Molecular biology and (trans) gene expression technology in plant breeding
Dariush Taghavi; Mohammad Majidi; Saeed Mollaei; Bahman Panahi
Abstract
Shikonin is a naphthoquinone with some important medicinal properties and is found in gromwell plant. There are so many biotechnological approaches proposed for the productivity enhancement, and elicitation is recognized as one of the most effective strategies for increasing the production of secondary ...
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Shikonin is a naphthoquinone with some important medicinal properties and is found in gromwell plant. There are so many biotechnological approaches proposed for the productivity enhancement, and elicitation is recognized as one of the most effective strategies for increasing the production of secondary metabolites in plant in vitro cultures. Moreover, a deeper understanding of the mechanisms and factors affecting shikonin biosynthesis can led to the design of more intelligent and efficient biological production systems. To this aim, in the present study, the expression of some genes related to the shikonin biosynthetic pathway including PAL, 4CL, HMGR, GPPS and PGT in in vitro cultures of Lithospermum officinale in response to methyl jasmonate (MJ) at different times, were investigated by real-time PCR. The results showed that MJ had a significant effect on increasing gene expression levels in elicited samples compared to control samples. Additionally, we found that the studied genes respond to MJ with different pattern, in which the highest increase in gene expression level was observed for PGT while the lowest increase was observed for GPPS. Maximum and minimum transcript levels were obtained in most genes at 4 and 96 h post-elicitation, respectively. It was also found that phenylpropanoid pathway genes respond better to MJ than terpenoid pathway genes. The results of the present study would increase our knowledge about elicitor signal transduction pathways, and may be particularly useful for enhancement of shikonin production in plant cell cultures of L. officinale.
Plant breeding for abiotic & biotic stresses
Nafise Taghizadeh; Gholam Ali Ranjbar; Ghorban Ali Nematzadeh; Mohammad Reza Ramazani Moghaddam
Abstract
Salinity is one of the most important limitation factors in development of agricultural products. Cotton has a relative tolerance to salinity; however, salinity reduces its growth during germination and seedling stages. In this research, split-factorial design of time based on randomized complete block ...
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Salinity is one of the most important limitation factors in development of agricultural products. Cotton has a relative tolerance to salinity; however, salinity reduces its growth during germination and seedling stages. In this research, split-factorial design of time based on randomized complete block design with 3 replications was used. The real-time PCR results for, root, stem, and leaves of 14-day cotton seedlings of tolerant (Sepid) and sensitive (Thermus14) cotton cultivars with salinity levels from 0 to 16 ds.m-1 were analyzed at three time points, namely 0, 7 and 14 days after salinity stress. Selected genes for Real Time PCR reaction in current study were selected using Cytoscape 3.3.0 software. Results showed that the selected genes GhERF2, GhMPK2, GhCIPK6, GbRLK, GhNHX1, GhGST, GhTPS1 and Gh14-3-3 have positively responded to salinity stress and their expression in the root was higher than in stem and leaf. Moreover, the expression of tolerant genotype (Sepid) was higher than the sensitive cultivar (Thermus 14) one, however, a slight increase in sensitive genotypes was observed in a number of genes (GhERF2 and GhGST) 14 days after starting the stress treatment.
Plant breeding for abiotic & biotic stresses
Masoud Fakhrfeshani; Farajollah Shahriari-Ahmadi; Ali Niazi; Nasrin Moshtaghi; Mohammad Zare-Mehrjerdi
Abstract
Among abiotic stresses, salinity has been increasing over the time for many reasons like using chemical fertilizers, global warming and rising sea levels. Under salinity stress, the loss of water availability, toxicity of Na+ and ion imbalance directly reduces carbon fixation and biomass production in ...
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Among abiotic stresses, salinity has been increasing over the time for many reasons like using chemical fertilizers, global warming and rising sea levels. Under salinity stress, the loss of water availability, toxicity of Na+ and ion imbalance directly reduces carbon fixation and biomass production in plants. K+ is a major agent that can counteract Na+ stresses, thus the potential of plants to tolerate salinity is strongly dependent on their potassium nutrition. HKTs (High-affinity K+ Transporters) are a family of transporters that mediate Na+-specific or Na+-K+ transport and play a key role in the regulation of ion homeostasis. In this study, we intended to focus on Electrolyte Leakage, ratio of K+/Na+, transcriptomic responses of a subclass two HKT in the roots of Aeluropus littoralis under salt stress. We investigated a noticeably different expression pattern over studied time points and found a snappy increase of AlHKT and rebalance of K+ concentration. It can be suggested that the early and high response of a Na+-K+ coupled transporter acted as a part of A. littoralis salt tolerance.
Genetic engineering & plant breeding
Azadeh Mohseni; Ghorban Ali Nematzadeh; Ali Dehestani; Behzad Shahin; Elham Soleimani
Abstract
Plants are naturally exposed to frequent changes in environmental conditions such as salt stress affecting their growth and development, and consequently a considerable reduction in total productivity. Monodehydroascorbate reductase (MDHAR), a key enzyme in ascorbate-glutathione cycle, serves as an important ...
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Plants are naturally exposed to frequent changes in environmental conditions such as salt stress affecting their growth and development, and consequently a considerable reduction in total productivity. Monodehydroascorbate reductase (MDHAR), a key enzyme in ascorbate-glutathione cycle, serves as an important antioxidative enzyme in scavenging of reactive oxygen spices (ROS). In this study, MDHAR gene from Aeluropus littoralis was isolated using specific primers by RT-PCR and its expression variation was investigated at 0, 150, 300, 450 and 600 mM of NaCl through Real-time PCR. The results indicated that A. littoralis MDHAR gene compromised 1436 bp without any introns, showing a high similarity with Sorghum bicolor. The only alteration of MDHAR expression was observed at 300 mM NaCl, i.e. cytosolic MDHAR in both shoot and root was increased 1.3 and 1.4 fold compared to control samples. It could be concluded that accumulation of MDHAR reduces at Nacl concentrations higher than 300 mM.