Journal of Molecular and Cellular Researches
Year:2016 | Volume:29 | Issue:2 |Papers Count:10

Physical and chemical mutagenesis techniques are used for creating genetic variability in many crop plants and several desire mutant lines have been developed by mutagenesis. In this research, EMS mutagen was applied to create genetic variability in rice (cv. Neda), and its mutagenesis effect was investigated in drought tolerance improvement. M2 mutants were evaluated at germinating and seedling stages under osmotic stress of PEG (-0.8 MPa) which resulted to isolating 9 drought tolerant lines. The lines along with their original cultivar also were evaluated in field under restricted irrigation regime which two mutants viz. MT90 and MT149 based on stress tolerance index (STI) were identified as drought tolerant lines. ISSR markers were used to assess genetic variability induced by mutation in mutant lines, 69.4 percent of which detected polymorphism between original cultivar and mutant lines. Mutation-induced genetic variation was estimated equal to 23.5 percent in the studied genotypes and cluster analysis using UPGMA method differentiated them into three main classes which mutants-containing groups produced higher yield and STI relative to original cultivar group under drought stress. Based on the results, MT149 mutant can be introduced as a drought tolerant line at both seedling and whole plant stages. It can be concluded that EMS-induced mutation had a desire effect in developing drought tolerant mutants and ISSR markers can be applied for differentiating drought tolerant mutants in rice mutation derived populations.

TRR14 is a small protein which is located in chloroplast. This protein was first identified in screening of trehalose resistant (TRR14) Arabidopsis seedlings. The aim of present study was physiological and molecular investigation of TRR14 re-transformed (T17) seedlings under salt stress, compared to wild type Arabidopsis seedlings (WT). For this purpose, WT and T17 seeds were grown on MS medium complemented with 0, 75, 100 and 150 mM NaCl. The results showed that under salt stress, the germination rate and trehalase activity in T17 seedlings were higher than WT. Meanwhile the results showed that anthocyanin level in WT seedlings was higher than T17 under salt stress. The Na level was highly increased in WT seedlings under 75 mM NaCl treatment, compared to T17 seedlings. The K measurements revealed that the K level in T17 seedling was 3 times more than WT seedling when grown on MS medium. But K level was decreased under 75 mM NaCl treatment in both WT and T17 seedlings. On the other hand, by adding NaCl to medium culture, the shape and size of epidermal cells were changed in both WT and T17 seedlings. While stomata numbers increased in WT leaves under NaCl treatment, it remained unchanged in T17 seedlings. The gene expression pattern showed that trehalase and TRR14 expression were increased under salt stress.

Monoclonal antibodies are heterotetramers consisting of four peptide chains-two identical light (L) chains and two identical heavy (H) chains and simultaneous equimolar expression of the corresponding genes is required to stable produce and assembly into a functional antibody. In order to co-express of multiple genes, different systems have been developed such as internal ribosome entry site (IRES) based vectors. IRES sequences are genetic elements that can drive cap-independent translation initiation of cistrons located downstream of the element. In this study, we constructed a bicsitronic vector for co-expression of genes encoding the H and L chains of the antibreast cancer antibody trastuzumab (Herceptin®) using an IRES sequence derived from the Nicotiana tabacum heat-shock factor 1 (NtHSF1). The effectiveness of construction was evaluated in N. tabacum using agroinfiltration method. Bisictronic expression of transgenes at the RNA transcription level was detected by semi-quantitative RT-PCR analysis. Western blot analyses revealed the efficient accumulation of tetrameric form of trastuzumab in tobacco leaf tissues and antibody content were ca. 0.44% of total soluble protein within 7 days after infiltration. The results of this study demonstrate the efficacy of a plant derived IRES element for bicistronic expression of heteromultimeric proteins.

In order to investigate the allelopathic effects of leaf extracts of E. globulus on germination and seedling growth of eggplant cv. Mahali Jahrom an experiment was carried out using a completely randomized design arranged in a factorial scheme with 3 replications. Treatments included 5 types of extracts including aqueous, methanolic, ethyl acetate, acetonic and benzene and different concentrations of extract at 5 level (0, 1.25, 2.5, 5 and 10 gram per liter). At the end of experiment germination percentage, germination rate, shoot length, root length, fresh and dry weights of seedling were measured. Result indicated that the inhibitory effect was proportional to the concentrations of the extracts and higher concentration had the strongest inhibitory effect on germination and seedling growth. Results also revealed that in all cases ethyl acetate had most negative effect on germination and seedling growth of eggplant whereas aqueous extract followed by acetonic extract caused highest germination percentage, germination rate and seedling growth.

Phytoremediation efficiency -a cost effective and environmentally sound technology to clean up contaminated soil - is reduced considering abiotic stresses. The research objective was to determine the effects of aged petroleum contaminated soil (10% W/W: Total petroleum Hydrocarbons) on two grasses specious (wild oat and barley) during the phytoremediation process. In addition the effects of petroleum degrading rhizobacteria inoculation were evaluated on plant growth promotion and decreasing toxicity of petroleum hydrocarbons. Results demonstrated that petroleum contaminated soil reduced growth, photosynthetic pigments and increased hydrogen peroxide (H2O2), MDA (malondialdehyde), enzymatic antioxidants (catalase and peroxidase) and NCDE and COR2 gene transcripts that indicate oxidative stress happened because of petroleum pollution similar to other common abiotic stress. a/b chlorophyll ratio enhancement and more decrease in shoot dry weight in wild oat showed barley was more tolerate to petroleum pollution. Bacterial inoculation reduced petroleum contamination toxicity and improved plant growth especially in wild oat.

Malononitrile, CH2(CN)2 is an aliphatic dinitrile, which uses in the production of herbicides, anti-cancer drugs and dyes. In the present study, malononitrile hydrolyzing bacteria screened from sewage with using MM1 media containing 1 % malononitrile. This strain was identified with biochemical and molecular methods. At first, malononitrile hydrolyzing activity of this strain determined with colorimetric method. The isolate AKH25, with high enzyme activity was selected and 16S rRNA gene was amplified and sequenced by PCR method and designed primers. Comparison of 16S rRNA gene of AKH25 (KM229757) with the other deposited 16S rRNA genes in NCBI showed that this strain is Pantoea agglomerans from Enterobacteriaceae family. In another study, the bacterial growth curve and ammonia liberated in the presence of different malononitrile concentration was considered. Results showed that, the highest malononitrile decomposition value was detected as releasing of 1.48 and 3.33 mM ammonia from 2.0 and 5.0 mM malononitrile, after 21 h of incubation during the stationary phase, respectively. According to this research, the Iranian Pantoea agglomerans strain AKH25 can be used as a suitable candidate for removing malononitrile from contaminated environments.

The transfersomes are ultraflexible vesicles, which due to their elastomechanic properties are able to penetrate into pores smaller than their own size, and thereby have the potential to deliver drugs to the skin. In this study growth hormone transfersomes were constructed from two formula made of phospholipids, sodium deoxycholate (f1) and sodium lauryl sulphate (f2) as surfactants. There are different ways of obtaining transfersomes with a specified size range. One of the methods is the use of sonication to regulate their size and dimensions. Accordingly, in order to study transfersomes carrying the growth hormone, the vesicles were sonicated using both the probe and bath methods. In each case, dimensions, dispersity, the zeta potential of transfersomes and biological activity of the growth hormone were measured during three different time cycles of sonication. The results showed that during investigation of all the different time periods, growth hormone activity was found to decrease further following probe sonication when compared to that of bath sonication. Therefore, vesicle size and zeta potential were measured in the probe sonication tests. The mean size was found to vary between 242.6 to 190.6 and 81.37 to 159.6, for the f1 and f2 vesicles, respectively. The zeta potential of the f1 transfersomes was more negative than that of f2.

In order to detect QTLs controlling root and shoot morphological traits, 96 lines from a cross between two varieties Sepidroud and Anbarboo were sown in Research farm located in the Ali Abad city in 2011. Evaluated traits were included average of root length, total root length, number of roots less than 5 cm, the number of roots between 7- 6 cm the number of roots between 20-8 cm, number of roots more than 30 cm, root number, plant height, root fresh weight, root dry weight, root volume and weight of the clusters, the number of clusters, straw weight, panicle length, number of grains per panicle, primary spikelets per panicle. Linkage map was constructed using 124 microsatellite markers and 264 AFLP markers during the years 2011 to 2012 in the Laboratory of Genetics and Plant Breeding in Gonbad Kavous University. In the linkage map 1950.4cM of the rice genome has been covered. In this study region of E100- M140-7-RM3520, E060-M160-3-RM1359 aand RM276-E120-M160-3 controlled several traits in normal conditions in chromosomes 1, 4 and 6, respectively. The results showed that the QTLs controlling root dry weight, root fresh weight and number root overlaped with each other on chromosome 7. QTLs for root volume (qRVN-2a, qRVN-4a and qRVN-4b) and roots (qRNN-4) were identified as major effect QTLs. These QTLs explained more than 20% of the phenotypic variation. The detected major effect QTLs in this study can be used in marker-assisted selection breeding programs after validation.

Polygalacturonases (GH28) hydrolyze the pectic substances, present mostly in plants. Polygalacturonases are widely distributed among microorganisms and higher plants. Microbial polygalacturonases, mainly produced by fungi, are utilized in many largescale industrial processes. Production of a polygalacturonase from a fungal phytopathogen, M. phaseolina was evaluated. M. phaseolina was cultured in production medium. The crude extract was separated from fungal cells. The highest enzyme activity was observed at 60oC. This enzyme had a high stability at wide ranges of pH and temperature and exhibited a t1.2 of 400 min at 70oC. The value for free energy of the heat inactivation at the temperature of 70oC was about 108 kJ, suggesting its potential to be used as an industrial enzyme. Analysis of biochemical characteristics of polygalacturonase from different fungi using ProtParam demonstrated that the M. phaseolina polygalacturonase was amongst the most stable fungal polygalacturonases.

This study was carried out to evaluate the effects of salicylic acid on the peroxidase, catalase and polyphenoloxidase activities in potato Agria cultivar for reducing the pathogenesis of Rhizoctonia solani under greenhouse conditions. The potato minitubers (without any infection) were transferred to pots containing soil steril for growth. The sterilized soil of pots had infected by R. solani two weeks before planting. The 4 weeksold plants (7-8 leaves) have been treated by 0.1, 0.2, 0.5 and 1 mM Salicylic acid every week for 4 times. Results showed that as salicylic acid increased, polyphenoloxidase activities were increased in potato plants (healthy and infected) whereas were decreased peroxidase and catalase activities under the same conditions. On the other hand, it seems that due to decreased activites of catalase and peroxidase and production of reactive oxygen species (H2O2, OH-, O2-) which are toxic for fungi, so potato plants can be resistance to R. solani. Also, it seems that to increase polyphenoloxidase activity, defensive mechanisms such as lignification and build bridges transverse hydroxyproline in root cell walls cause strengthen in the root tissues, so potato plants can be resistance0020against R. solani.