مجله پژوهش های سلولی مولکولی (زیست شناسی ایران)
سال سی و سوم شماره 3 (پاییز 1399)

Yaghouti grape of Sistan is an important fruit in Iran. Therefore, it is necessary some studies to evaluate different aspects related to early ripening in grape. This fruit can be harvested since first week of June. In this study, the genes related to signal transduction in early ripening were investigated, firstly; then two genes, MYBA and STE20, and GAPDH (as reference genes) were selected to more study. The expression of these genes were evaluated in different phenological growth stages and different early and late ripening genotypes of Sistan grape. The results indicated that expression of STE20 has been up-regulated highly in late-ripened genotypes (Fakhri and Cheshm-Gavi) during ripening stage. Also, there was significant difference between ripening and berry filling phenological growth stages as expression of STE20. On the other hand, this gene was down-regulated in early ripened Red-Yaghouti and White-Yaghouti genotypes. Also, the results indicated that expression of MYBA has up-regulated in early ripened Red-Yaghouti genotype of berry filling stage, while the expression of this gene was increased significantly in the late-ripened Chesm-Gavi genotype of ripening stage.

Among the various types of lipid phases, the bilayer structure is of particular importance in understanding the processes associated with cell membranes such as lipid membrane fusion. Hence, the research in modeling of L_α lipid phase has been a significant part of the simulation of bio-macromolecules. In this study, we have exploited the systematic coarse-graining approaches for modeling of the 1,2- dioleoylphosphatidylethanolamine (DOPE) lipid molecule. The implicit solvent coarse-grained model of the lipid molecule is composed of 14 beads so that the potential energy of the system consists terms of bonded, non-bonded, and electrostatic. Constructing the Coarse-grained model was accomplished based on the atomistic simulation of lipid molecules with the water content of 45 %wt using the methods of iterative Boltzmann inversion and inverse Monte Carlo. Although proper convergence in the bond and angle distribution functions was achieved at the end of iterative Boltzmann inversion procedure, the exact convergence in the torsion angle distribution functions and the radial distribution functions was obtained at the end of the Monte Carlo process. Using the obtained results, the lamellar L_α lipid phase was obtained in less than 10 nanoseconds. In addition, the coarse-grained potentials are capable of modeling the lipid multilayer fusion and the intermediate structure of lipidic particles.

Stevia rebaudiana Bertoni is from the dark Composite perennial plant, herbaceous and pollinator. Due to the being below seed germination perecentage and heterogenous multiplication of plants from seed in terms of sweetness micropropagation of this plant with use of tissue culture methods in order to replicate mass is desirable. In this study, the performance of two explant end bud and node using three treatments the concentration of the medium MS and different levels of activated charcoal and hormones BAP and Kn in two experiment compared and reviewed. So that in the first experiment the effect of active charcoal and concentration of culture media MS and in the second experiment use separate concentrations (at 0,0/5,1 and 1/5mgr/l) of hormones BAP and Kn in three repeat was implemented. Results showed the highest increase traits in the cultivation of end buds at full concentration seen of culture medium MS with to 1/5gr/l activated charcoal as absorber substance phenols. Use concentration 1/5 mgr/l of hormones BAP and Kn showed an increase in micropropagation efficiency of both explants. Performance comparison hormones BAP and Kn using 1/5 mgr/l BAP in the cultivation of the end buds showed the most characteristics of shoot length, number of nodes and the number of lateral stems.

Plant cell cultures are potential source of valuable secondary metabolites such as antioxidant compounds, flavors and fragrances. This study was designed to improve antioxidant production and evaluation the effect of salicylic acid on antioxidant activity in cell suspension culture of Lavandula angostifolia. Cell suspensions of Lavandula angostifolia were established and maintained in MS medium, supplemented with 2mg/l NAA and 4mg/l BAP. Salicylic acid was added to the medium at concentrations of 3,6,12 and 18 mg/l in stationary phase. The antioxidant activity , phenolics and flavonoids were evaluated 48 and 72 h after salicylic acid treatment. As a result the highest free radical scavenging and higher reducing power activity ( respectively 107µg/ml,4.865 µM/ASA) , The highest value of superoxide anion scavenging activity (74.205%) as well as the highest value of total phenolics (814.23 mgGA/gdw) and flavonoids (4.865mgQE/gdw865/4) were observed 72h after treatment with 12mg/L salicylic acid. Over all treatment with12mg/L salicylic acid for 72 h was better in order to antioxidant activity and compounds with recognized antioxidant properties.

Trehalose is the alpha, alpha-1,1-linked glucose disaccharide which plays pivotal roles in plants growth, development and resistance to stress. The NADPH-dependent thioredoxin reductase C (NTRC) acts as redox regulatory factor and involved in different chloroplastic processes. The aim of present study was to gain further insight into the effect of trehalose on plant antioxidant system activity. For this purpose, the seeds of Arabidopsis thaliana (WT) and ntrc mutant plants (as sensitive plants to stress) were grown on MS medium with or without 100 mM sucrose and/or trehalose for 14 days. The results showed that trehalose treatment induced peroxidase, ascorbate peroxidase and polyphenol oxidase in both mutant lines and WT seedlings, compared to control and sucrose treatment. Meanwhile these enzyme activities were higher in WT seedlings than that of ntrc mutants. Trehalose treatment decreased hydrogen peroxide and malon dialdehyde content in WT seedlings but increased phenol and anthocyanin content, compared to control. Also, the amount of hydrogen peroxide in WT seedlings was lower than mutant seedlings by trehalose feeding. The results revealed that trehalose eliminates reactive oxygen species by inducing plant antioxidant system. The obtained data can be useful to understand the role of trehalose in plant stress resistance.

The beauty of the gerbera flower depends on the lifespan of its petals. The lifespan of the petals depends on preserving the relative water content and the metabolic activity of the petals cells. The flower producers use compounds that protect and enhance the metabolism of the cells, as well as prevent the invasion of bacterial pathogens and the ability to maintain the water's potential for petals tissues. The present study was conducted to determine the lifespan and metabolic activities of the petals tissues under thyme essence and salicylic acid effects. Treatments were different concentrations of thyme essence (0, 150, 300, 600 μl L-1) and salicylic acid (0, 500, 1000, 2000 μM L-1) and their simultaneous use in aqueous medium. The treatments were sorted in the factorial experiment (4×4) on a randomized complete block design with three replications in laboratory conditions. The variables were lifespan, relative water content, activity of enzymes (phenylalanine ammonia lyase, peroxidase and catalase), malondialdehyde content and anthocyanin content in the petals cells. The most important results showed that 600 μl L-1 of thyme essence in the container of the cut flowers due to its antioxidant and antibacterial properties, increased the lifespan of the flowers compared with the control for 4 days. Also, 2000 μM L-1of salicylic acid due to the improved ability of the tissue defense system of the petals via arising of the resistance to oxidative stress of cells increased the life span of the cut flowers from 4 days to 8 days.

Teucrium polium L. is one of the well-known medicinal and aromatic plants. In this study, we have used the SCoT marker to determine genetic variation among 17 genotypes of Teucrium polium collected from Kermanshah province, Iran. All of the SCoT primers showed 48 polymorphic bands. The primers of Sc20, Sc59 and Sc21 showed the highest number of band (6 bands) and Sc15 showed the lowest number of bands (2 bands). The mean polymorphic information content (PIC=0.361), marker index (MI= 1.525), Effective multiplex ratio (EMR= 4.197), polymorphism percentage (98.485%) and Resolving Power (RP=2.837) indices were calculated for all primers. The greatest similarity was between Gilan-gharb2 and Salas2 stations with 0.732 values. The lowest genetic similarity was between Naft-Shahr with Gilan-gharb1 and Gilan-gharb2 stations with 0.1. The cluster analysis group showed that the genotypes were classified into two groups, and the results of the clustering were confirmed by the use of molecular variance analysis (AMOVA) and principal components analysis (PCoA).

Nanoparticles due to their unique physicochemical properties, are widely used in biotechnology. Garlic (Allium sativum) is used as spice and drug for many years. Allicin as the best known active compound of garlic has a vast variety of biological effects. In this project effect of two abiotic elicitors including silver nanoparticles (AgNPs) and silver nitrate on growth and some biochemical parameters of garlic explants were studied. On silver nitrate-exposed samples; fresh weight, allicin, protein and cysteine contents, and catalase and guaiacol peroxidase activity was less than control. On AgNPs 25 ppm, growth, allicin, protein and cysteine contents was higher than untreated explants. Allicin content of AgNPs-treated explants was greater than the other treatments, on 25 ppm silver nitrate similar to control group and in 50 ppm-treated explants was the least. In conclusion because of the medicinal effects of allicin probably AgNPs could be a good candidate to increase allicin content.

Hyoscyamus reticulatus L. is a main source of tropane alkaloids, hyoscyamine and scopolamine. In the present study, hairy roots were prepared from two-weekly cultures of cotyledon transformed by A7 strain of Agrobacterium rhizogenes. The effect of different concentrations of Fusarium graminearum extract (0, 5, 10 and 20 mg/L) at different exposure times (24, 48 and 72 hours) on growth rate, antioxidant enzymes activity, total phenol, tropane alkaloids contents and expression level of Hyoscyanamine-6-beta-hydroxylase (h6h) gene were investigated. Data analysis results showed that fresh and dry weight under influence of high concentrations of Fusarium fungus extract was reduced. The activity of antioxidant enzymes including catalase, guaiacol peroxidase and ascorbate peroxidase as well as total phenol content in treated hairy roots was enhanced compared to control. GC analysis showed that the highest levels of hyoscyamine and scopolamine (27.5 and 40.41% respectively) were found in 5 and 10 mg of elicitor at 48 h exposure time. RT-PCR expression analysis results revealed that the highest expression of this gene was obtained in Fusarium fungus extract (10 mg/l) at 48 h exposure time. Based on these results, it is concluded that the Fusarium graminearum elicitor can be used as an effective stimulant for the production of secondary metabolites, including tropane alkaloids.

Liposomes are widely used as carriers for a large number of molecules in pharmaceutical studies. The stability and formation of liposomes is important in the drug delivery, and can be influenced by the phospholipid composition of the liposomal membrane. In this study, we are trying to investigate the effect of solvent type on the formation of daunoxome liposome (DSPC-CHOL). For this purpose, a molecular dynamics simulation method was used. The analysis of the radial distribution function that was performed to determine the formation and distribution of lipids, properly demonstrated that daunoxome liposome created dense nano-disk structure in a polar water environment and a spherical liposome in a non-polar water environment, and that the phospholipids have accumulated with homogeneous distribution. The solvent accessible surface area analysis showed a downward trend which indicates the accumulation of phospholipids alongside each other and the creation of the final structure. The analysis of the density and radius of gyration well showed that the final structures of the daunoxome liposome were formed in both environments. Due to the physio-chemical properties of 1,2-distearoyl-sn-glycero-3-phosphocholine phospholipid, it tends to create a spherical liposome structure. However, the type of solvent (ie., polar water environment) made the phospholipids to create a circular nano-disk structure in the polar water environment. According to other studies and our findings, polar water relatively to non-polar water with more force, pushing the lipid molecules to accumulate together, and making the lipid molecules in polar water to create a circular nano-disk structure.

GGPPS enzymes are responsible for the synthesis of geranyl geranyl diphosphate (GGPP), an important precursor for the production of variety terpenoids. In this study, by identifying the GGPPSs homologs UniProt database, the evolutionary process of this family was investigated using phylogenetic analysis, and the patterns of gene loss and gain over the course of evolution were inferred by parsimony-based optimization criterion. PLAZA database was used to study the role of whole genome duplication (WGD) and tandem gene duplication (TD). Results revealed that the GGPPS family is an expanding family and during plants evolution, GGPPS family has experienced expansion and contraction events in several alternate stages. Most of these expansions have been occurred as a result of the whole genome duplication (WGD) events. Nonetheless, tandem duplications (TDs) have occurred more in lineage specific expansions (LSEs). Furthermore, Protein Subcellular localization (PSL) analysis revealed that expansion process led to subfunctionalization in this protein family. Therefore, it seems that expansion in GGPPSs improve plants responses to stress and environmental stimuli, and ultimately, lead to a better adaptation to environmental conditions. Our analysis suggested that the selective pressure in different lineages of plants is variable and the positive selection was observed only in gymnosperms.

Growing faster and mass production of seed is always notable economically, industrially and pharmaceutically. Hence, the identification of the effective genes in growth, flowering and seed production is very valuable in the plants. The CURLY LEAF (CLF) is a key gene due to its important role in flowering inhibition. In this research, identification of CLF gene in black mustard (Brassica nigra L.), due to pharmaceutical and industrial consumption and its proximity to Arabidopsis model plant, was studied. For gene identification studies, the total RNA was extracted from the mature leaves in the vegetative stage. Gene expression was studied using extracted RNAs from leaves and shoot tips in both vegetative and generative stages as well as flower buds. Identification and expression were investigated after cDNA synthesis using the designed primers and the RT-PCR technique. The results confirmed a specific fragment of 665 nucleotides recorded in the gene bank as bnCLF (KT984485). The studies of phylogenetic tree showed that the CLF gene of the black mustard has a close relation with Brassicaceae family but the most homology was observed with Brassica rapa. The higher expression of CLF was observed in leaf and shoot tip at generative phase compared with vegetative phase. Further, the highest of expression amount was seen in floral buds in generative phase than leaf and shoot tip. Therefore, it seems that it is possible to accelerate flowering in some plants by identification and repression of this gene.