The Static Magnetic Field Regulates the Structure, Biochemical Activity, and Gene Expression of Plants

Gene expression analysis and classification of mode of toxicity of polycyclic aromatic hydrocarbons (PAHs) in Escherichia coli

A comparative study on the role of conventional, chemical, and nanopriming for better salt tolerance during seed germination of direct seeding rice

The novel galactosyl transferase-like (SbGalT) gene from Salicornia brachiata maintains photosynthesis and enhances abiotic stress tolerance in transgenic tobacco.

Peroxisome-generated succinate induces lipid accumulation and oxidative stress in the kidneys of diabetic mice

The Structure And Expression Of Nuclear Genes In Higher Plants

β-aminobutyric acid alleviates the inhibition of production of soybean with exposure to phenanthrene stress via multilayer defense to maintain consistency

Magnetic fields, different to electric fields, can intrude into deeper layers of tissue, where they could modulate biochemical processes. In this context, we explored the cellular effects of specifically designed high‐performance micro‐magnet arrays which, in contrast to conventional magnets, generate high‐gradient magnetic fields not encountered in the environment. Exposure of monocytic cells to high‐gradient magnetic fields of various strength generated by micro‐magnet arrays induced cell swelling followed by accumulation of reactive oxygen species (ROS), and inhibition of cell proliferation. High levels of ROS may damage cellular structures and induce apoptosis. Consistently, prolonged exposure of cells to high‐gradient magnetic fields induced time‐dependent translocation of phosphatidylserine to the outer leaflet of the membrane. The extent of cell swelling, ROS production, and apoptosis correlated with the degree of the magnetic field gradient. On the contrary, when cells were exposed for prolonged time to a conventional high‐performance bulk magnet, which produces a strong, yet low‐gradient magnetic field, neither ROS nor apoptosis induction became detectable. These data clearly show that the static high‐gradient magnetic fields generated by the micro‐magnet arrays do affect monocytic cell functionality and may be used to manipulate intracellular biochemical processes.Grant Funding Source: Supported by DFG; ASCR, grant M100101219; and ANR, grant ANR‐11‐BSV5‐0101.

Several synthetic promoters containing a variety of commonly found cis-acting DNA sequence motifs were constructed to study the motif-motif and motif-protein interactions involved in gene expression in plants. Transient expression of the reporter gene gusA in tobacco leaves was used to demonstrate that several sequence elements can be arranged upstream of a basal promoter to function synergistically in enhancing gene expression. A cis-acting DNA motif could function as an activator by itself as well as a synergizing activator in the presence of other homologous as well as heterologous motifs in the neighbourhood. The function of a complex promoter comprising several activation motifs was arrested nearly completely in vivo, following titration with any one of the motifs. The results suggested a hierarchical assembly of several motif-binding factors, leading to the stabilization of the transcriptional complex formed on the TATA-box.

Gladiolus (Gladiolus grandiflorus Andrews) is a high-valued bulbous cut flower. However, the shorter postharvest life of the gladiolus, limits its marketing and commercial value. In the present investigation, the effect of lemon grass (LG) essential oil as an antimicrobial agent was studied towards increasing the vase life of gladiolus. The results revealed that as compared to control (distilled water), treatment with a lower concentration of 5 µL L−1 LG essential oil prolonged the vase life of gladiolus up to 11 days (d). Scanning Electron Microscope (SEM) observation indicated that the sample treated with 5 µL L−1 LG essential oil showed intact vasculature, suggesting reduced microbial blockage at the stem end which was further corroborated by microbial count. Biochemical analysis suggested an increased level of total soluble sugars, carotenoid content, lower MDA accumulation, and higher activity of antioxidant enzymes in LG treated flowers. Moreover, transcripts levels of genes associated with senescence viz., GgCyP1 and GgERS1a were downregulated, while expression of GDAD1 and antioxidant genes such as GgP5C5, GgPOD 1, GgMnSOD, and GgCAT1 were upregulated in LG treated cut spikes as compared to control. Among various treatments we have concluded that, the vase life of the gladiolus cut spike was improved along with the relative fresh flower weight and diameter of flower at the lower dose of 5 µL L−1 LG oil in the vase solution. Thus, LG oil as an eco-friendly agent has the potential to extend the postharvest life of cut flowers.

High salinity restricts plant growth and geographic distribution. Plant intracellular Na+/H+ (NHX) antiporters have critical roles in plant development and stress response. However, the molecular functions of RmNHXs in Rosa multiflora remain unclear. In this study, we identified 11 putative RmNHXs in R. multiflora according to the genome-wide analysis. The RmNHXs were classified into three classes. Most of the RmNHXs were responsive to salt stress, with the greatest upregulation being observed in RmNHX2. RmNHX2 was localized at the tonoplast. RmNHX2 overexpression resulted in the enhanced salt tolerance in tobacco, whereas virus-induced gene silencing (VIGS) of RmNHX2 in R. multiflora elevated salt susceptibility. Under salt treatment, the transgenic tobaccos achieved less reactive oxygen species (ROS) accumulation and higher activities of antioxidant enzymes, which complied with the upregulated expressions of antioxidant genes. Moreover, RmNHX2-overexpression lines had a lower level of Na+, a higher level of K+, and a lower Na/K ratio. In contrast to the mentioned, VIGS of RmNHX2 in R. multiflora exhibited the opposite phenotype, accompanied by a compromised salt tolerance. Regarded together, these results demonstrate that RmNHX2 enhances plant salt tolerance by maintaining proper ion homeostasis, as well as by accelerating ROS scavenging.

Studies on soybean GmNAC085 transcription factor revealed that the gene expression in plants was induced by water shortage treatments and its overexpression in the model plant Arabidopsis displayed improved plant tolerance characteristics towards drought stress. In this study, we continued analyzing the biological functions of GmNAC085 using transgenic soybean system overexpressing GmNAC085 gene, by targeting at a number of plant physiological features and biochemical activities in response to limited water growing condition. Compared to the wild-type, the transgenic line demonstrated that it possessed stress tolerance characters, including enhanced elongation of taproot, minimized reduction of shoot growth, lower intracellular H2O2 content and stronger peroxidase enzyme activity under drought condition. The results of this study therefore suggest the transgenic plants had better drought tolerance and the GmNAC085 plays important role in aiding plants to cope with water deficit condition, probably via regulating the growth of roots and shoots, and activities of reactive-oxygen-species- scavenging enzymes.

The activation-dependent induction of APN-(CD13) in T-cells is controlled at different levels of gene expression

Pleiotrophin is an important regulator of the renin–angiotensin system in mouse aorta

The PsbS gene product (PSII-S) which is an integral subunit of photosystem II has recently been reported to be a new type of pigment-binding protein [11]. The chlorophylls of the PSII-S protein exhibit weak excitonic coupling and this protein is stable also in the absence of pigments. Here we investigated the expression of the PsbS gene in etiolated spinach seedlings grown either in complete darkness or exposed to light of various qualities. The results obtained reveal that the PsbS gene expression in etiolated spinach plants is subjected to endogenous control. This developmental control occurs at different levels of gene expression and results in transient accumulation of the PsbS transcripts with progressing etiolation. During the first two days after emerging of the cotyledons from the seed coat the steady-state level of the PsbS transcripts is regulated mainly through increased transcriptional activity of the PsbS gene. Prolonged growth of the seedlings in the dark resulted in additional post-transcriptional control of the PsbS transcript level. Translational activity of PsbS mRNA estimated by an integration of mRNA into polysomal complexes shows that the translation rate of PsbS mRNA is less influenced by seedling age. The maximal rate of translation is reached at the first day after cotyledons emergence but the translational activity of PsbS mRNA remains still high (50% of maximum) in 8-day old etiolated spinach plants. In addition to the light-independent developmental control, the PsbS gene expression is positively regulated by phytochrome in etiolated seedlings exposed to light. Red light, however, negatively influences the abundance of PsbS transcripts at post-transcriptional level. Studies on blue or far-red light effects reveal that the accumulation of PsbS transcripts exhibits the characteristics of very-low-fluence responses of the phytochrome receptor.

Control of gene expression is crucial for several biotechnological applications, especially for implementing predictable and controllable genetic circuits. Such circuits are often implemented with a transcriptional regulator activated by a specific signal. These regulators should work independently of the host machinery, with low gratuitous induction or crosstalk with host components. Moreover, the signal should also be orthogonal, recognized only by the regulator with minimal interference with the host operation. In this context, transcriptional regulators activated by plant metabolites as flavonoids emerge as candidates to control gene expression in bacteria. However, engineering novel circuits requires the characterization of the genetic parts (e.g., genes, promoters, ribosome binding sites, and terminators) in the host of interest. Therefore, we decomposed the QdoR regulatory system of B. subtilis, responsive to the flavonoid quercetin, and reassembled its parts into genetic circuits programmed to have different levels of gene expression and noise dependent on the concentration of quercetin. We showed that only one of the promoters regulated by QdoR worked well in E. coli, enabling the construction of other circuits induced by quercetin. The QdoR expression was modulated with constitutive promoters of different transcriptional strengths, leading to low expression levels when QdoR was highly expressed and vice versa. E. coli strains expressing high and low levels of QdoR were mixed and induced with the same quercetin concentration, resulting in two stable populations expressing different levels of their gene reporters. Besides, we demonstrated that the level of QdoR repression generated different noise levels in gene expression dependent on the concentration of quercetin. The circuits presented here can be exploited in applications requiring adjustment of gene expression and noise using a highly available and natural inducer as quercetin.