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Biotic and abiotic stresses are main factors limiting crop plants yields and adaptability. Antimicrobial peptides (AMPs) play a pivotal role in plant immune responses to diverse stresses, and hence, becoming novel and essential molecules for studying plant responses to environmental harsh conditions. In this study, for the first time, overexpression of recombinant defensin NaD1gene under control of 3x 35S promoter was incorporated into tobacco plants resulting in generating NaD1 transgenic lines. Stable expression of NaD1 in transgenic tobacco lines was confirmed by RT-PCR, and next, presence of NaD1 recombinant peptide was verified by ELISA and western blot analysis in transgenic lines. In Silico bioinformatic analysis revealed that the most abundant components in Cis-regulatory elements in eleven NaD1 homologs in Nicotiana attenuate (NaDEF genes) are MYB, MYC and ABRE elements suggesting that NaD1 promoter is involved in regulation of abiotic stresses. Overexpression of the NaD1 in transgenic plants led to a significant (P ≤ 0.01) increase in the content of chlorophyll a, b, and total chlorophyll under drought stress. Correspondingly, the index of chlorophyll stability significantly increased in 3 transgenic lines. Moreover, activities of Catalase (CAT), Peroxidase (POD), Ascorbate peroxidase (APX) and S uperoxide dismutase (SOD) were significantly enhanced in response to drought stress in transgenic lines. Among three transgenic lines, line 1 showed the highest chlorophyll level and chlorophyll stability index and a high level of POD, CAT, and SOD enzyme activity under drought stress. The data together suggest that increased antioxidant activity of the enzymes might presumably lead to eliminate ROS levels and maintain the chlorophyll content and stability in response to drought stress. Therefore, the antimicrobial peptide defensin NaD1 can be considered an essential factor in regulation of plant responses to drought stress and could be used in developing transgenic lines resistant to abiotic stresses.

Lentil cultivation could be challenged by combined heat and drought stress in semi-arid regions. We used RNA-seq approach to profile transcriptome changes of Lens culinaris exposed to individual and combined heat and drought stresses. It was determined that most of the differentially expressed genes observed in response to combined stress, could not be identified by analysis of transcriptome exposed to corresponding individual stresses. Interestingly, this study results revealed that the expression of ribosome generation and protein biosynthesis and starch degradation pathways related genes were uniquely up-regulated under the combined stress. Although multiple genes related to antioxidant activity were up-regulated in response to all stresses, variation in types and expression levels of these genes under the combined stress were higher than that of individual stresses. Using this comparative approach, for the first time, we reported up-regulation of several TF, CDPK, CYP, and antioxidant genes in response to combined stress in plants.

Selection of transgenic plants by using genes encoding screenable markers of plant origin with health benefit properties, such as anthocyanin is an important aim in plant genetic engineering. In this study, Malus domestica MYB10 (MdMYB10) gene, was used for Agrobacterium tumefaciens-mediated transformation of two SBS-02 and SBS-04 sugar beet lines. The impact of different light regimes on plant tissue culture from a combination of light, dark/light and dark was investigated. The results of this study showed that the MdMYB10 gene was successfully integrated into the selected purple transgenic lines, suggesting that the expression of MdMYB10 gene in sugar beet shoots can be used as a screenable markers for transformation, possibly replacing antibiotic resistant genes. Furthermore, the results of the antibacterial activity of transgenic plants extracts showed that the total extract obtained from transgenic lines significantly (P

The receptor like kinases (RLKs) belong to the RLK/Pelle superfamily, one of the largest gene families in plants. RLKs play an important role in plant development, as well as in response to biotic and abiotic stresses. The lysine motif receptor like kinases (LysM-RLKs) are a subfamily of RLKs containing at least one lysine motif (LysM) that are involved in the perception of elicitors or pathogen-associated molecular patterns (PAMPs). In the present study, 77 putative RLKs genes and three receptor like proteins were identified in potato (Solanum tuberosum) genome, following a genome-wide search. The 77 potato RLK proteins are classified into two major phylogenetic groups based on their kinase domain amino acid sequence similarities. Out of 77 RLKs, 10 proteins had at least one LysM. Among them three RLP proteins were found in potato genome with either 2 or three tandem LysM but these lacked a cytoplasmic kinase domain. Expression analyses of a potato LysM-RLKs (StLysM-RLK05) was carried out by a Real time RT-PCR, following inoculation of potato leaves and immature tubers with late blight and common scab pathogens, respectively. The expression was significantly higher in resistant than in susceptible following S. scabies inoculation. The StLysM-RLK05 sequence was verified and it was polymorphic in scab susceptible cultivar. The present study provides an overview of the StLysM-RLKs gene family in potato genome. This information is helpful for future functional analysis of such an important protein family, in Solanaceae species.

Background and Aim: Enterococcus species are opportunistic pathogens and their pathogenicity seems to be related to the presence of a number of pathogenicity genes. Since donkey’s milk is a new non-allergenic source of nutrition, this study was performed to assess the antibiogram and detection of pathogenicity genes in some Enterococcus faecalis isolates from donkey’s milk. Materials and Method: In this experimental study, several Enterococcus faecalis strains were isolated from donkey’s milk. Resistance patterns of the isolates to 10 antibiotics including vancomycin were investigated based on CLSI protocol. Statistical comparison was made by Fisherchr('39')s exact test. Polymerase chain reaction (PCR) amplification was used to study gel E, esp, ace, as and efaA pathogenicity related genes. Results: Enterococcus faecalis isolates showed a different antibiogram pattern. Isolates were resistant to azithromycin, and erythromycin, but were susceptible to ampicillin and penicillin. Previously isolated LUB93929 and LUB93101 isolates were found to be susceptible and resistance to vancomycin, respectively. GelE, ace and efaA genes were detected in both Enterococcus faecalis isolates and also in E. faecalis in the control strains. The aggregation substance gene (as) was only amplified in LUB93101 isolate. Interestingly, esp gene was not detected in any of the isolates. Conclusion: Despite resistance to vancomycin and presence of some pathogenicity related genes in this study, E. faecalis isolates may not be human pathogens due to lack of pathogenic factors. The esp gene is crucial for biofilm formation and rise of nosocomial infections. Donkey’s milk Enterococcus faecalis isolates are not able to form biofilm and seem not to bring any problem.

Expression of strong antimicrobial peptides in plants is of great interest to combat a wide range of plant pathogens. To bring the Dermaseptin B1 (DrsB1) peptide to the intimate contact of the plant pathogens cell wall surface, the DrsB1 encoding sequence was fused to the C-terminal part of the two copies of the chitin-binding domain (CBD) of the Avr4 effector protein and used for Agrobacterium rhizogenes-mediated transformation. The expression of the recombinant protein in the tobacco hairy roots (HRs) was confirmed by molecular analysis. Antimicrobial activity analysis of the recombinant protein purified from the transgenic HRs showed that the (CBD)2-DrsB1 recombinant protein had a significant (p

Background: Antimicrobial peptides are one of the vital components of innate immunity in plants and animals. The identification and introduction of novel and effective peptide molecules to plants is a cost-effective way both to improve the resistance of crop plant species to pathogens, and to produce peptides for pharmaceutical applications by using recombinant DNA technology. Material and Methods: An expression construct containing the omiganan (MBI-226) antimicrobial gene sequence was cloned and used for tobacco and potato Agrobacterium tumefaciens-mediated transformation. Following tissue culture, Polymerase chain reaction analysis (PCR) confirmed that some kanamycin resistant plants are transgenic. A number of transgenic plants, along with a non-transgenic control, were selected. Total protein was extracted from the transgenic plants, and the non-transgenic control, and was used for antimicrobial activity assay against some human pathogens, including; Escherchia coli, Staphylococcus epidermis, Pseudomonas aeruginosa, Salmonella typh, Staphylococcus aureus, Bacillus cereus, Candida albicans using the disc diffusion method. Results: Total protein extract from transgenic plants was significantly (P0.05) on human gram-positive pathogenic bacteria. Conclusion: The total protein from the omiganan-expressing peptide had a strong antibacterial activity against some human bacterial pathogens. By expression and purification of the omiganan peptide, the peptide could be used as an antibiotic to destroy pathogenic bacteria. This approach could open an opportunity to produce antibacterial peptides in plants for pharmaceutical applications.

Breeding new rice varieties with high Eating and Cooking Quality (ECQ) characteristics is an important goal in rice breeding programs. To this end, 242 Recombinant Inbred Lines (RILs) of two populations derived from Alikazemi/IR67017-180-2-1-2 and Alikazemi/Saleh crosses were evaluated in two environments. The main and epistatic QTLs and QTL × Environment (Q × E) interactions were analyzed using the Mixed-Model-based Composite Interval Mapping method. A total of 17 main QTLs with additive effects were mapped on 6 rice chromosomes, including 6 QTLs for Amylose Content, 5 QTLs for Gelatinization Temperature and 6 QTLs for Gel Consistency. Seven QTLs were found on chromosome 6 associated with a common RM4128 marker (close to the Alk locus) influencing the ECQ characteristics with favorable alleles from the common female parent. Five QTL clusters were identified on chromosome 6, 7, 8, and 9, suggesting that the co-located QTLs with pleiotropic effects may control ECQ traits. A major QTL cluster was found for AC and GC between RM4128 and RM549 markers close to the Alk locus on chromosome 6, which is in the vicinity of another QTL located in RM587-RM4128 interval. 13 QTL pairs were identified to have a significant epistatic, Additive × Additive effects involved in controlling ECQ traits. A small phenotypic variation was found for the epistatic QTLs and Q × E interactions, suggesting the complexity of ECQ inheritance traits in rice. Further comprehensive studies and validation of the detected QTLs could be useful for marker-assisted selection to improve grain quality in rice.

Antimicrobial peptides have been long known to confer resistance to plant pathogens. In this study, new recombinant peptides constructed from a dermaseptin B1 (DrsB1) peptide fused to a chitin-binding domain (CBD) from Avr4 protein, were used for Agrobacterium tumefaciens-mediated transformation of tobacco plants. Polymerase chain reaction (PCR), semi‐quantitative RT‐PCR, and western blotting analysis demonstrated the incorporation and expression of transgenes in tobacco genome and transgenic plants, respectively. In vitro experiments with recombinant peptides extracted from transgenic plants demonstrated a significant (P

Extreme temperature is one of the serious threats to crop production in present and future scenarios of global climate changes. Lentil (Lens culinaris) is an important crop, and there is a serious lack of genetic information regarding environmental and temperature stresses responses. This study is the first report of evaluation of key genes and molecular mechanisms related to temperature stresses in lentil using the RNA sequencing technique. De novo transcriptome assembly created 44,673 contigs and differential gene expression analysis revealed 7494 differentially expressed genes between the temperature stresses and control group. Basic annotation of generated transcriptome assembly in our study led to the identification of 2765 novel transcripts that have not been identified yet in lentil genome draft v1.2. In addition, several unigenes involved in mechanisms of temperature sensing, calcium and hormone signaling and DNA-binding transcription factor activity were identified. Also, common mechanisms in response to temperature stresses, including the proline biosynthesis, the photosynthetic light reactions balancing, chaperone activity and circadian rhythms, are determined by the hub genes through the protein-protein interaction networks analysis. Deciphering the mechanisms of extreme temperature tolerance would be a new way for developing crops with enhanced plasticity against climate change. In general, this study has identified set of mechanisms and various genes related to cold and heat stresses which will be useful in better understanding of the lentil's reaction to temperature stresses.

Structural mutations providing herbicide resistance may cause a modification of the three dimensional structure of a protein which will lead to a decrease in the herbicide efficacy. Wild oat (Avena ludoviciana Durieu.) is an increasingly disruptive weed in areas of intensive cereal production, thus the aim of this research was to identify mutations conferring resistance to ACCase-inhibitor herbicides at greenhouse, laboratory and in silico scales. Among the selected biotypes, No. 3 in the position 1781 (Ile1781-Leu) and No. 14 in the position 2041 (Ile2041-Asn), showed resistance to ACCase-inhibitor. The above mutations were confirmed using the specific primers and PCR-based methods. Analysis of molecular docking indicated that residues of Trp1948 and Pro2001 are important in the binding site and showed remarkable variation in the mutation types. Using molecular dynamic simulation analysis, we demonstrated that mutation types changed the conformation of the enzyme. These changes resulted in compressed conformation in the active site, which limited the availability of binding herbicide-enzyme. In present, no crystallography molecular structure and modeling reported on the ACCase of plants and this study investigated interactions of clodinafop propargyl and ACCase CT domain in A. ludoviciana by modeling, docking and simulations for the first time. Totally, bioinformatics analysis as well as PCR-based method confirmed that herbicide resistance conferred by nucleotide mutations in the gene sequence.

Opium poppy (Papaver somniferum L.) remains the only commercial source for several pharmaceutical alkaloids. In present study, opium poppy plants were genetically manipulated via VIGS technique using pTRV2-BBE (to silencing of BBE1 gene), pTRV2-COM (to simultaneous silencing of T6ODM and CODM genes) and pTRV2-BBE-COM (to simultaneous silencing of T6ODM, CODM and BBE1 genes) constructs. Also, via Agrobacterium-mediated transient expression technique, poppy plants were genetically manipulated using ACS (to simultaneous silencing of T6ODM, CODM and BBE1) and ACS-4ꞌOMT2 (to simultaneous silencing of T6ODM, CODM and BBE1 and over-expression of 4ꞌOMT2) constructs. HPLC analysis showed lower sanguinarine and noscapine levels and elevated levels of morphine in plants infiltrated with pTRV2-BBE construct. In plants infiltrated with pTRV2-COM construct, reduction in the morphine and codeine content and a substantial increase in accumulation of thebaine and papaverine were observed. A substantial increase in the accumulation of thebaine and papaverine and lower levels of morphine, codeine, sanguinarine and noscapine were observed in plants infiltrated with pTRV2-BBE-COM and ACS constructs. Plants infiltrated with ACS-4ꞌOMT2 showed lower levels of codeine, sanguinarine and noscapine and elevated levels of morphine, thebaine and papaverine. Although, previous studies reported the role of our selected genes in benzylisoquinoline alkaloids (BIAs) biosynthetic pathway, but we simultaneously engineered these genes to alter the levels of specific BIAs and take advantage of all genes at the same time. For the first time, we showed different pattern in BIAs accumulation in simultaneous gene manipulation compared with single gene manipulation in previous reports, especially for higher levels of thebaine (about 1550%) and papaverine (about 155%). We also determined potential role of BBE1 gene in noscapine biosynthesis. This is the first report of simultaneous silencing and over-expression of biosynthetic genes in opium poppy and our finding could establish vast potential for metabolic engineering in opium poppy.

Background: Root hair culture is a valuable system to produce recombinant proteins in planta. Antimicrobial peptides (AMPs) are vital parts of the innate immune response found in almost all forms of life. Precise target activity and limited toxicity towards mammalian cells make them suitable candidate molecules to combat evolving drug-resistant microorganisms. The aim of the present study was to produce a Dermaseptin B1 recombinant antimicrobial peptide in Nicotiana tabacum root hair and assess the antibacterial activity of the protein extract from transgenic root hairs. Materials and Methods: A Dermaseptin B1 encoding gene sequence was C-terminally fused to a Chitin Binding Domain (CBD) encoding sequence and cloned in a plant binary vector used for Agrobacterium rhizogenes-mediated transformation to generate root hairs in tobacco. Transgenic root hairs were produced, and protein extracts were used to assess antimicrobial activity against a number of microbes. Results: PCR and RT-PCR analysis confirmed the integration of the Dermaseptin B1 gene in a root hair cell genome and the presence of Dermaseptin B1 mRNA transcripts, respectively. Recombinant protein had a significant (P

Starch, a very compact form of glucose units, is the most abundant form of storage polyglucan in nature. The starch synthesis pathway is among the central biochemical pathways, however, our understanding of this important pathway regarding genetic elements controlling this pathway, is still insufficient. Starch biosynthesis requires the action of several enzymes. Soluble starch synthases (SSs) are a group of key players in starch biosynthesis which have proven their impact on different aspects of the starch biosynthesis and functionalities. These enzymes have been studied in different plant species and organs in detail, however, there seem to be key differences among species regarding their contributions to the starch synthesis. In this review, we consider an update on various SSs with an emphasis on potato SSs as a model for storage organs. The genetics and regulatory mechanisms of potato starch synthases will be highlighted. Different aspects of various isoforms of SSs are also discussed., Highlights • We have shown that transgenic plants with modified starches has been generated by manipulation of various SSs. • A detailed characterization of the biosynthetic machinery is required to understand the effects of inhibiting any particular SSs. • A comparison is made between the predicted 3D structure of potato SSs with those of rice, barley and glycogen synthases. • We have pointed out the similarities and differences between different potato SSs. • We have managed to summarize most of the finding regarding in planta modification of different SSs.

Dermaseptin B1 (DrsB1), an antimicrobial cationic 31 amino acid peptide, is produced by Phyllomedusa bicolor. In an attempt to enhance the antimicrobial efficacy of DrsB1, the DrsB1 encoding 93 bp sequence was either fused to the N or C terminus of sequence encoding chitin‐binding domain (CBD) of Avr4 gene from Cladosporium fulvum. Tobacco leaf disk explants were inoculated with Agrobacterium rhizogenes harboring pGSA/CBD‐DrsB1 and pGSA/DrsB1‐CBD expression vectors to produce hairy roots (HRs). Polymerase chain reaction (PCR) was employed to screen putative transgenic tobacco lines. Semi‐quantitative RT‐PCR and western blotting analysis indicated that the expression of recombinant genes were significantly higher, and recombinant proteins were produced in transgenic HRs. The recombinant proteins were extracted from the tobacco HRs and used against Pectobacterium carotovorum, Agrobacterium tumefaciens, Ralstonia solanacearum, and Xanthomonas campestris pathogenic bacteria and Alternaria alternata and Pythium sp. fungi. Two recombinant proteins had a statistically significant (p, Harnessing a chitin‐binding domain from Cladosporium fulvum Avr4 effector protein as fusion to the Dermaseptin B1 peptide enhances the antimicrobial activity of the peptide toward microbial pathogens.

The receptor like kinases (RLKs) belong to the RLK/Pelle superfamily, one of the largest gene families in plants. RLKs play an important role in plant development, as well as in response to biotic and abiotic stresses. The lysine motif receptor like kinases (LysM-RLKs) are a subfamily of RLKs containing at least one lysine motif (LysM) that are involved in the perception of elicitors or pathogen-associated molecular patterns (PAMPs). In the present study, 77 putative RLKs genes and three receptor like proteins were identified in potato (Solanum tuberosum) genome, following a genome-wide search. The 77 potato RLK proteins are classified into two major phylogenetic groups based on their kinase domain amino acid sequence similarities. Out of 77 RLKs, 10 proteins had at least one LysM. Among them three RLP proteins were found in potato genome with either 2 or three tandem LysM but these lacked a cytoplasmic kinase domain. Expression analyses of a potato LysM-RLKs (StLysM-RLK05) was carried out by a Real time RT-PCR, following inoculation of potato leaves and immature tubers with late blight and common scab pathogens, respectively. The expression was significantly higher in resistant than in susceptible following S. scabies inoculation. The StLysM-RLK05 sequence was verified and it was polymorphic in scab susceptible cultivar. The present study provides an overview of the StLysM-RLKs gene family in potato genome. This information is helpful for future functional analysis of such an important protein family, in Solanaceae species.

Salt stress is one of the major adverse environmental factors limiting crop productivity. Considering Iran as one of the bread wheat origins, we sequenced root transcriptome of an Iranian salt tolerant cultivar, Arg, under salt stress to extend our knowledge of the molecular basis of salinity tolerance in Triticum aestivum. RNA sequencing resulted in more than 113 million reads and about 104013 genes were obtained, among which 26171 novel transcripts were identified. A comparison of abundances showed that 5128 genes were differentially expressed due to salt stress. The differentially expressed genes (DEGs) were annotated with Gene Ontology terms, and the key pathways were identified using Kyoto Encyclopedia of Gene and Genomes (KEGG) pathway mapping. The DEGs could be classified into 227 KEGG pathways among which transporters, phenylpropanoid biosynthesis, transcription factors, glycosyltransferases, glutathione metabolism and plant hormone signal transduction represented the most significant pathways. Furthermore, the expression pattern of nine genes involved in salt stress response was compared between the salt tolerant (Arg) and susceptible (Moghan3) cultivars. A panel of novel genes and transcripts is found in this research to be differentially expressed under salinity in Arg cultivar and a model is proposed for salt stress response in this salt tolerant cultivar of wheat employing the DEGs. The achieved results can be beneficial for better understanding and improvement of salt tolerance in wheat.

Fusarium head blight (FHB) is a destructive disease affecting cereal crops globally due to mycotoxin contamination of grains that reduce yield and quality. Among hundreds of QTLs identified for resistance, the QTL-Fhb1 is of significant interest even today, for its major contribution to FHB resistance. Previously, QTL-Fhb1 dissection based on a combined metabolo-genomics approach, identified a few potential resistance genes, including a NAC like transcription factor for FHB resistance. Sequencing and phylogenetic analysis confirmed NAC to be the wheat TaNAC032. Also, the quantitative RT-PCR studies revealed a greater induced expression of TaNAC032 in resistant NIL in comparison to susceptible NIL upon Fusarium graminearum (Fg) infection. The virus-induced gene silencing (VIGS) based functional validation of TaNAC032 in resistant NIL confirmed increased disease severity and fungal biomass. Metabolic profiling revealed low abundances of resistance-related (RR) metabolites in TaNAC032 silenced NIL-R compared to non-silenced. Silenced plants showed decreased transcript abundances of RR metabolite biosynthetic genes associated with a reduction in total lignin content in rachis, confirming the regulatory role of TaNAC032 in wheat in response to Fg infection. If TaNA032 is mutated in an FHB susceptible cultivar, it can be edited to enhance FHB resistance.

Background : The utilization of donkey’s milk is increasing with regard to nutritional values and non-allergenic proteins. Donkey’s milk microbiota, especially lactic acid bacteria (LAB) has not yet been fully identified. This study was conducted to identify and isolate LAB with probiotic properties. Materials and Methods: Specific culture-dependent techniques and standard microbiology methods were used to identify LAB. 250 isolates were randomly picked from different donkey’s milk samples different farms in Alashtar, north of Lorestan province, Iran. Gram-staining, catalase reaction, motility test, growth at different temperatures, pH 9.6 and in presence of 6.5% NaCl as well as the ability to ferment different sugars, sodium hippurate hydrolysis and light microscope analysis were investigated. Results: Out of 250 isolates, 20 isolates were gram-positive, catalase-negative and cocci form. Enterococcus and Streptoccus genera were dominant LAB in donkey’s milk. Entreococcus faecalis (55%) and Streptococcus devriesei (45%) were among the predominant species. The results of this experiment, for the first time, reported the occurrence of Streptococcus devriesei in donkey’s milk in Iran. Conclusion: Despite high lysozyme concentration, donkey’s milk rich in probiotic LAB can be used to feed infants with allergy to cow’s milk proteins. Both Entreococcus and Streptococcus bacteria produce different types of bacteriocins which are effective against a wide range of different type of infections. Occurrence of Streptococcus devriesei in donkey,s milk may provide new research field in Iran.

Due to its high productivity and sucrose content, sugarcane (Saccharum officinarum) is becoming the source of high-value bioproducts. Expression of bacterial extracellular polysaccharide genes in non-biopolymer accumulating plants is an excellent resource for production of added-value products. To this end, an expression cassette containing a full-length glucosyltransferase (gtfI) gene from Streptococcus downei driven by a CaMV promoter was expressed in a commercial sugarcane cultivar (CP48-103) using a biolistic approach. Copy number was assessed for a number of selected transgenic sugarcane lines by DNA blot analysis, where it was corroborated that each transgenic line contained at least two gtfI copies. The southern blot analysis of gtfI-expressing lines showed that the number of integrated copies ranged from two to four. The expression of gtfI in transgenic sugarcane plants was confirmed by mRNA blot analysis and qRT-PCR analysis. The expression of gtfI in transgenic sugarcane plants resulted in an approximate 30% reduction in sucrose accumulation, suggesting that mutansucrase actively converted sucrose to mutan polymer. In internodal stalk tissues, mutan polymer accumulated up to 55.9 mg/g FW, which apparent through glucan staining. The levels of glucose and fructose increased nearly by twofold, suggesting that mutansucrase may also have hydrolyzing activity.

An antibacterial peptide-encoding gene from alfalfa seeds, alfAFP, was fused to the C-terminal part of chitin-binding domain (CBD) of the rice chitinase-encoding gene (CBD-alfAFP) and introduced to tobacco by Agrobacterium-mediated transformation. Polymerase chain reaction (PCR) technique was used to confirm the integration of the recombinant CBD-alfAFP encoding gene in transgenic tobacco plants. A number of transgenic lines and a non-transgenic control plant were selected for further molecular analyses. The result of analyzing the transgenic plants by semi-quantitative RT-PCR showed that the recombinant gene is expressed in transgenic plants and there is a difference between the transgenic plants in terms of the level of CBD-alfAFP expression. The total protein was extracted from a few selected transgenic plants and used to evaluate the antibacterial/antifungal of recombinant protein activity against some important plant and human pathogens. The results of this experiment showed that the total protein extract obtained from transgenic lines significantly (P

Background Contamination of food and agricultural crops by Fusarium species is a major concern of food spoilage and a potential public health hazard. In the present study, natural contamination of maize and wheat samples from main cultivation areas of Iran by Fusarium species belonging to the Giberella fujikuroi species complex was evaluated, with special attention to the ability of the isolates to produce fumonisin B1 (FB1 ). Results A total of 55 Fusarium isolates were obtained from 27/32 maize samples (84.4%) and 11/15 wheat samples (73.3%). They were identified as F. verticillioides (47.3%), F. proliferatum (47.3%), F. fujikuroi (1.8%), F. nygamai (1.8%) and F. redolens (1.8%) by sequence analysis of translation elongation factor 1-α (TEF1-α). Twenty-two of 55 Fusarium isolates belonging to F. proliferatum (23.6%), F. verticillioides (14.5%) and F. fujikuroi (1.8%) produced FB1 in the concentration range 230.4-9565.0 µg mL(-1) . The dendrogram resulting from the TEF1-α profile showed that the genotypes were divided into clusters I, II and III, of which cluster III contained only F. redolens, its first report from Iran. Conclusion On the basis of in vitro FB1 biosynthesis of the analyzed strains, the high degree of contamination of maize and wheat with Fusarium strains reported here should be considered as a potential public health threat, because a meaningful number of the isolates were found to produce hazardous levels of carcinogenic FB1 .

Pomegranate (Punica granatum L.) is one of the oldest and important horticultural plants in Iran. Pomegranate fruits are an important source of secondary metabolites such as phenolic compounds, tannins, colors and alkaloids. Anthocyanin accumulation in plant organs is associated with gene expression in anthocyanin biosynthesis pathway. Regulation of anthocyanin biosynthesis expression is controlled by a number of transcription factors including MYB, basic helix–loop–helix (bHLH) and WD-repeat protein (WD-Repeat) proteins. In order to study the expression level of some transcription factors/genes and their role in pomegranate skin color, real time PCR analysis was used to assess the expression patterns among different pomegranate genotypes. Results of this study showed that white and green skin genotypes had the highest AN1 (bHLH) expression, whereas bright red and black skin genotypes accumulated the lowest AN1 transcript level. Furthermore, green and bright red genotypes showed the highest and the lowest expression level with regard to AN2 (MYB) transcription factor, respectively. The DFR gene expression in samples with black skin was the highest while in white skin samples the lowest expression of this gene was shown. This result indicates the influence of WD40 transcription factor on DFR structural gene and its effective role on synthesis of skin color. With regard to expression of three transcription factors in all genotypes, it was evident that MYB–bHLH–WD40 complex confers the skin color in pomegranate. Total anthocyanin content measurement showed a positive correlation between the level of DFR gene expression and accumulation of anthocyaninsin different genotypes.

Weeds are serious problem in crop production and wild oat is a grass weed of economic and agronomic significance. We need to extend our basic knowledge of weeds especially in molecular genetics and gene expression. For study of gene expression by semi-quantitative and quantitative PCR, it is recommended that normalization of reference genes be carried out in order to select the most stable reference gene for a precise gene expression study. The purpose of this research was evaluation of four reference genes in response to treated and untreated (control) by herbicide in two tissues (stem and leaf) of non-target site resistance wild oat (A. ludoviciana). Four candidate reference genes including Actin, Ef1α (elongation factor 1 alpha), GAPDH (glyceraldehyde 3-phosphate dehydrogenase) and TBP (TATA-box-binding protein) were used to determine stable reference gene exposed to the herbicide using the statistical methods of NormFinder, BestKeeper and delta-Ct. NormFinder indicated that TBP and Actin genes are the best combination of two genes for normalizing calculations (with a combined gene stability value of 0.012) for qPCR analysis under herbicide stress in different tissues of non-target site resistance wild oat. Based on the statistical results, the Ef1α gene was identified as the unstable reference gene. Totally, according to results of this study, TBP gene is the most stable reference gene and therefore, this gene can be used as a reference gene for future studies of quantitative PCR analysis of herbicide stress-responsive gene expression in wild oat and potentially in other grass weed species.

Main conclusion - Expression of amylosucrase in potato resulted in larger starch granules with rough surfaces and novel physico-chemical properties, including improved freeze–thaw stability, higher end viscosity, and better enzymatic digestibility. Starch is a very important carbohydrate in many food and non-food applications. In planta modification of starch by genetic engineering has significant economic and environmental benefits as it makes the chemical or physical post-harvest modification obsolete. An amylosucrase from Neisseria polysaccharea fused to a starch-binding domain (SBD) was introduced in two potato genetic backgrounds to synthesize starch granules with altered composition, and thereby to broaden starch applications. Expression of SBD–amylosucrase fusion protein in the amylose-containing potato resulted in starch granules with a rough surface, a twofold increase in median granule size, and altered physico-chemical properties including improved freeze–thaw stability, higher end viscosity, and better enzymatic digestibility. These effects are possibly a result of the physical interaction between amylosucrase and starch granules. The modified larger starches not only have great benefit to the potato starch industry by reducing losses during starch isolation, but also have an advantage in many food applications such as frozen food due to its extremely high freeze–thaw stability.

To identify miRNAs and assess the expression of genes involved in drought stress tolerance, leaf and root ESTs were analyzed in barley. To this end, the EGassembler bioinformatics service and IDEG6 were used for the pre-processing and identify differentially expressed genes among EST libraries, respectively. Furthermore, root contigs were analyzed by C-mii software for miRNAs identification. The expression profile of two drought tolerance candidate genes was studied, using Real time-PCR in a 2 (Nimruz and Spontaneum) × 2 (control and 50% FC) factorial experiment in a completely randomized design with 3 replications. Results of this study showed that N-butyl-N-methylpiperidinium (Pip1;4) and a non-specific lipid transport protein (nsLTP) were found to express differently under drought stress. The expression level of barley HvPip1;4 (HvPiP1;4) and non-specific lipid transport (HvnsLTP) genes increased by 95.98 and 54.53 fold after 72 h of drought stress, respectively. There was a significant difference (P

The original version of this article unfortunately contained a mistake in the unit “μg/l”. The unit “μg/l” should be corrected to “μg/ml” throughout the paper.

Starch is used in many industrial applications, but often requires chemical derivatization to enhance its properties before use. In particular, the stability of starch polymers in solution is improved by acetylation. A drawback of this treatment is the use of pollutant chemicals. A biological alternative to chemical derivatization was investigated by the expression of an amyloplast-targeted Escherichia coli maltose acetyltransferase (MAT) gene in tubers of wild-type (Kardal) and mutant amylose-free (amf) potato plants. MAT was expressed as such, or fused to the N- or C-terminus of a non-catalytic starch-binding domain (SBD) to target the starch granule. Starch granules derived from transgenic plants were found to contain acetyl groups, although their content was low, opening up an avenue to move away from the post-harvest chemical derivatization of starch. MAT inside starch granules was found to be active post-harvest when supplied with acetyl-coenzyme A and glucose or maltose, but it did not acetylate starch polymers in vitro. Starch granules from transformants in which MAT alone was expressed also showed MAT activity, indicating that MAT is accumulated in starch granules, and has affinity for starch by itself. Furthermore, starch granule morphology was altered, and fusion proteins containing MAT and SBD seemed to have a higher affinity for starch granules than two appended SBDs. These results are discussed against the background of the quaternary structure of MAT.

It has been shown previously that mutan can be co-synthesized with starch when a truncated mutansucrase (GtfICAT) is directed to potato tuber amyloplasts. The mutan seemed to adhere to the isolated starch granules, but it was not incorporated in the starch granules. In this study, GtfICAT was fused to the N- or C-terminus of a starch-binding domain (SBD). These constructs were introduced into two genetically different potato backgrounds (cv. Kardal and amf), in order to bring GtfICAT in more intimate contact with growing starch granules, and to facilitate the incorporation of mutan polymers in starch. Fusion proteins of the appropriate size were evidenced in starch granules, particularly in the amf background. The starches from the various GtfICAT/SBD transformants seemed to contain less mutan than those from transformants with GtfICAT alone, suggesting that the appended SBD might inhibit the activity of GtfICAT in the engineered fusion proteins. Scanning electron microscopy showed that expression of SBD-GtfICAT resulted in alterations of granule morphology in both genetic backgrounds. Surprisingly, the amf starches containing SBD-GtfICAT had a spongeous appearance, i.e., the granule surface contained many small holes and grooves, suggesting that this fusion protein can interfere with the lateral interactions of amylopectin sidechains. No differences in physico-chemical properties of the transgenic starches were observed. Our results show that expression of granule-bound and "soluble" GtfICAT can affect starch biosynthesis differently.

The Escherichia coli glycogen branching enzyme (GLGB) was fused to either the C- or N-terminus of a starch-binding domain (SBD) and expressed in two potato genetic backgrounds: the amylose-free mutant (amf) and an amylose-containing line (Kardal). Regardless of background or construct used, a large amount of GLGB/SBD fusion protein was accumulated inside the starch granules, however, without an increase in branching. The presence of GLGB/SBD fusion proteins resulted in altered morphology of the starch granules in both genetic backgrounds. In the amf genetic background, the starch granules showed both amalgamated granules and porous starch granules, whereas in Kardal background, the starch granules showed an irregular rough surface. The altered starch granules in both amf and Kardal backgrounds were visible from the initial stage of potato tuber development. High-throughput transcriptomic analysis showed that expression of GLGB/SBD fusion protein in potato tubers did not affect the expression level of most genes directly involved in the starch biosynthesis except for the up-regulation of a beta-amylase gene in Kardal background. The beta-amylase protein could be responsible for the degradation of the extra branches potentially introduced by GLGB.

Starch exists typically as semicrystalline granules of varying size. Granule size plays an important role for many industrial starch applications. Microbial non-catalytic starch binding domains (SBD) exhibit an affinity for starch granules on their own. Three different constructs were introduced in the amylose-free potato cultivar (Solanum tuberosum L. cv. amf) to investigate whether it is possible to produce smaller starch granules by an engineered, high-affinity, tandem-repeats of a family 20 starch-binding domain (SBD3, SBD4 and SBD5). A significant reduction in the size of starch granule was achieved in transgenic potato plants. Furthermore, it was shown that the SBDn expression can affect physical processes underlying granule assembly and the poorly understood granule formation. Expression of multiple linked SBDs resulted in amalgamated starch granules that consisted of many smaller granules. No significant alterations were observed with regard to rheological properties of starch granules.

This study investigates whether it is possible to produce an amylose-free potato starch by displacing the amylose enzyme, granule-bound starch synthase I (GBSSI), from the starch granule by engineered, high-affinity, multiple-repeat family 20 starch-binding domains (SBD2, SBD3, SBD4, and SBD5). The constructs were introduced in the amylose-containing potato cultivar (cv. Kardal), and the starches of the resulting transformants were compared with those of SBD2-expressing amylose-free (amf) potato clones. It is shown that a correctly sized protein accumulated in the starch granules of the various transformants. The amount of SBD accumulated in starch increased progressively from SBD to SBD3; however, it seemed as if less SBD4 and SBD5 was accumulated. A reduction in amylose content was not achieved in any of the transformants. However, it is shown that SBDn expression can affect physical processes underlying granule assembly, in both genetic potato backgrounds, without altering the primary structure of the constituent starch polymers and the granule melting temperature. Granule size distribution of the starches obtained from transgenic Kardal plants were similar to those from untransformed controls, irrespective of the amount of SBDn accumulated. In the amf background, granule size is severely affected. In both the Kardal and amf background, apparently normal oval-shaped starch granules were composed of multiple smaller ones, as evidenced from the many "Maltese crosses" within these granules. The results are discussed in terms of different binding modes of SBD.

Starch is the major form in which carbohydrates are stored and is present in almost all plant organs at one or another time during development. Storage starch is formed in amyloplasts as dense granules ranging in size from 1 to over 100 µ M. They are composed of an essential linear glucose polymer and a branched glucose polymer termed amylose and amylopectin respectively (Ball et al 1998). Knowledge about starch biosynthesis is required to be able to modify starches for industrial or food uses. This knowledge has been acquired by studies in a broad range of plants using both mutants and reverse genetic approaches. In this way the function and impact of a number of the essential genes in the starch biosynthetic pathway has been assessed.