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A soybean elongation factor Tu family (EF-Tu) protein, GmEF8, was determined to interact with GmCBL1, and GmEF8 expression was found to be induced by various abiotic stresses such as drought and heat. An ortholog of GmEF8 was identified in Arabidopsis, a T-DNA knockout line for which exhibited hypersensitivity to drought and heat stresses. Complementation with GmEF8 rescued the sensitivity of the Arabidopsis mutant to drought and heat stresses, and GmEF8 overexpression conferred drought and heat tolerance to transgenic Arabidopsis plants. In soybean, plants with GmEF8-overexpressing hairy roots (OE-GmEF8) exhibited enhanced drought and heat tolerance and had higher proline levels compared to plants with RNAi GmEF8-knockdown hairy roots (MR-GmEF8) and control hairy roots (EV). A number of drought-responsive genes, such as GmRD22 and GmP5CS, were induced in the OE-GmEF8 line compared to MR-GmEF8 and EV under normal growth conditions. These results suggest that GmEF8 has a positive role in regulating drought and heat stresses in Arabidopsis and soybean. This study reveals a potential role of the soybean GmEF8 gene in response to abiotic stresses, providing a foundation for further investigation into the complexities of stress signal transduction pathways.

Summary Drought and salt stresses impose major constraints on soybean production worldwide. However, improving agronomically valuable soybean traits under drought conditions can be challenging due to trait complexity and multiple factors that influence yield. Here, we identified a nuclear factor Y C subunit (NF‐YC) family transcription factor member, GmNF‐YC14, which formed a heterotrimer with GmNF‐YA16 and GmNF‐YB2 to activate the GmPYR1‐mediated abscisic acid (ABA) signalling pathway to regulate stress tolerance in soybean. Notably, we found that CRISPR/Cas9‐generated GmNF‐YC14 knockout mutants were more sensitive to drought than wild‐type soybean plants. Furthermore, field trials showed that overexpression of GmNF‐YC14 or GmPYR1 could increase yield per plant, grain plumpness, and stem base circumference, thus indicating improved adaptation of soybean plants to drought conditions. Taken together, our findings expand the known functional scope of the NF‐Y transcription factor functions and raise important questions about the integration of ABA signalling pathways in plants. Moreover, GmNF‐YC14 and GmPYR1 have potential for application in the improvement of drought tolerance in soybean plants.

Tubby-like proteins (TLPs) are transcription factors that are widely present in eukaryotes and generally participate in growth and developmental processes. Using genome databases, a total of 22 putative

NF-YA transcription factors function in modulating tolerance to abiotic stresses that are serious threats to crop yields. In this study, GmNFYA13, an NF-YA gene in soybean, was strongly induced by salt, drought, ABA, and H2O2, and suppressed by tungstate, an ABA synthesis inhibitor. The GmNFYA13 transcripts were detected in different tissues in seedling and flowering stages, and the expression levels in roots were highest. GmNFYA13 is a nuclear localization protein with self-activating activity. Transgenic Arabidopsis plants overexpressing GmNFYA13 with higher transcript levels of stress-related genes showed ABA hypersensitivity and enhanced tolerance to salt and drought stresses compared with WT plants. Moreover, overexpression of GmNFYA13 resulted in higher salt and drought tolerance in OE soybean plants, while suppressing it produced the opposite results. In addition, GmNFYA13 could bind to the promoters of GmSALT3, GmMYB84, GmNCED3, and GmRbohB to regulate their expression abundance in vivo. The data in this study suggested that GmNFYA13 enhanced salt and drought tolerance in soybean plants.

Background Ethylene-responsive factors (ERFs) play important roles in plant growth and development and the response to adverse environmental factors, including abiotic and biotic stresses. Results In the present study, we identified 160 soybean ERF genes distributed across 20 chromosomes that could be clustered into eight groups based on phylogenetic relationships. A highly ABA-responsive ERF gene, GmERF75, belonging to Group VII was further characterized. Subcellular localization analysis showed that the GmERF75 protein is localized in the nucleus, and qRT-PCR results showed that GmERF75 is responsive to multiple abiotic stresses and exogenous hormones. GmERF75-overexpressing Arabidopsis lines showed higher chlorophyll content compared to WT and mutants under osmotic stress. Two independent Arabidopsis mutations of AtERF71, a gene homologous to GmERF75, displayed shorter hypocotyls, and overexpression of GmERF75 in these mutants could rescue the short hypocotyl phenotypes. Overexpressing GmERF75 in soybean hairy roots improved root growth under exogenous ABA and salt stress. Conclusions These results suggested that GmERF75 is an important plant transcription factor that plays a critical role in enhancing osmotic tolerance in both Arabidopsis and soybean.

Abscisic acid (ABA) mediates various abiotic stress responses, and ethylene responsive factors (ERFs) play vital role in resisting stresses, but the interaction of these molecular mechanisms remains elusive. In this study, we identified an ABA-induced soybean ERF gene GmERF135 that was highly up-regulated by ethylene (ET), drought, salt, and low temperature treatments. Subcellular localization assay showed that the GmERF135 protein was targeted to the nucleus. Promoter cis-acting elements analysis suggested that numerous potential stress responsive cis-elements were distributed in the promoter region of GmERF135, including ABA-, light-, ET-, gibberellin (GA)-, and methyl jasmonate (MeJA)-responsive elements. Overexpression of GmERF135 in Arabidopsis enhanced tolerance to drought and salt conditions. In addition, GmERF135 promoted the growth of transgenic hairy roots under salt and exogenous ABA conditions. These results suggest that soybean GmERF135 may participate in both ABA and ET signaling pathways to regulate the responses to multiple stresses.

WRKY transcription factors constitute one of the largest transcription factor families in plants, and play crucial roles in plant growth and development, defense regulation and stress responses. However, knowledge about this family in maize is limited. In the present study, we identified a drought-induced WRKY gene, ZmWRKY106, based on the maize drought de novo transcriptome sequencing data. ZmWRKY106 was identified as part of the WRKYII group, and a phylogenetic tree analysis showed that ZmWRKY106 was closer to OsWRKY13. The subcellular localization of ZmWRKY106 was only observed in the nucleus. The promoter region of ZmWRKY106 included the C-repeat/dehydration responsive element (DRE), low-temperature responsive element (LTR), MBS, and TCA-elements, which possibly participate in drought, cold, and salicylic acid (SA) stress responses. The expression of ZmWRKY106 was induced significantly by drought, high temperature, and exogenous abscisic acid (ABA), but was weakly induced by salt. Overexpression of ZmWRKY106 improved the tolerance to drought and heat in transgenic Arabidopsis by regulating stress-related genes through the ABA-signaling pathway, and the reactive oxygen species (ROS) content in transgenic lines was reduced by enhancing the activities of superoxide dismutase (SOD), peroxide dismutase (POD), and catalase (CAT) under drought stress. This suggested that ZmWRKY106 was involved in multiple abiotic stress response pathways and acted as a positive factor under drought and heat stress.

Abiotic stresses restrict the growth and yield of crops. Plants have developed a number of regulatory mechanisms to respond to these stresses. WRKY transcription factors (TFs) are plant-specific transcription factors that play essential roles in multiple plant processes, including abiotic stress response. At present, little information regarding drought-related WRKY genes in maize is available. In this study, we identified a WRKY transcription factor gene from maize, named ZmWRKY40. ZmWRKY40 is a member of WRKY group II, localized in the nucleus of mesophyll protoplasts. Several stress-related transcriptional regulatory elements existed in the promoter region of ZmWRKY40. ZmWRKY40 was induced by drought, high salinity, high temperature, and abscisic acid (ABA). ZmWRKY40 could rapidly respond to drought with peak levels (more than 10-fold) at 1 h after treatment. Overexpression of ZmWRKY40 improved drought tolerance in transgenic Arabidopsis by regulating stress-related genes, and the reactive oxygen species (ROS) content in transgenic lines was reduced by enhancing the activities of peroxide dismutase (POD) and catalase (CAT) under drought stress. According to the results, the present study may provide a candidate gene involved in the drought stress response and a theoretical basis to understand the mechanisms of ZmWRKY40 in response to abiotic stresses in maize.

In order to study the feasibility of using digital image analysis and machine learning algorithm to estimate leaf nitrogen accumulation (LNA) of winter wheat at canopy level, digital images of winter wheat canopies grown under six levels of nitrogen application rate were taken for four times during the elongation stage. Meanwhile, wheat plants were sampled to measure LNA. The random forest method using CIEL*a*b* components was used to segment wheat plant from soil background and then extract canopy cover, RGB components of sRGB color space and compute five color indices derived from RGB components. Correlation analysis was carried out to identify the relationship between LNA and canopy cover (CC), RGB components, and five color indices. Two kinds of nonlinear least squares regression models (NLS) with different independent variables of color components and color indices, and three machine learning algorithmic of artificial neural network (ANN), support vector regression (SVR), and random forests method (RF) were used to estimate winter wheat leaf nitrogen accumulation. All three machine learning algorithm had four input variables of CC, R, G, and B. The results showed that, CC, R and G component of sRGB color space, and five color indices derived from RGB components showed significant correlations with LNA during the elongation stage. CC revealed the highest correlation with LNA. The lowest accuracy in estimation LNA was achieved by using nonlinear least square model with CC and color indices, and RF had showed the problem of overfitting. The other three methods of LNA with CC and RGB components, ANN, and SVR had showed good performance with higher R2 (0.851, 0.845, and 0.862) and lower RMSE (19.440, 19.820, and 18.698) for model calibration and validation, revealing good generalization ability.

Abiotic stresses restrict the growth and yield of crops. Plants have developed a number of regulatory mechanisms to respond to these stresses. WRKY transcription factors (TFs) are plant-specific transcription factors that play essential roles in multiple plant processes, including abiotic stress response. At present, little information regarding drought-related WRKY genes in maize is available. In this study, we identified a WRKY transcription factor gene from maize, named ZmWRKY40. ZmWRKY40 is a member of WRKY group II, localized in the nucleus of mesophyll protoplasts. Several stress-related transcriptional regulatory elements existed in the promoter region of ZmWRKY40. ZmWRKY40 was induced by drought, high salinity, high temperature, and abscisic acid (ABA). ZmWRKY40 could rapidly respond to drought with peak levels (more than 10-fold) at 1 h after treatment. Overexpression of ZmWRKY40 improved drought tolerance in transgenic Arabidopsis by regulating stress-related genes, and the reactive oxygen species (ROS) content in transgenic lines was reduced by enhancing the activities of peroxide dismutase (POD) and catalase (CAT) under drought stress. According to the results, the present study may provide a candidate gene involved in the drought stress response and a theoretical basis to understand the mechanisms of ZmWRKY40 in response to abiotic stresses in maize.

There are limitations to the use of single biomarker levels, for example phosphate and tensin homology (PTEN) or vascular endothelial growth factor (VEGF), in the diagnosis of esophageal squamous cell carcinoma (ESCC). The present study therefore aimed to evaluate the clinical implications of combined detection of multiple biomarkers. The associations between PTEN and VEGF expression status, microvessel density (MVD), and the pathological characteristics of 50 patients with ESCC were determined using χ2, analysis of variance, and t-tests. The results indicated that the PTEN-positive rate was negatively correlated with ESCC histological grade (P

Cold shock proteins (CSPs) enhance acclimatization of bacteria to adverse environmental circumstances. The Escherichia coli CSP genes CspA and CspB were modified to plant-preferred codon sequences and named as SeCspA and SeCspB. Overexpression of exogenous SeCspA and SeCspB in transgenic Arabidopsis lines increased germination rates, survival rates, and increased primary root length compared to control plants under drought and salt stress. Investigation of several stress-related parameters in SeCspA and SeCspB transgenic wheat lines indicated that these lines possessed stress tolerance characteristics, including lower malondialdehyde (MDA) content, lower water loss rates, lower relative Na+ content, and higher chlorophyll content and proline content than the control wheat plants under drought and salt stresses. RNA-seq and qRT-PCR expression analysis showed that overexpression of SeCsp could enhance the expression of stress-responsive genes. The field experiments showed that the SeCspA transgenic wheat lines had great increases in the 1000-grain weight and grain yield compared to the control genotype under drought stress conditions. Significant differences in the stress indices revealed that the SeCspA transgenic wheat lines possessed significant and stable improvements in drought tolerance over the control plants. No such improvement was observed for the SeCspB transgenic lines under field conditions. Our results indicated that SeCspA conferred drought tolerance and improved physiological traits in wheat plants.

Growing evidence indicates that elongation factor 1&alpha, (EF1&alpha, ) is involved in responses to various abiotic stresses in several plant species. Soybean EF1&alpha, proteins include three structural domains: one GTP-binding domain and two oligonucleotide binding domains that are also called as domain 2 and domain 3. In this study, 10 EF1&alpha, genes were identified in the soybean genome. We predicted structures of different domains and analyzed gene locations, gene structures, phylogenetic relationships, various cis-elements, and conserved domains of soybean EF1&alpha, s. The expression patterns of 10 EF1&alpha, genes were analyzed by quantitative real-time PCR (qRT-PCR). Under drought stress, soybean EF1&alpha, genes were upregulated in varying degrees. In particular, GmEF4 was upregulated under drought and salt treatments. Compared to the drought- and salt-treated empty vector (EV)-control plants, drought- and salt-treated GmEF4-overexpressing (OE) plants had significantly delayed leaf wilting, longer root, higher biomass, higher proline (Pro) content, and lower H2O2, O2&minus, and malondialdehyde (MDA) contents. Thus, this study provides a foundation for further functional genomics research about this important family under abiotic stress.

The aim of this study was to identify a microRNA (miRNA) expression signature for predicting HCC (hepatocellular carcinoma) survival. A total of 322 HCC patients in The Cancer Genome Atlas (TCGA) database were randomly divided into training and testing set. miRNAs, associated with survival time in the training set, were identified by using univariate Cox regression analysis. The risk score was formulated based on the expression levels of these miRNAs. Then the miRNA signature was validated in testing set through Kaplan-Meier analysis and log-rank test. hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468 were identified to formulate risk score in training set and used to calculate the risk score of each patients in testing set. About 161 patients in testing set were segregated into high- and low-risk group according to the median risk score. The survival time of high-risk group was significantly shorter (p = 0.0248) than low-risk group in testing test. The target genes of five miRNAs were significantly enriched in valine, leucine, and isoleucine degradation pathway and PPAR signaling pathway. hsa-miR-1468 had an up-regulated tendency in HCC tissues compared to adjacent tumor tissues. The expression of hsa-miR-301a, hsa-miR-132, hsa-miR-212, hsa-miR-489, and hsa-miR-1468, which might be potential biomarkers to evaluate HCC patients' prognosis.

In order to explore a non-destructive monitoring technique, the use of digital photo pixels canopy cover (CC) diagnosis and prediction on maize growth and its nitrogen nutrition status. This study through maize canopy digital photo images on relationship between color index in the photo and the leaf area index (LAI), shoot dry matter weight (DM), leaf nitrogen content percentage (N%). The test conducted in the Chinese Academy of Agricultural Science from 2012 to 2013, based on Maize canopy Visual Image Analysis System developed by Visual Basic Version 6.0, analyzed the correlation of CC, color indices, LAI, DM, N% on maize varieties (Zhongdan909, ZD 909) under three nitrogen levels treatments, furthermore the indicators significantly correlated were fitted with modeling, The results showed that CC had a highly significant correlation with LAI (r = 0.93, p0.01), DM (r = 0. 94, p0.01), N% (r = 0.82, p0.01). Estimating the model of LAI, DM and N% by CC were all power function, and the equation respectively were y = 3.281 2x(0.763 9), y = 283.658 1x(0.553 6) and y = 3.064 5x(0.932 9); using independent data from modeling for model validation indicated that R2, RMSE and RE based on 1 : 1 line relationship between measured values and simulated values in the model of CC estimating LAI were 0.996, 0.035 and 1.46%; R2, RMSE and RE in the model of CC estimating DM were 0.978, 5.408 g and 2.43%; R2, RMSE and RE in the model of CC estimating N% were 0.990, 0.054 and 2.62%. In summary, the model can comparatively accurately estimate the LAI, DM and N% by CC under different nitrogen levels at maize grain filling stage, indicating that it is feasible to apply digital camera on real-time undamaged rapid monitoring and prediction for maize growth conditions and its nitrogen nutrition status. This research finding is to be verified in the field experiment, and further analyze the applicability throughout the growing period in other maize varieties and different planting density.

The winter wheat(Triticum aestivum L.)-summer maize(Zea mays L.) rotation is the main crop system in North China plain.In recent years,with continuous increase of air temperature,the double late-cropping system(late sowing for winter wheat and late harvested for summer maize) has of importance for whole-year high yield in this area.Proper scheme of light and heat in the double late-cropping system can provide high resource use efficiency(RUE) and high yields of both wheat and maize.To quantitatively analyze the yield performance and the effect of "double late" we need,two cultivars of winter wheat and two cultivars of summer maize in field experiments in Wen county and Jiaozuo of Henan province in 2006-2007 and 2007-2008 respectively.The dry matter production,grain yield,yield performance quantitative parameters,and energy(light and accumulated temperature) used efficiency were investigated in the double late-cropping system and compared with those in traditional cropping system(control).The results showed that the whole-year yield was 21 891-22 507 kg ha-1 in the double late-cropping system with 442-2 575 kg ha-1 more than that in control.In wheat cropping season,the yield of FS230 was slightly reduced with no significant difference from that of the control,but the yield of Yumai 49 significantly(P 0.05) decreased by 291-305 kg ha-1.In the maize cropping season,yield increased by 747-2 700 kg ha-1,which highly compensated the yield loss of winter wheat.In the yield performance quantitative parameters,although the mean leaf area index,spike number,and grain number per spike of winter wheat decreased in the double late-cropping system,the mean net assimilation rate,harvest index,and grain weight were significantly(P 0.05) promoted.Similarly,the mean leaf area index,harvest index,growth duration,and grain weight of maize significantly increased in the double late-cropping system.The light and temperature use efficiency were 2.22-10.86% and 0.47-11.56% higher in the double late-cropping system than in control.The results imply that the double late-cropping system has good performances on grain yield and resource use efficiency.The high whole-year yield and high production efficiency in double late-cropping system are mainly subject to the cropping season of maize,a C4 plant with high photosynthetic efficiency.Thus,based on late sowing,early-maturing wheat cultivars are suggested to be used in the double cropping system in northern China,resulting in longer grain-filling period of the following maize crop and ultimately higher yield.

Functional stay-green has been regarded as a promising characteristic to be introduced for improving rice yield potential. A functional stay-green rice “SNU-SG1” that was identified from japonica rice collections was compared with two regular high-yielding rice cultivars (HYVs) for the temporal change of leaf chlorophyll, soluble protein, and root activity, and nitrogen accumulation and remobilization during the grain-filling period. SNU-SG1 had slower decreasing rate and maintained higher concentration of chlorophyll and soluble protein in upper four leaves during the grain-filling period than HYVs “Suweon490” and “Andabyeo”, revealing a typical stay-green characteristic. Even though SNU-SG1 remobilized almost the same proportion of N accumulated before heading as HYVs to grain, it maintained much higher leaf N concentration due to the significantly higher N accumulation that is ascribable to the higher root activity sustenance during grain-filling period. The functional stay-green trait of SNU-SG1 seems to stem not only from the genetic control preventing chlorophyll degradation but also from the higher capacity to absorb N from soil due to the sustained strong root activity during grain-filling period. SNU-SG1 exhibited higher crop growth rate during late grain-filling period than HYVs, resulting in higher grain-filling percentage and non-structural carbohydrate re-accumulation in the stem at the final stage of grain filling. It is concluded that SNU-SG1 has a promising trait “functional stay-green” contributable to rice yield potential improvement through the improved grain filling.

The objective of this study was to evaluate the feasibility of using color digital image analysis and back propagation (BP) based artificial neural networks (ANN) method to estimate above ground biomass at the canopy level of winter wheat field. Digital color images of winter wheat canopies grown under six levels of nitrogen treatments were taken with a digital camera for four times during the elongation stage and at the same time wheat plants were sampled to measure above ground biomass. Canopy cover (CC) and 10 color indices were calculated from winter wheat canopy images by using image analysis program (developed in Microsoft Visual Basic). Correlation analysis was carried out to identify the relationship between CC, 10 color indices and winter wheat above ground biomass. Stepwise multiple linear regression and BP based ANN methods were used to establish the models to estimate winter wheat above ground biomass. The results showed that CC, and two color indices had a significant cor- relation with above ground biomass. CC revealed the highest correlation with winter wheat above ground biomass. Stepwise multiple linear regression model constituting CC and color indices of NDI and b, and BP based ANN model with four variables (CC, g, b and NDI) for input was constructed to estimate winter wheat above ground biomass. The validation results indicate that the model using BP based ANN method has a better performance with higher R2 (0.903) and lower RMSE (61.706) and RRMSE (18.876) in comparation with the stepwise regression model.

To explore the diagnostic value of magnifying endoscopy and human telomerase reverse transcriptase (hTERT) in identifying precancerous lesions of gastric mucosa.154 patients with upper digestive symptoms were included in the study. They were examined by the same senior doctor using magnifying endoscopy, and real-time diagnosis was made during the examination. Forceps biopsies were taken for pathological examination and were examined the expression of human telomerase reverse transcriptase mRNA (hTERT mRNA) by real-time quantitative PCR. The morphology of gastric pits under magnifying endoscopy was classified as follows: type A: round spot pits, type B: linear, type C: sparsely and thickly linear, typed D: patchy, and type E: villous.The divergence of intestinal metaplasia had significant differences implications among the gastric pit patterns from B to E under magnifying endoscopy (chi(2) = 17.58, P0.05). The more sever the intestinal metaplasia, the higher the pattern scale of the gastric pit (Pearson = 0.531, P0.05). The degree of dysplasia had a parallel relationship with the gastric pit patterns changed from C to E (chi(2) = 10.256, P0.05, Pearson = 0.549, P0.05). The expressions of hTERT mRNA of mucosa had significant differences among the gastric pit patterns B, C, D and E (F = 3.274, P0.05); If the expression of hTERT mRNA were taken as diagnostic criteria of gastric cancer, 65% of pit type E would be considered as gastric cancer which were otherwise negative by pathology.The micro-structural changes of gastric mucosa under magnifying endoscopy can reflect the severity of gastric disease, hTERT is a very important marker for diagnosis of gastric carcinoma. It is useful to predict the malignant change of gastric precancerous lesions in patients by following up high expression of hTERT mRNA combined with pit type E diagnosed by magnifying endoscopy.