Domain Protein SOAR1 Regulates Salt Tolerance in Rice.

Previous studies in Arabidopsis reported that the PPR protein SOAR1 plays critical roles in plant response to salt stress. In this study, we reported that expression of the Arabidopsis SOAR1 (AtSOAR1) in rice significantly enhanced salt tolerance at seedling growth stage and promoted grain productivity under salt stress without affecting plant productivity under non-stressful conditions. The transgenic rice lines expressing AtSOAR1 exhibited increased ABA sensitivity in ABA-induced inhibition of seedling growth, and showed altered transcription and splicing of numerous genes associated with salt stress, which may explain salt tolerance of the transgenic plants. Further, we overexpressed the homologous gene of SOAR1 in rice, OsSOAR1, and showed that transgenic plants overexpressing OsSOAR1 enhanced salt tolerance at seedling growth stage. Five salt- and other abiotic stress-induced SOAR1-like PPRs were also identified. These data showed that the SOAR1-like PPR proteins are positively involved in plant response to salt stress and may be used for crop improvement in rice under salinity conditions through transgenic manipulation.

The phosphorylation level of Cofilin-1 is related to the pathological subtypes of gastric cancer.

The purpose of the study was to explore the relationship between multiple proteins belonging to the LIMK/Cofilin pathway, including LIMK1, LIMK2, Cofilin-1, and p-Cofilin-1 and clinical features of gastric cancer (GC) patients, including overall survival, TNM stages, and pathological subtypes. The expression of LIMK1, LIMK2, Cofilin-1 and p-Cofilin-1 in the GC tissues and adjacent normal stomach tissues from 141 patients were detected using immunohistochemistry (IHC) staining. Wilcoxon rank-sum test and Spearman rank correlation coefficients were used to measure the relationship between different TNM stages, pathological types, and selected parameters. OS was estimated using the Kaplan-Meier method and survival curves were compared using the log-rank test. Our results showed that, compared to those in the adjacent normal stomach tissues, LIMK1, LIMK2 and Cofilin-1 were up-regulated while p-Cofilin-1 was down-regulated in the GC tissues. LIMK1 level was positively correlated to the TNM stages of GC. According to the published dataset, the expression levels of both LIMK1 and LIMK2 were correlated to the overall survival time of GC patients. The level of Cofilin-1 was significantly different between GCs of different TNM stages. Moreover, most importantly, this is the first study to reveal that the level of Cofilin-1 is higher, and the level of p-Cofilin-1 is lower in the diffuse type of GC compared to that in intestinal type. Taken together, our study demonstrated that multiple factors in LIMK/Cofilin pathway including LIMK1, LIMK2, Cofilin-1, and p-Cofilin-1 were associated with the clinical and pathological features of GC, which is potentially helpful for the diagnosis and treatment of GC.

Role of gga-miR-29b-3p in suppressing the proliferation, invasion and migration of MSB1 Marek's disease tumor cells by the targeting of the DNMT3B gene.

Background: Marek's disease (MD), a class II infectious, lymphoproliferative disease that mainly afflicts poultry, has been shown to cause wasting, limb paralysis, and often acute death. It is a neoplastic disease caused by a cell-binding herpesvirus that leads to the formation of tumors in various organs and tissues. Our previous reports have found that the microRNA, gga-miR-29b-3p, showed abnormal expression in MD lymphoma. However, it remains unknown whether gga-miR-29b-3p affects MD tumorigenesis. Methods: The MD tumor cell line MSB1 was chosen to analyze the characteristics of gga-miR-29b-3p in tumors. Cell proliferation and migration were assessed by Cell Counting Kit-8 (CCK-8) and Transwell, respectively, and cell apoptosis and cycle were analyzed via fluorescent staining and flow cytometry, respectively. The regulation between gga-miR-29b-3p and its potential target genes was verified by dual luciferase results and loss-of-function assays. The effect of target genes was verified by examining the degree of RNA interference on MSB1 cells. Results: Analysis revealed that gga-miR-29b-3p impaired the proliferation of the MSB1 MD tumor cell line, induced apoptosis without obvious effects on the cell cycle, and suppressed the expression of the invasion-associated MMP2 and MMP9 genes. It was concluded that DNMT3B is the direct target of gga-miR-29b-3p. As expected, the effects of DNMT3B knockdown with small interfering RNA (siRNA) on MSB1 cell proliferation, apoptosis, and cycle were associated with gga-miR-29b-3p overexpression. Moreover, BCL2 and BCL2L1 were downregulated and TNFSF10 was upregulated in both the gga-miR-29b-3p overexpression and DNMT3B knockdown groups. The expression levels of invasion-related genes were decreased post-DNMT3B knockdown. In both the gga-miR-29b-3p overexpression and DNMT3B knockdown conditions, a decrease in MEQ oncogene expression in MD virus was observed. Conclusions: Overall, gga-miR-29b-3p was demonstrated to have a suppressive effect in MD lymphoma progression via the targeting of the DNMT3B gene. Gga-miR-29b-3p overexpression and DNMT3B knockdown inhibited MSB1 cell proliferation through suppressing the pro-apoptotic gene expression and elevating the anti-apoptotic gene expression in the apoptosis pathway. Our study provides a theoretical basis for targeted treatment of MD.

High Expression of PARP1 in Tumor and Stroma Cells Predicts Different Prognosis and Platinum Resistance in Patients With Advanced Epithelial Ovarian Cancer.

Objective: This study aimed to explore the roles of PARP1 mRNA and protein expression in platinum resistance and prognosis of EOC patients, and reveal the different roles of PARP1 protein in epithelial tumor and stroma cells. Methods: The PARP1 mRNA expression of the EOC tissues was examined by RT-qPCR. The impacts of PARP1 expression on prognosis were measured by Kaplan-Meier and Cox regression. Receiver operating characteristic (ROC) curve analysis was employed for calculating the diagnostic value of PARP1 on platinum resistance. The microarray of formalin-fixed, paraffin-embedded (FFPE) tissues was processed for multiplex immunofluorescence to detect the protein levels of PARP1 and cytokeratin (CK). Results: The PARP1mRNA expression of EOC patients was higher in the platinum-resistant group compared with the sensitive group (P<0.01). Kaplan-Meier analysis demonstrated that high PARP1 mRNA expression was associated with poor survival of EOC patients. In Cox regression analyses, high PARP1 mRNA expression independently predicted poor prognosis (P=0.001, HR=2.076, 95%CI=1.373-3.140). The area under the ROC curve of PARP1 mRNA for predicting the platinum resistance in EOC patients was 0.649, with a sensitivity of 0.607 and specificity of 0.668. Furthermore, the protein expression of PARP1 was higher in the platinum-resistant group than in the sensitive group (P<0.01) and associated with a worse prognosis. Additionally, according to CK labeling, we observed that enhanced expression of PARP1 in the CK+ region was associated with platinum resistance and lower survival, but in CK- region, it predicted a good prognosis and platinum sensitivity. Conclusion: PARP1 may be a potential biomarker to predict platinum resistance and prognosis for EOC patients, exerting different roles on epithelial tumor and stromal cells.

Co-functioning of 2AP precursor amino acids enhances 2-acetyl-1-pyrroline under salt stress in aromatic rice (Oryza sativa L.) cultivars.

Aromatic rice (Oryza sativa) fetches a premium price due to the pleasant aroma. The major aroma compound 2-acetyl-1-pyrroline (2AP) has been found to be enhanced under stress. This condition can be considered to study the genes, precursors, enzymes, and metabolites involved in elevated levels of 2AP biosynthesis. In the present study, 100 mM salt treatment was given to two aromatic rice cultivars Ambemohar-157 (A-157) and Basmati-370 (B-370) at the vegetative stage (VS3). After salt treatment, in the leaves, 2AP contents were elevated by 2.2 and 1.8 fold in A-157 and B-370, respectively. Under these elevated 2AP conditions, the precursor amino acids (glutamate, putrescine, ornithine, and proline), their related genes, enzymes, and metabolites (methylglyoxal and γ-aminobutyric acid (GABA) related to 2AP biosynthesis were analyzed. In addition, agronomic characters were also studied. It was observed that the proline content was enhanced in both the cultivars by 29% (A-157) and 40% (B-370) as compared to control. The Δ1-pyrroline-5-carboxylate synthetase (P5CS) enzyme activity was increased in salt-treated plants leaf tissue by 31% (A-157) and 40% (B-370) compared to control. The P5CS gene expression was enhanced by A-157 (1.8 fold) and B-370 (2.2 fold) compared to control, putrescine content in A-157 and B-370 decreased by 2.5 and 2.7 fold respectively as compared to control. The ornithine decarboxylase (ODC) activity was enhanced in A-157 (12%) and B-370 (35%) over control. Further, ODC gene expression was enhanced in both the cultivars A-157 (1.5 fold) and B-370 (1.3 fold). The diamino oxidase (DAO) enzyme activity was increased by 28% (A-157) and 35% (B-370) respectively over control. The GABA content marginally increased over control in both the cultivars namely, A-157 (1.9%) and B-370 (9.5%). The methylglyoxal levels were enhanced by 1.4 fold in A-157 and 1.6 fold in B-370. Interestingly, the enhancement in 2AP in the vegetative stage also helped to accumulate it in mature grains (twofold in A-157 and 1.5 fold in B-370) without test weight penalty. The study indicated that the ornithine and proline together along with methylglyoxal contribute towards the enhancement of 2AP under salt stress.

Comprehensive Transcriptome Analysis of GS3 Near-Isogenic Lines During Panicle Development in Rice (Oryza sativa L.).

Panicle architecture is an important agronomic trait in rice that affects rice yields and quality. The GRAIN SIZE 3 (GS3) locus has been identified as a major quantitative trait locus (QTL) affecting grain length and weight. The current understanding of the function of the GS3 gene, especially concerning the regulatory mechanism of panicle development, is still in its infancy. In this study, we generated GS3 near-isogenic lines (NILs) by successive crossing and backcrossing of TD70 (large grain) with Kasalath (small grain), using Kasalath as the recurrent parent. To identify potential transcription dynamic changes in rice panicle formation and grain shape, we deeply analyzed transcriptional profiles for the NILs (NIL-GS3 and NIL-gs3) at three different panicle developmental stages (S, M, and L). A total of 887, 1,768, and 1,478 differentially expressed genes (DEGs) were identified at stages S, M, and L, respectively. We also found 542 differential expressed long non-coding RNAs (lncRNAs). Co-expression analysis further revealed significant clusters associated with different development periods in NIL-gs3 lines. Gene Ontology and KEGG enrichment analysis revealed G-protein signaling and hormones pathway were successively activated at the M and L stages of NIL-gs3, which indicated activation of the G-protein signaling pathway might trigger the down-streaming hormone signaling transduction. we found that other hormones such ABA, Auxin, CK were significantly enriched in the L stage in the NIL-gs3. We highlighted the synergistic interplay of G-protein and multiple hormones signaling pathways and their essential roles in regulating rice panicle formation and the grain shape. Our study provides an invaluable resource for further molecular mechanistic studies that affect rice grain size and provide new insight for directed selection by marker-assisted backcross breeding.

Effects of konjac glucomannan/pomegranate peel extract composite coating on the quality and nutritional properties of fresh-cut kiwifruit and green bell pepper.

The effects of an edible coating, based on konjac glucomannan (KG) incorporated with pomegranate peel extracts (PE), on the physicochemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during storage were investigated. The optimal extract time (40.6 min), temperature (54.5 °C), and ultrasound power (255.5 W) with response surface method, provided a high total antioxidant activity (TAA) of (92.31 ± 1.43)%. Fresh-cut kiwifruit and green bell pepper were coated by dipping using five treatments (distilled water, ascorbic acid, KG, PE, KG + PE), packed into polymeric film and stored for 8 days at 10 °C. Distilled water treatment was used as control. KG + PE treatment resulted in the highest total soluble solid and titratable acidity in fresh-cut kiwifruit, while the maximum firmness in fresh-cut green bell pepper. The weight loss was both effectively decreased in samples treated with KG or KG + PE. All samples treated with KG + PE had significantly higher contents of chlorophyll, ascorbic acid, total phenolic and TAA than others. Moreover, the KG + PE group had the lowest counts of microorganisms in all samples. KG coating incorporated with PE was proved to be efficient in maintaining the physico-chemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during low temperature storage compared with control. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05006-7.