MODERN GENETICS JOURNAL (MGJ)
Year:2013 | Volume:8 | Issue:1 (32)|Papers Count:13

After completion of the Arabidopsis genome sequencing project and identification of 25498 genes, the function of several genes defined putatively. For instance the function of seven genes in Arabidopsis defined as putative tyrosine aminotransferas which the function of three genes have been confirmed experimentally until now. In the present study, the function of putative gene from this family considered to be evaluated using complementation test with DL39 auxotroph bacteria. As a result of mutation in tyrosine aminotransferase gene, this bacterium is auxotroph for L-tyrosine amino acid. In order to evaluate the ability of Arabidopsis putative tyrosine aminotransferase gene to complement tyrosine aminotransferase deficiency in bacteria, the coding region of this gene was cloned into pQE expression vector and used for bacterial transformation. Successful complementation results in the restoration of the bacterial ability to grow in medium without L-tyrosine supplementation. Analysis of enzyme assay showed that the enzyme is able to catalyzes the conversion of tyrosine to 4-hydroxyphenylpyruvate. These results confirmed that this putative gene has tyrosine aminotransferase activity.

Genetic parameters of cocoon weight, cocoon shell weight and cocoon shell percentage was estimated in two commercial lines during three generations under individual selection and random selection schedule. The individual selection program included (A) individual selection based on cocoon weight and (B) individual selection based on cocoon shell weight. The data collected from two commercial lines 153 and 154 were used in the Iran Silkworm Research Centre. Genetic parameters of cocoon weight and cocoon shell weight were estimated using WOMBAT software and REML algorithm. For both selection methods, high heritability were estimated for cocoon weight and cocoon shell weight. Both lines had higher heritability for traits under individual selection. Since there are high and positive genetic correlation between cocoon weight and cocoon shell weight, so it is showed we can improve one trait using selection based on another trait. Generally based on obtained results, it must be noted we can improve cocoon weight average in the short term using strategy A. If our purpose is improvement of the cocoon shell weight in the hybrids, strategy B is effective and can be recommended. Also strategy A improved cocoon shell percentage.

Ziziphora tenuior named Kakooti in Iran is a medicinal plant that is traditionally used in some treatment of diseases, pain reduction and infection treatment. Kakooti is an aromatic annual plant and has a wide distribution in Iran. In this study, 13 morphological characters and 16 RAPD primers were used to evaluate genetic diversity of 39 samples of Kakooti from 21 geographic regions of Iran. Calculated genetic similarity between samples based on polymorphic bands was in the range of 0.19 to 0.77, and 16 applied primers indicated 90.3% polymorphism. Both molecular and morphological markers showed high degree of polymorphism in the samples. Correlation levels between RAPD and morphological markers was not significant (r=0.01). Results showed this species have a considerable diversity in Iran that can be a valuable genetic resource for breeding research on Kakooti in the future.

Golden grey mullet (Liza aurata) is a commercially valuable fish in southern coastal parts of the Caspian Sea. In this study, we have used six microsatellite locations to investigate the level of genetic variation of Liza aurata in Babolsar and Chalus in Mazandaran province. The results showed no conspicuous genetic variation in these two regions using Fst and AMOVA and a relatively high level of gene flow was found among populations. Genetic variations in Babolsar (mean number of alleles per locus, Na=12.833, mean effective number of alleles, Ne= 9.402, observed heterozygosity, Ho=0.756 and expected heterozygosity, He=0.887) and Chalus (Na=13.667, Ne=9.945, Ho=0.708 and He=0.882) were not statistically different.

Transgenic plastids offer unique advantages in plant biotechnology, including high-level foreign protein expression and reducing environmental contamination risks. Here, the development of a specific plastid vector for lettuce, (Lactuca sativa L. TN-96-39), was described using of rbcl and accD as target fragments, Prrn promoter, psbA terminator and a gene cassette for antibiotic resistance. The species-specific vector for plastid transformation to Lactuca sativa, called pCL 96-39 (TN-96-39 (Iranian line) chloroplast plasmid), has been sequenced. Plastid transformation was optimized by biolistic bombardment. Transfomants were confirmed by PCR and also histochemical test for GUS protein production. Beta-glucoronidase production was confirmed by SDS-PAGE electrophoresis in transformants. This system will open up new possibilities for the efficient production of edible vaccines, pharmaceuticals, and antibodies in plants.

Transcription factors are important regulators of gene expression in all biological processes and are important in genetics too. Based on our results using qRT-PCR technique, AT1g77640 gene belongs to the AP2 transcription factor family, involves in cell cycle control in Arabidopsis. To identify biological processes regulated by AT1g77640 in detail, molecular characterization of transgenic plants with modified levels of AT1g77640 expression (constitutive over expression and amiRNA) was performed using profiling technology. Additionally expression pattern of the studied TF was analyzed using promoter-GUS lines and publicly available microarray data. Consistent with our data activation of AT1g77640 in cell cultures had fluctuation. Activity of AT1g77640 gene in the cell suspension decreased in late G2 and M phases. Constitutive over expression of AT1g77640 in Arabidopsis influenced cell size and cell number and also decreased seed production. The expression pattern of the gene was determined by qRT-PCR and through GUS fusions, indicated preferential transcriptional activity including flower buds, hypocotyls, vascular tissues, cotyledon and auxiliary meristem.

The taxonomic status of the Iran blind cave barb, Iranocypris typhlops, is somehow ambiguous and molecular analysis can be helpful in clarifying its taxonomy. Based on the existing hypotheses on the systematic status of the blind cave barb, the 5' sequence of COI was used to analyze its systematic status compared to the species of the genera Barbus, Garra and a number of other cyprinids, especially Cyprinid species of Iran, inhabiting rivers in Zagross Mountains. The sequences reported in this study were among the first molecular sequences for the Iran blind cave barb, the first COI sequence for Garra rufa (in Iran) and were the first reports for the species including Capoeta aculeatae, Capoeta trutta, Barbus lacerta, Kosswigobarbus kosswigi, Kosswigobarbus sublimus, Luciobarbus barbulus, Luciobarbus esocinus and Cyprinion macrostomum. Based on the observations made in the phylogenetic analysis, no close relationship was inferred for the blind cave barb and the genera Barbus, Capoeta, Kosswigobarbus, Luciobarbus and Cyprinion. However, there was a close relationship between the blind cave barb and the species of the genus Garra, especially the native G. rufa. Finally, it might be possible to consider blind Iran cave barb as close relatives of G. rufa, which has experienced the miniaturization phenomenon during its evolution. Among the cave barb specimens analyzed, one discless fish carried a haplotype, formerly reported for the disced form of the blind cave barb. This observation can be inferred as an indication of the possibilities such as hybridization between the two disced and discless forms or the instability of disc bearing feature in the blind cave barbs, for which the clarification is in need of more detailed analysis.

The high efficiency of gene transfer to maize (Zea mays L.) using a standard binary vector is used widely in studies of genetic engineering and functional Genomics. The objective of the present study was to enhance efficiency of gene transfer to maize varieties using heat shock and hormones. To do this, embryo induction and plant regeneration from immature embryos of B73 and Mo17 cultivars immature embryos (1.5- 2 mm) were infected with Agrobacterium tumefaciens strain AGLO1 harboring pCAMBIA3301 binary vector containing gus gene. The immature embryos were treated by T1 (46oC for 3 min, on ice for 1 min, centrifugation in 20000 g at 4oC for 30 min) and T2 (without T1 treatment) treatments before inoculation with Agrobacterum. Moreover, the effects of Dithiothreitol (DTT) and Pluronic acid F68 (F68) detergents were studied on transformation efficiency by adding them to culture media. The results showed that heat shock and centrifugation treatments improved slightly genetic transformation of B73 but not on Mo17. The addition of DTT or F68 to co-culture medium led to a dramatic increase in T-DNA transfer to the B73, while there was no effects on Mo17 transformation. In B73, depending on the type of treatment, 18-5% of the immature embryos were produced resistant calli to phosphinotricin (PPT). Histochemical GUS assay on 8 weeks calli resistant to PPT and PCR analysis confirmed the transferring and expression of gus gene. These analyses showed 18% transformation frequency in T1+F68 treatment in comparation with 0% in T2-Detergents. Based on our results, the treatment T1+ F68 was suggested an efficient methodology to transfer genes by Agrobacterium to maize cultivar B73.

Both DNA genomic fragment and open reading frame (ORF) encoding a Trx h, called VvCxxS2, were isolated and cloned from grape (Vitis vinifera L.) berry tissue. The DNA genomic fragment of VvCxxS2 possesses two introns at positions identical to the Trx h genes from grape and higher plant. The exon-intron junctions obey the rule GT-AG, as in higher plant genes. The intron position analysis in the chlamydomonas reinhardtii and vertebrates Trx genes revealed that two introns of chlamydomonas and one intron from vertebrates Trx genes are located at the same positions with introns of higher plants Trxs h and f genes, strongly suggesting a common origin for green algae, higher plants Trxs h and f, and vertebrates. The intron position analysis in the Trx o genes showed that these genes have been subjected a late evolution and in contrast to Trxs h and f, contain a different pattern of evolution. The introns position in Trxs m, p, x, and y was also analyzed. These genes possess one intron between the regions encoding the transit peptide and the mature protein, and suggest a recent entry of other introns during late evolution. Totally, obtained results suggest that Trxs f, h, and o have a eukaryotic origin whereas Trxs m, x, y, and p are related to prokaryotic Trxs, indicating different patterns of evolution.

During the composing process, microorganisms involved in degradation of agricultural and municipal waste are of great importance. Therefore, identification of beneficial microorganisms could play an important role in improving the quality of the produced compost. Fungi play an effective role in degradation of organic matter, So the objective of the present study was to isolate and characterize effective fungal strains during composting process. The fungi were isolated from mature compost in Isfahan Compost manufacture using serial dilution method. The enzymatic activities (lipase, amylase, cellulose, xylanase and protease) of the isolates were measured by qualitative and quantitative methods. Three isolates with enzyme activity were isolated and used for more detailed studies. The isolated fungal strains showed a wide range of different enzymatic activities. Molecular identification of the selected strains was performed based on PCR amplification and sequencing of a 1100 bp fragment of fungal 18SrDNA using M13R and M13F primers. Phylogenic studies revealed that the isolated fungal strains belonged to Aspergillus fumigates which are commonly exist in composting process. According to Municipal Solid Waste enrich cellulosic, starchy and protein compounds and these three strains have high potential of producing degradation enzymes, application of these fungal strains as accelerator in composting process (microbial booster) with different enzyme activities can transform wastes rapidly, then the efficiency of compost.

To evaluate the silver nitrate as oxidative treatment and per-treatment of ascorbic acid on expression of catalase and super-oxide dismutase anti-oxidant genes in wheat, the experiment carried out in 2009 at research green house of GUASNR university. The experiment designed in factorial order by using Randomized Block with 4 replicates. Experiment treatments included three level of silver nitrate (0, 0.75, 1.5 mM), tow level of ascorbic acid (0, 20 mM) and tow wheat cultivars Falat and Tajan, sensitive and relatively resistance to oxidative stress respectively. Chemical treatment were applied by spray them on leaves at spikel appearance. Water spray used as control, for combined treatments the first one ascorbic acid was taken place on to plant followed 1 h later by silver nitrate. For all treatments leaf samples were taken 10 and 48 h after the last spray. Chlorophyll a, b content, TBARM measurement, super-oxide and hydrogen peroxide level and super-oxide dismutase and catalase gene expression were assigned. The result showed silver nitrate spray significantly reduced chlorophyll content in compare with control. Applying ascorbic acid followed 1 h later by silver nitrate resumed chlorophyll content in compared with silver nitrate spray, indicating anti oxidant role of ascorbic acid. In contrast to chlorophyll changes, TBARM level has increased by silver nitrate spray and relatively recoverd by combined treatment (ascorbic acid + silver nitrate). This was almost same for super-oxide ion and hydrogen peroxide levels. In all treatments super-oxide dismutase gene expression was more than catalase especially in Tajan cultivar.

The myostatin protein is a member of the transforming growth factor- b (TGF- b) that plays an important role in the development of the skeletall muscles. The myostatin gene is located on ovine chromosome 2 (OAR2) and consists of three exons and two introns. In some breeds, mutation of the myostatin gene has a significant effect on the increase of the body weight and carcass traits. This study has been carried out with the objective of polymorphism analysis in the exon 3 of myostatin in Karakul sheep breed, by PCR-RFLP method and its relationship with weight traits issues. Blood samples were individually randomly collected from 100 Karakul sheep in Karakul Sheep Breeding Station at Sarakhs. Genomic DNA was extracted by optimized clotted blood method. With a pair of predesigned primers, the 337 bp fragment of the exon 3 of myostatin gene was amplified. The PCR product was digested by HaeIII restriction enzyme to be used to detect genotypes. All samples in this locus were monomorph, with “mm” genotype. according to available reports and this results it is detected that the Iranian breeds have very low level of polymorphism, while the European breeds demonstrate higher level of mutated allel frequency. The lowness of this gene's frequency in Iranian breeds is of the genetic characteristic features of Iranian sheep breeds.