Soybean Factor Research Articles

Soybean Agglutinin Induced Apoptotic Effects by Down-Regulating ANXA2 Through FAK Pathway in IPEC-J2 Cells.

Soybean agglutinin (SBA) is an anti-nutritional factor in soybean, possesses toxic effects by binding to intestinal epithelial cells, and finally interferes the digestion and absorption of nutrients in humans and animals. Annexin A2 (ANXA2) is one of the SBA-specific binding proteins in intestinal epithelial cells and participates in multiple cellular biological processes. However, whether SBA affects apoptosis through ANXA2 and its apoptosis-related pathway remains unclear. IPEC-J2 is an ideal model to study human intestinal health. Therefore, this study aims to investigate the effects of ANXA2 on SBA-induced intestinal epithelial cell apoptosis and the related pathway mechanism using IPEC-J2 as a cell model. The results showed that SBA induced the apoptosis through FAK signal pathway and decreased the gene and protein expressions of ANXA2 in IPEC-J2. The expression of ANXA2 protein had a negative correlation with the apoptosis rates, and a positive correlation with the expression of FAK protein and FAK pathway downstream proteins. In conclusion, SBA induced apoptosis of IPEC-J2 cells by downregulating the expression of ANXA2, which activated the FAK pathway. These findings highlight the toxic mechanism of SBA, which will provide basis for studying the toxicity mechanisms of other food-derived anti-nutrients and provide a new perspective for human gastrointestinal health and related cancer treatment.

Development of a Phage-Displayed Nanobody-Based Competitive Immunoassay for the Sensitive Detection of Soybean Agglutinin.

Soybean agglutinin (SBA) is a primary antinutritional factor in soybeans that can inhibit the growth of humans and mammals, disrupt the intestinal environment, and cause pathological changes. Therefore, detecting and monitoring SBA in foods is essential for safeguarding human health. In this paper, M13 phage-displayed nanobodies against SBA were isolated from a naive nanobody library. An M13 phage-displayed nanobody-based competitive enzyme-linked immunosorbent assay (P-cELISA) was then established for SBA analysis using biotinylated anti-M13 phage antibody (biotin-anti-M13) and streptavidin poly-HRP conjugate (SA-poly-HRP). The biotin-anti-M13@SA-poly-HRP probe can easily amplify the detection signal without the chemical modifications of phage-displayed nanobodies. The established P-cELISA presented a linear detection range of 0.56-250.23 ng/mL and a limit of detection (LOD) of 0.20 ng/mL, which was 12.6-fold more sensitive than the traditional phage-ELISA. Moreover, the developed method showed good specificity for SBA and acceptable recoveries (78.21-121.11%) in spiked wheat flour, albumen powder, and whole milk powder. This study proposes that P-cELISA based on biotin-anti-M13@SA-poly-HRP may provide a convenient and effective strategy for the sensitive detection of SBA.

PSEUDO-RESPONSE REGULATOR 3b and transcription factor ABF3 modulate abscisic acid-dependent drought stress response in soybean.

The circadian system plays a pivotal role in facilitating the ability of crop plants to respond and adapt to fluctuations in their immediate environment effectively. Despite the increasing comprehension of PSEUDO-RESPONSE REGULATORs and their involvement in the regulation of diverse biological processes, including circadian rhythms, photoperiodic control of flowering, and responses to abiotic stress, the transcriptional networks associated with these factors in soybean (Glycine max (L.) Merr.) remain incompletely characterized. In this study, we provide empirical evidence highlighting the significance of GmPRR3b as a crucial mediator in regulating the circadian clock, drought stress response, and abscisic acid (ABA) signaling pathway in soybeans. A comprehensive analysis of DNA affinity purification sequencing and transcriptome data identified 795 putative target genes directly regulated by GmPRR3b. Among them, a total of 570 exhibited a significant correlation with the response to drought, and eight genes were involved in both the biosynthesis and signaling pathways of ABA. Notably, GmPRR3b played a pivotal role in the negative regulation of the drought response in soybeans by suppressing the expression of abscisic acid-responsive element-binding factor 3 (GmABF3). Additionally, the overexpression of GmABF3 exhibited an increased ability to tolerate drought conditions, and it also restored the hypersensitive phenotype of the GmPRR3b overexpressor. Consistently, studies on the manipulation of GmPRR3b gene expression and genome editing in plants revealed contrasting reactions to drought stress. The findings of our study collectively provide compelling evidence that emphasizes the significant contribution of the GmPRR3b-GmABF3 module in enhancing drought tolerance in soybean plants. Moreover, the transcriptional network of GmPRR3b provides valuable insights into the intricate interactions between this gene and the fundamental biological processes associated with plant adaptation to diverse environmental conditions.

A DIRIGENT Gene GmDIR26 Regulates Pod Dehiscence in Soybean.

Pod dehiscence brings much loss for modern agricultural production, and multiple pod dehiscence components have been identified in many plant species. However, the pod dehiscence regulation factors in soybean are limited. In this study, we investigate the function of GmDIR26, a close homologues gene of pod dehiscence genes GmPdh1, PvPdh1, and CaPdh1, in the regulation of pod dehiscence in soybean. The secondary and tertiary structure analysis reveals that GmDIR26 protein has a similar structure with GmPdh1, PvPdh1, and CaPdh1 proteins. Synteny analysis of soybean and chickpea genomes shows that the genomic region surrounding GmDIR26 and CaPdh1 might be evolved from the same ancestor, and these two genes might have similar function. GmDIR26 shows an increased expression pattern during pod development and reaches a peak at beginning seed stage. Meanwhile, GmDIR26 exhibits high expression levels in dorsal suture and pod wall, but low expression pattern in ventral suture. In addition, GmDIR26 shows higher expression levels in pod dehiscence genotype than that in pod indehiscence accessions. Overexpression of GmDIR26 in soybean increases pod dehiscence in transgenic plants, of which the lignin layer in inner sclerenchyma pods is thicker and looser. The expression levels of several pod dehiscence genes are altered. Our study provides important information for further modification of pod dehiscence resistance soybean and characterization of soybean pod dehiscence regulation network.

The apoptotic effects of soybean agglutinin were induced through three different signal pathways by down-regulating cytoskeleton proteins in IPEC-J2 cells

Soybean agglutinin (SBA) is a main anti-nutritional factor in soybean. SBA exhibits its anti-nutritional functions by binding to intestinal epithelial cells. Keratin8 (KRT8), Keratin18 (KRT18) and Actin (ACTA) are the representative SBA-specific binding proteins. Such cytoskeletal proteins act a crucial role in different cell activities. However, limited reports reveal what the signal transduction pathway of apoptosis caused by SBA when binding to KRT8, KRT18 and ACTA. We aimed to evaluate the effects of SBA on cell apoptosis and the expression of the cytoskeletal protein (KRT8, KRT18 and ACTA), reveal the roles of these cytoskeletal proteins or their combinations on SBA-induced cell apoptosis in IPEC-J2 cell line, evaluate the influences of SBA on the mitochondria, endoplasmic reticulum stress and death receptor-mediated apoptosis signal pathway and to show the roles of KRT8, KRT18 and ACTA in different apoptosis signal pathways induced by SBA. The results showed that SBA induced the IPEC-J2 cell apoptosis and decreased the mRNA expression of KRT8, KRT18 and ACTA (p < 0.05). The degree of effect of three cytoskeleton proteins on cell apoptosis was ACTA > KRT8 > KRT18. The roles of these three cytoskeletal proteins on IPEC-J2 apoptotic rates had a certain accumulation effect. SBA up-regulated mitochondrial fission variant protein (FIS1) and fusion protein (Mfn2) promoted CytC and AIF in mitochondria to enter the cytoplasm, activated caspase-9 and caspase-3, damaged or declined mitochondrial function and reduced ATP synthesis (p < 0.05). Also, SBA up-regulated the expression of GRP78, XBP-1, eIF2α, p-eIF2α and CHOP (p < 0.05), down-regulated the expression level of ASK1 protein (p < 0.05). SBA led to the recruitment of FADD to the cytoplasmic membrane and increased the expression of FasL, resulting in caspase-8 processing. SBA up-regulated the expression level of Bax protein and decreased cytosolic Bcl-2 and Bid (p < 0.05). In addition, there was a significant negative correlation between the gene expression of cytoskeleton proteins and apoptosis, as well as the expression of key proteins of apoptosis-related signal transduction pathways. In conclusion, SBA induced the activation of the mitochondria, endoplasmic reticulum stress and the death receptor-mediated apoptosis signal pathway and the crosstalk between them. The effect of SBA on these three pathways was mainly exhibited via down-regulation of the mRNA expression of the three cytoskeletal expressions. This study elucidates the molecular mechanism and signaling pathway of SBA that lead to apoptosis from the perspective of cell biology and molecular biology and provides a new perspective on the toxicity mechanism of other food-derived anti-nutrients, medical gastrointestinal health and related cancer treatment.

Genome-Wide Identification and Expression Characteristics of Cytokinin Response Factors in Soybean

Genome-Wide Identification and Expression Characteristics of Cytokinin Response Factors in Soybean

MADS-Box Subfamily Gene GmAP3 from Glycine max Regulates Early Flowering and Flower Development.

AP3 has been studied and is reported to affect structural changes in floral organs in various plants. However, the function of the soybean AP3 genes in flower development is unknown. Here, the full-length cDNA sequence of GmAP3 was obtained by RACE and it was verified that it belongs to the MADS-box subfamily by a bioinformatics analysis. The expression of GmAP3 is closely related to the expression of essential enzyme genes related to flower development. Yeast two-hybrid assays demonstrated that GmAP3 interacts with AP1 to determine the identity of flower organ development. A follow-up analysis showed that overexpression of the GmAP3 gene advanced flowering time and resulted in changes in floral organ morphology. The average flowering time of overexpressed soybean and tobacco plants was 6-8 days earlier than that of wild-type plants, and the average flowering time of gene-edited soybean and tobacco plants was 6-11 days later than that of wild-type plants. In conclusion, GmAP3 may directly or indirectly affect the flower development of soybean. The results of this study lay the foundation for further research on the biological functions of MADS transcriptional factors in soybeans.

Identification and Molecular Characterization of RWP-RK Transcription Factors in Soybean.

The RWP-RK is a small family of plant-specific transcription factors that are mainly involved in nitrate starvation responses, gametogenesis, and root nodulation. To date, the molecular mechanisms underpinning nitrate-regulated gene expression in many plant species have been extensively studied. However, the regulation of nodulation-specific NIN proteins during nodulation and rhizobial infection under nitrogen starvation in soybean still remain unclear. Here, we investigated the genome-wide identification of RWP-RK transcription factors and their essential role in nitrate-inducible and stress-responsive gene expression in soybean. In total, 28 RWP-RK genes were identified from the soybean genome, which were unevenly distributed on 20 chromosomes from 5 distinct groups during phylogeny classification. The conserved topology of RWP-RK protein motifs, cis-acting elements, and functional annotation has led to their potential as key regulators during plant growth, development, and diverse stress responses. The RNA-seq data revealed that the up-regulation of GmRWP-RK genes in the nodules indicated that these genes might play crucial roles during root nodulation in soybean. Furthermore, qRT-PCR analysis revealed that most GmRWP-RK genes under Phytophthora sojae infection and diverse environmental conditions (such as heat, nitrogen, and salt) were significantly induced, thus opening a new window of possibilities into their regulatory roles in adaptation mechanisms that allow soybean to tolerate biotic and abiotic stress. In addition, the dual luciferase assay indicated that GmRWP-RK1 and GmRWP-RK2 efficiently bind to the promoters of GmYUC2, GmSPL9, and GmNIN, highlighting their possible involvement in nodule formation. Together, our findings provide novel insights into the functional role of the RWP-RK family during defense responses and root nodulation in soybean.

Dietary yeast culture alleviates intestinal-hepatic damage related to TLR2-MyD88-NF-κB signaling pathway and antioxidant capability in Pseudobagrus ussuriensis

Yeast culture (YC), as a member of probiotics family is a natural product produced from yeast fermentation, affects of improving immunity. However, the intestine and liver injury and immunosuppression mechanism caused by SBA in fish are unclear and more functions of YC supplement in the diet need to be developed. Soybean agglutinin (SBA) is an anti-nutritional factor in soybean and leads to growth-inhibitory effect in feeding of the high proportion of soybean meal replacing fish meal (FM). Therefore, one hundred and thirty-five Pseudobagrus ussuriensis (6.5 ± 0.27 g) were randomly selected and divided into three groups (Control, SBA and YC+SBA groups). For the model, fish were fed with 2% YC for 8 weeks and then given intragastric administration of 0.2-mL SBA solution for 20 days. The results showed that SBA damaged the immune and antioxidant capacity, causing an inflammatory reaction, leading to abnormal expression of cytokines in the intestine and liver of Pseudobagrus ussuriensis. YC could effectively attenuate intestinal and liver damage and downregulate the TLR2/MyD88/NF-κB signaling pathway and suppress oxidative stress in Pseudobagrus ussuriensis. Besides, YC had obvious immune advantage, which could improve the immune ability. In summary, these results showed that YC could reduce immunosuppression and intestinal-liver injury by inhibiting the TLR2/MyD88/NF-κB signal pathway and oxidative stress induced by SBA. This study provided some explanations for the problems of fish diet caused by anti-nutritional factors from soybean meal and provided a theoretical basis for the function development of YC in aquaculture.

Photosynthetic Physiology Performance and Expression of Transcription Factors in Soybean of Water Use Efficiency Difference

Photosynthetic Physiology Performance and Expression of Transcription Factors in Soybean of Water Use Efficiency Difference

Quantification of lectin in soybeans and soy products by liquid chromatography-tandem mass spectrometry

Lectin is one of the major anti-nutritional factors in soybeans and inhibits digestion of dietary protein. Here, an absolute quantification method was developed to detect lectin using synthetic peptide 183TTSWDLANNK192 as reference standard and corresponding isotope labeled peptide TTSWDLANNK (Alanine-13C3,15N) as internal standard to normalize results. After the ground soybeans and soy products were defatted with n-hexane and extracted with extraction buffer, the crude protein extract was digested on filter membrane by trypsin. Further, the enzymatic hydrolysis peptides were quantified using liquid chromatography-tandem mass spectrometry. The synthetic reference peptide showed a detection limit of 0.27 ng/mL and a linear relationship in the range of 3.2–1000 ng/mL (r2 > 0.997). Correspondingly, the detect limit of lectin in soybean samples was 35.5 μg/g. The results showed that the recoveries of the lectin in spiked samples ranged from 80.9% to 108.7% with intra-day precisions (% CV) less than 9%. The method was successfully used to evaluate lectin levels in hundreds of soybean seeds from different varieties and soy products from different soybean processing techniques. Furthermore, the method may provide a potential application as a general method for the ultrasensitive detection of various protein anti-nutritional factors in food.

Development of Breeder-Friendly KASP Markers for Low Concentration of Kunitz Trypsin Inhibitor in Soybean Seeds.

Trypsin inhibitors (TI), a common anti-nutritional factor in soybean, prevent animals’ protein digestibility reducing animal growth performance. No commercial soybean cultivars with low or null concentration of TI are available. The availability of a high throughput genotyping assay will be beneficial to incorporate the low TI trait into elite breeding lines. The aim of this study is to develop and validate a breeder friendly Kompetitive Allele Specific PCR (KASP) assay linked to low Kunitz trypsin inhibitor (KTI) in soybean seeds. A total of 200 F3:5 lines derived from PI 547656 (low KTI) X Glenn (normal KTI) were genotyped using the BARCSoySNP6K_v2 Beadchip. F3:4 and F3:5 lines were grown in Blacksburg and Orange, Virginia in three years, respectively, and were measured for KTI content using a quantitative HPLC method. We identified three SNP markers tightly linked to the major QTL associated to low KTI in the mapping population. Based on these SNPs, we developed and validated the KASP assays in a set of 93 diverse germplasm accessions. The marker Gm08_44814503 has 86% selection efficiency for the accessions with low KTI and could be used in marker assisted breeding to facilitate the incorporation of low KTI content in soybean seeds.

Anti-nutritional characteristics and mechanism of soybean agglutinin

Soybean agglutinin (SBA) is an important anti-nutritional factor in soybean. SBA can induce animal growth inhibition, cause pathological changes of intestinal tissue, and decrease in the immune system functioning. Recently, a... | Find, read and cite all the research you need on Tech Science Press

PSIX-15 Extrusion of corn-soybean product blends in replacement of soybean meal in weanling pig diets

Abstract Extrusion is a thermomechanical process that can reduce the content antinutritional factors in soybean, improving the use of its nutrients by pigs. The purpose of this study was to evaluate extruded corn-soybean grain blends, replacing soybean meal in weanling pig diets, on pig growth performance from 21 to 63 d old. Ground corn and the corn-soybean blend (75.27% of ground corn and 24.73%) were extruded at 120°C in a single-screw extruder. One hundred and sixty crossbred weaned pigs (6.02 ± 0.63 kg) were used in a three-phase feeding program (21-35, 36-49, 50-63 days of age) and fed a basal diet (BD - extruded corn, dairy product, spray dried plasma, and soybean meal) or one of four diets in which soybean meal was replaced for deactivated (DS) or extruded (EX) corn-soybean blend, in 50 or 100%, generating diets DS50, DS100, EX50 and EX100. Diets were formulated to provide 3.40, 3.38, and 3.20 Mcal of ME/kg; 220, 215, and 190 g/kg of CP; and 14.5, 13.3, and 10.9 g/kg of digestible lysine, in phases 1, 2, and 3, respectively. A randomized block design based on initial BW was used. The data was submitted to ANOVA and means were separated using Tukey test (5%). Pigs fed diets EX50 and EX100 presented reductions (P&amp;lt; 0.05) in ADG (16-50%), final BW and G:F (13-33%) compared to pigs submitted to diets SBM100, DS50 or DS100 in phases 1 and 2. ADG, ADFI, and G:F of pigs were not affected (P &amp;gt;0.05) in phase 3, but final BW of pigs fed extruded corn-soybean blend were lower (P&amp;lt; 0.05) than that of pigs fed other diets. The extrusion temperature may have been insufficient to inactivate the anti-nutritional factors of soybean that probably reduced pig growth performance. The inclusion of extruded corn-soybean blend in replacement of soybean meal reduced growth performance of pigs.

PSI-12 Effect of a carbohydrase mixture on apparent and standardized ileal digestibility of amino acids in dry extruded-expelled soybean meal fed to growing pigs

Abstract Heat treatment could effectively decrease the antinutritional factors in soybean during meal processing. One such progress is the combination of extrusion with expelling, which produces the dry extruded-expelled soybean meal (DESBM), and there is a great interest in exploring its utilization as a dietary ingredient for swine. Thus, eight ileal-cannulated barrows (initial BW = 30 ± 1.3 kg) were used to determine the ileal amino acid (AA) digestibility of DESBM fed to growing pigs with or without multi-carbohydrase (MC) supplementation. Pigs were randomly assigned to 1 of 4 treatments in a replicated 4 × 4 Latin square design to give eight observations per treatment. The experimental diets were formulated to contain one of the two batches of DESBM (DESBM-1 and DESBM-2) as the sole source of protein. All diets contained titanium dioxide (0.3%) as an indigestible marker to calculate nutrient digestibility. Each experimental period lasted for seven days, and ileal digesta samples were collected on d 6 and d 7. The standardized ileal digestibility (SID) of AA were calculated using published mean values to estimate ileal endogenous AA losses. Data were analyzed using the mixed model procedures of SAS, and the final model had treatment, batch, and the interaction between treatment and batch as the main effects. In general, the SID of AA in DESBM-1 and DESBM-2 were not different, such as Ile, Lys, Met, Thr, and Val, which averaged 88.97%, 89.77%, 89.08%, 84.38%, and 86.85% respectively. There were no effects of MC supplementation on AID and SID of AA digestibility in DESBM except for the AID of Trp (P &amp;lt; 0.05). Also, there were no interaction effects of MC supplementation and batch on AA digestibility in DESBM. In conclusion, enzyme supplementation did not improve the AID and SID of AA in DESBM fed to growing pigs.

Effect of Different Thermal and Non-Thermal Treatments on Total Phenols and Antioxidant Content of Soybean

Soybean is the most explored commodity for protein and fat as well as for obtaining products like soymilk and tofu. However, the presence ofanti-nutritional factors in soybean is not favorableand these are needed to be inactivated. Similarly, soybean is known for potential source of isoflavones, total phenolics and antioxidants.To inactivate anti-nutritional factorsdifferent treatments had been applied and consequently their corresponding effect on total phenolics (TP) and antioxidant capacity (AOC) were studied. High Pressure Processing (HPP), autoclave and microwave boiling treatments wereemployed to the soybean samples in soaked condition, and correspondingly their TP and AOC were estimated. HPP was not observed to affect the TP and AOC content significantly. The microwave treatment was observed to be affecting the TP and AOC but did not exhibit any severe effect while autoclave boiling lead to degradation of the bioactive by more than 50% and it was found to be severe. Conclusively, HPP was found to be suitable treatment to inactivate anti-nutritional factor and retain the bioactives like TP and AOC. The most elevated concentration of phenolic was acquired for HPP treatment at 400 Mpa for 10 min (1.88 mg/100g of the sample) and was almost similar to 400 Mpa for 5 min(1.87 mg /100g of the sample) and was observed that at higher pressure treatment time was not significant. The antioxidant capacity of the grains was similarly affected by the other processing techniques, but maximum was observed for raw sample (230.56 mg/100g of the sample). The autoclaveboilingimpaired severely total phenolics, and antioxidant capacity and it was observed to be 1.07mg/100 g of sample and 94.77 mg/100 g of the sample, respectively.

Unraveling the genetic architecture for carbon and nitrogen related traits and leaf hydraulic conductance in soybean using genome-wide association analyses

BackgroundDrought stress is a major limiting factor of soybean [Glycine max (L.) Merr.] production around the world. Soybean plants can ameliorate this stress with improved water-saving, sustained N2 fixation during water deficits, and/or limited leaf hydraulic conductance. In this study, carbon isotope composition (δ13C), which can relate to variation in water-saving capability, was measured. Additionally, nitrogen isotope composition (δ15N) and nitrogen concentration that relate to nitrogen fixation were evaluated. Decrease in transpiration rate (DTR) of de-rooted soybean shoots in a silver nitrate (AgNO3) solution compared to deionized water under high vapor pressure deficit (VPD) conditions was used as a surrogate measurement for limited leaf hydraulic conductance. A panel of over 200 genetically diverse soybean accessions genotyped with the SoySNP50K iSelect BeadChips was evaluated for the carbon and nitrogen related traits in two field environments (Athens, GA in 2015 and 2016) and for transpiration response to AgNO3 in a growth chamber. A multiple loci linear mixed model was implemented in FarmCPU to perform genome-wide association analyses for these traits.ResultsThirty two, 23, 26, and nine loci for δ13C, δ15N, nitrogen concentration, and transpiration response to AgNO3, respectively, were significantly associated with these traits. Candidate genes that relate to drought stress tolerance enhancement or response were identified near certain loci that could be targets for improving and understanding these traits. Soybean accessions with favorable breeding values were also identified. Low correlations were observed between many of the traits and the genetic loci associated with each trait were largely unique, indicating that these drought tolerance related traits are governed by different genetic loci.ConclusionsThe genomic regions and germplasm identified in this study can be used by breeders to understand the genetic architecture for these traits and to improve soybean drought tolerance. Phenotyping resources needed, trait heritability, and relationship to the target environment should be considered before deciding which of these traits to ultimately employ in a specific breeding program. Potential marker-assisted selection efforts could focus on loci which explain the greatest amount of phenotypic variation for each trait, but may be challenging due to the quantitative nature of these traits.

Genome-wide identification and evolutionary analysis of TGA transcription factors in soybean

The gain of function in genes and gene families is a continuous process and is a key factor in understanding gene and genome evolution in plants. TGACG-Binding (TGA) transcription factors (TFs) have long been known for their essential roles in plant defence in Arabidopsis, but their roles in legume symbiosis are yet to be explored. Here, we identified a total of 25 TGA (named GmTGA1-GmTGA25) genes in soybean. Through phylogenetic analysis, we discovered a clade of GmTGA proteins that appear to be legume-specific. Among them, two GmTGAs were unique by possessing the autophagy sequence in their proteins, while the third one was an orphan gene in soybean. GmTGAs were structurally different from AtTGAs, and their expression patterns also differed with the dominant expression of AtTGAs and GmTGAs in aerial and underground parts, respectively. Moreover, twenty-five GmTGAs showed a strong correlation among the gene expression in roots, nodules, and root hairs. The qRT-PCR analysis results revealed that among 15 tested GmTGAs, six were induced and four were suppressed by rhizobia inoculation, while 11 of these GmTGAs were induced by high nitrate. Our findings suggested the important roles of GmTGAs in symbiotic nodulation and in response to nitrogen availability in soybean.

Genome-wide identification of GRF transcription factors in soybean and expression analysis of GmGRF family under shade stress

BackgroundThe Growth-regulating factor (GRF) family encodes plant-specific transcription factors which contain two conserved domains, QLQ and WRC. Members of this family play vital roles in plant development and stress response processes. Although GRFs have been identified in various plant species, we still know little about the GRF family in soybean (Glycine max).ResultsIn the present study, 22 GmGRFs distributed on 14 chromosomes and one scaffold were identified by searching soybean genome database and were clustered into five subgroups according to their phylogenetic relationships. GmGRFs belonging to the same subgroup shared a similar motif composition and gene structure. Synteny analysis revealed that large-scale duplications played key roles in the expansion of the GmGRF family. Tissue-specific expression data showed that GmGRFs were strongly expressed in growing tissues, including the shoot apical meristems, developing seeds and flowers, indicating that GmGRFs play critical roles in plant growth and development. On the basis of expression analysis of GmGRFs under shade conditions, we found that all GmGRFs responded to shade stress. Most GmGRFs were down-regulated in soybean leaves after shade treatment.ConclusionsTaken together, this research systematically analyzed the characterization of the GmGRF family and its primary roles in soybean development and shade stress response. Further studies of the function of the GmGRFs in the growth, development and stress tolerance of soybean, especially under shade stress, will be valuable.

In vivo study of plant protein products from soybeans and non-alkaloid lupine Dega variety

Research on finding additional sources of vegetable protein as an alternative to soy has shown a great prospect of using lupine. The study of biological effects of flour of nonalkaloid lupine Dega variety will assess the future prospects for its use in food industry. The aim - a comparative study of protein products - soybean flour and non-alkaloid lupine flour (Dega-1 variety), added to laboratory rats' diet. Material and methods. Experiment was carried out on three groups of Wistar rats (n=30, 210±5 g) for 28 days: 1st group - rats that consumed the standard vivarium diet (control); 2nd group and 3rd group - animals, that consumed standard diet with addition of lupine flour (protein content - 42.1%) and soy flour (protein content - 50.2%), replacing 26 and 23% protein in standard diet, respectively. Results. As a result of the experiment, fluctuations in body weight of rats in 2nd group and 3rd group were observed from the 11th day; the weight gain of rats in 1st group was 7.74%, 2nd group and 3rd group - 3.32 and 2.04%. Noted changes could be explained by food adaptation of organism to the main nutrients of protein products. The blood test showed minor changes in the hematological and biochemical parameters within physiological reference values. Consumption of lupine flour led to a slight increase of leukocytes (by 14.2%) and lymphocytes (by 24.5%), an increase in the activity of certain enzymes (aspartate aminotransferase by 18.4%, alanine aminotransferase by 26.2% and lactate dehydrogenase by 21.6%, p≥0.05), while alkaline phosphatase activity decreased (14.4%, p<0.05) in comparison with control. Incorporation of soy flour into the diet of rats showed a statistically significant increase in the concentration of monocytes, eosinophils, basophils and immature cells (by 57.1% in comparison with 1st group and 83.3% in comparison with 2nd group), while relative content of granulocytes reduced (by 15.1% relative to the control). Conclusion. The inclusion of plant proteins into the rat's diet did not cause significant deviations in physiological (motor activity), biochemical, hematological parameters in experimental animals. However, the identified features in animals of the experimental groups, possibly related to biologically active substances and anti-alimentary factors in soybean and lupine, indicate the need to improve technological approaches to lupine protein products production in order to improve functional characteristics and completely remove substances that deteriorate nutrients absorption. A possible solution is lupine proteins' proteolysis, the use of various methods of fractionation, isolation and purification in combination with pretreatment to obtain protein concentrates or isolates with improved nutritional, technological and functional properties.