Electromagnetic Radiation Disturbed the Photosynthesis of Microcystis aeruginosa at the Proteomics Level

Review on the impact of cell phone radiation effects on green plants

The aim of this review is to assess the impact of cell phone radiation effects on green plants. Rapid progress in networking and communication systems has introduced frequency- and amplitude-modulated technologies to the world with higher allowed bands and greater speed by using high-powered radio generators, which facilitate high definition connectivity, rapid transfer of larger data files, and quick multiple accesses. These cause frequent exposure of cellular radiation to the biological world from a number of sources. Key factors like a range of frequencies, time durations, power densities, and electric fields were found to have differential impacts on the growth and development of green plants. As far as the effects on green plants are concerned in this review, alterations in their morphological characteristics like overall growth, canopy density, and pigmentation to physiological variations like chlorophyll fluorescence and change in membrane potential etc. have been found to be affected by cellular radiation. On the other hand, elevated oxidative status of the cell, macromolecular damage, and lipid peroxidation have been found frequently. On the chromosomal level, micronuclei formation, spindle detachments, and increased mitotic indexes etc. have been noticed. Transcription factors were found to be overexpressed in many cases due to the cellular radiation impact, which shows effects at the molecular level.

Effect of 2850 MHz electromagnetic field radiation on the early growth, antioxidant activity, and secondary metabolite profile of red and green cabbage (Brassica oleracea L.)

The proliferation of wireless and other telecommunications equipment brought about by technological advances in the communication industry has substantially increased the radiofrequency radiation levels in the environment. The emphasis is, therefore, placed on investigating the potential impacts of radiofrequency radiation on biota. In this work, the impact of 2850 MHz electromagnetic field radiation (EMF-r) on early development, photosynthetic pigments, and the metabolic profile of two Brassica oleracea L. cultivars (red and green cabbage) was studied. On a daily basis for seven days, seedlings were exposed to homogeneous EMF-r for one, two, and four hours, and observations were carried out at 0-h, 1-h, and 24-h following the final dose. Irrespective of the duration of harvest, exposure to EMF-r resulted in a dose-dependent reduction in both root (from 6.3 cm to 4.0 cm in red; 6.1 cm to 3.8 cm in green) and shoot lengths (from 5.3 cm to ⁓3.1 cm in red; 5.1 cm to 3.1 cm in green), as well as a decrease in biomass (from 2.9 mg to ⁓1.1 mg in red; 2.5 to 0.9 mg in green) of the seedlings when compared to control samples. Likewise, the chlorophyll (from 6.09 to ⁓4.94 mg g-1 d.wt in red; 7.37 to 6.05 mg g-1 d.wt. in green) and carotenoid (from 1.49 to 1.19 mg g-1 d.wt. in red; 1.14 to 0.51 mg g-1 d.wt. in green) contents of both cultivars decreased significantly when compared to the control. Additionally, the contents of phenolic (28.99‒45.52 mg GAE g-1 in red; 25.49‒33.76 mg GAE g-1 in green), flavonoid (21.7‒31.8 mg QE g-1 in red; 12.1‒19.0 mg QE g-1 in green), and anthocyanin (28.8‒43.6 mg per 100 g d.wt. in red; 1.1‒2.6 mg per 100 g d.wt. in green) in both red and green cabbage increased with exposure duration. EMF-r produced oxidative stress in the exposed samples of both cabbage cultivars, as demonstrated by dose-dependent increases in the total antioxidant activity (1.33‒2.58 mM AAE in red; 1.29‒2.22 mM AAE in green), DPPH activity (12.96‒78.33% in red; 9.62‒67.73% in green), H2O2 content (20.0‒77.15 nM g-1 f.wt. in red; 14.28‒64.29 nM g-1 f.wt. in green), and MDA content (0.20‒0.61 nM g-1 f.wt. in red; 0.18‒0.51 nM g-1 f.wt. in green) compared to their control counterparts. The activity of antioxidant enzymes, i.e., superoxide dismutases (3.83‒8.10 EU mg-1 protein in red; 4.19‒7.35 EU mg-1 protein in green), catalases (1.81‒7.44 EU mg-1 protein in red; 1.04‒6.24 EU mg-1 protein in green), and guaiacol peroxidases (14.37‒47.85 EU mg-1 protein in red; 12.30‒42.79 EU mg-1 protein in green), increased significantly compared to their control counterparts. The number of polyphenols in unexposed and EMF-r exposed samples of red cabbage was significantly different. The study concludes that exposure to 2850 MHz EMF-r affects the early development of cabbage seedlings, modifies their photosynthetic pigments, alters polyphenol content, and impairs their oxidative metabolism.

Continuous Cropping Inhibits Photosynthesis of Polygonatum odoratum

Polygonatum odoratum (Mill.) Druce possesses widespread medicinal properties; however, the continuous cropping (CC) often leads to a severe consecutive monoculture problem (CMP), ultimately causing a decline in yield and quality. Photosynthesis is the fundamental process for plant growth development. Improving photosynthesis is one of the most promising approaches to increase plant yields. To better understand how P. odoratum leaves undergo photosynthesis in response to CC, this study analyzed the physiochemical indexes and RNA-seq. The physiochemical indexes, such as the content of chlorophyll (chlorophyll a, b, and total chlorophyll), light response curves (LRCs), and photosynthetic parameters (Fv/Fm, Fv/F0, Fm/F0, Piabs, ABS/RC, TRo/RC, ETo/RC, and DIo/RC) were all changed in P. odoratum under the CC system. Furthermore, 13,798 genes that exhibited differential expression genes (DEGs) were identified in the P. odoratum leaves of CC and first cropping (FC) plants. Among them, 7932 unigenes were upregulated, while 5860 unigenes were downregulated. Here, the DEGs encoding proteins associated with photosynthesis and carbon assimilation showed a significant decrease in expression under the CC system, such as the PSII protein complex, PSI protein complex, Cytochorome b6/f complex, the photosynthetic electron transport chain, light-harvesting chlorophyll protein complex, and Calvin cycle, etc., -related gene. This study demonstrates that CC can suppress photosynthesis and carbon mechanism in P. odoratum, pinpointing potential ways to enhance photosynthetic efficiency in the CC of plants.

Transcriptome profiling of flax plants exposed to a low-frequency alternating electromagnetic field

All living organisms on Earth evolved in the presence of an electromagnetic field (EMF), adapted to the environment of EMF, and even learned to utilize it for their purposes. However, during the last century, the Earth's core lost its exclusivity, and many EMF sources appeared due to the development of electricity and electronics. Previous research suggested that the EMF led to changes in intercellular free radical homeostasis and further altered the expression of genes involved in plant response to environmental stresses, inorganic ion transport, and cell wall constituent biosynthesis. Later, CTCT sequence motifs in gene promoters were proposed to be responsible for the response to EMF. How these motifs or different mechanisms are involved in the plant reaction to external EMF remains unknown. Moreover, as many genes activated under EMF treatment do not have the CTCT repeats in their promoters, we aimed to determine the transcription profile of a plant exposed to an EMF and identify the genes that are directly involved in response to the treatment to find the common denominator of the observed changes in the plant transcriptome.

Comparative Transcriptomic and Physiological Analyses Reveal Key Factors for Interstocks to Improve Grafted Seedling Growth in Tangor

Interstock is an important agronomic technique for regulating plant growth and fruit quality, and overcoming the incompatibility between rootstocks and scions; however, the underlying mechanisms remain largely unknown. In this study, the effects and regulatory mechanisms of tangor grafting, with and without interstocks, on the growth and development of scions were analyzed by combining morphology, physiology, anatomy and transcriptomics. Morphological and physiological analyses showed that interstocks (‘Aiyuan 38’ and ‘Daya’) significantly improved the growth of seedlings, effectively enhanced the foliar accumulation of chlorophyll and carotenoids, and increased the thickness of leaf tissues. Using ‘Aiyuan 38’ as the interstock, photosynthetic efficiency and starch content of citrus seedlings improved. Transcriptomics showed that genes related to photosynthesis and photosynthetic antenna proteins were upregulated in interstock-treated seedlings, with significant upregulation of photosystem PSI- and PSII-related genes. In addition, multiple key genes may be involved in plant hormone signaling, starch and sucrose metabolism, and transcriptional regulation. Taken together, these findings provide novel insights into the role of interstocks in regulating and contributing to the growth and development of grafted seedlings, and will further define and deploy candidate genes to explore the mechanisms of rootstock-interstock-scion interactions.

Pre-Exposure to Radiofrequency Electromagnetic Fields and Induction of Radioadaptive Response in Rats Irradiated with High Doses of X-Rays

Background

Some evidence shows that a pre-exposure to RF can mitigate the effects of subsequent exposures to high doses of ionizing radiation.

Objective

We aimed to assess the effect of a pre-exposure to non-ionizing RF radiation on survival, weight changes, food consumption, and water intake of lethally irradiated rats.

Material and Methods

In this case-control study, we used a commercial mobile phone (GSM, 900/1800 MHz) as well as a 2.4 GHz Wi-Fi router as the sources of pre-exposure to RF radiation. Forty-eight rats were randomly divided into six groups of control, "8 Gy X-rays", mobile phone, "mobile phone+8 Gy", Wi-Fi, and "Wi-Fi+8 Gy". Then, the survival fraction, weight loss, water, and food consumption changes were compared in different groups.

Results

The survival analysis indicated that the survival rates in all of the exposed animals ("8 Gy X-rays", "mobile phone+8 Gy", "Wi-Fi+8 Gy") were significantly lower than the control, "Wi-Fi", and "mobile phone" groups. The changes in survival rates of "mobile+8 Gy", "Wi-Fi+8 Gy", and 8 Gy alone were not statistically significant. However, food and water intake were significantly affected by exposure to both RF pre-exposures and exposure to high dose ionizing radiation.

Conclusion

To the best of our knowledge, the existence of a dose window for the induction of AR can be the cause of the lack of AR in our experiment. Our findings confirm that in a similar pattern with the adaptive responses induced by pre-exposure to ionizing radiation, the induction of adaptive response by RF-pre-exposures requires a minimum level of damage to trigger adaptive phenomena.

Effects of hydrogen peroxide on Scenedesmus obliquus: Cell growth, antioxidant enzyme activity and intracellular protein fingerprinting

Hydrogen peroxide (H₂O₂) is an environmental-friendly algicide and it is widely used to control algal blooms in aquatic ecosystems. However, the response of algal cell metabolic characteristics and intracellular protein profile under H₂O₂ stress is still not well understood. In the present study, the green alga Scenedesmus obliquus was exposed to different concentrations of H₂O₂ (0, 2, 6, 8 and 10 mg L^-1) to evaluate the changes in algal morphological, physiological, and proteomic features to H₂O₂ exposure. The results showed that 8 mg L^-1 of H₂O₂ could effectively inhibit the cell growth and photosynthetic activity of S. obliquus including chlorophyll-a content and chlorophyll fluorescence parameters. The increased activities of superoxide dismutase (SOD) and catalase (CAT) observed in this study indicate that cells exposure to H₂O₂ caused oxidative stress. The metabolic activity of S. obliquus was significantly decreased by H₂O₂ treatment. In terms of proteomic analysis, 251 differentially expressed proteins (DEPs) were successfully identified. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed significant protein enrichment in the metabolic pathways, photosynthesis, ascorbic acid, and alginate metabolism and phenylpropane biosynthesis of S. obliquus. The analysis of protein-protein interaction system shows that the pathways of photosynthesis and metabolic pathways of S. obliquus were essential to resist oxidative stress. Taking together, these results shed new lights on exploring the cell physiological metabolism and intracellular protein mechanisms of H₂O₂ inhibition on algal blooms.

Transcriptomic responses of Microcystis aeruginosa under electromagnetic radiation exposure

Electromagnetic radiation is an important environmental factor. It has a potential threat to public health and ecological environment. However, the mechanism by which electromagnetic radiation exerts these biological effects remains unclear. In this study, the effect of Microcystis aeruginosa under electromagnetic radiation (1.8 GHz, 40 V/m) was studied by using transcriptomics. A total of 306 differentially expressed genes, including 121 upregulated and 185 downregulated genes, were obtained in this study. The differentially expressed genes were significantly enriched in the ribosome, oxidative phosphorylation and carbon fixation pathways, indicating that electromagnetic radiation may inhibit protein synthesis and affect cyanobacterial energy metabolism and photosynthesis. The total ATP synthase activity and ATP content significantly increased, whereas H+K+-ATPase activity showed no significant changes. Our results suggest that the energy metabolism pathway may respond positively to electromagnetic radiation. In the future, systematic studies on the effects of electromagnetic radiation based on different intensities, frequencies, and exposure times are warranted; to deeply understand and reveal the target and mechanism of action of electromagnetic exposure on organisms.

Growth properties and hydrogen yield in green microalga Parachlorella kessleri: Effects of low-intensity electromagnetic irradiation at the frequencies of 51.8 GHz and 53.0 GHz

The current research reports the effects of low-intensity extremely high frequency electromagnetic irradiation (EMI) of 51.8 GHz and 53.0 GHz on green microalga Parachlorella kessleri RA-002 isolated in Armenia. EMI demonstrated different effects on the growth properties of microalgae under various conditions. Under aerobic conditions a positive effect of EMI on the growth rate of P. kessleri and the content of photosynthetic pigments were observed. The data obtained indicates a significant role of O₂, since the enhancing effect of EMI was determined only under aerobic conditions. Meanwhile under anaerobic conditions EMI with both frequencies caused inhibition of algal growth and a decrease in the amount of photosynthetic pigments. EMI also inhibited the yield of H₂ production in P. kessleri, which was partially restored after 5-day cultivation due to the existence of protective mechanisms in this alga. The results might indicate membrane-bound mechanisms of EMI action on algae, which can be associated with the effects on photosynthetic pigments and membrane-associated enzymes responsible for H₂ production. The results are useful for the development of algae biotechnology and the possibility of using EMI as a factor which regulates the production of biomass and biohydrogen by green microalgae.

Treatment of Common Sunflower (Helianthus annus L.) Seeds with Radio-frequency Electromagnetic Field and Cold Plasma Induces Changes in Seed Phytohormone Balance, Seedling Development and Leaf Protein Expression

Treatment of plant seeds with electromagnetic fields or non-thermal plasmas aims to take advantage of plant functional plasticity towards stimulation of plant agricultural performance. In this study, the effects of pre-sowing seed treatment using 200 Pa vacuum (7 min), 5.28 MHz radio-frequency cold plasma (CP -2, 5, and 7 min) and electromagnetic field (EMF -5, 10, 15 min) on seed germination kinetics, content of phytohormones, morphometric parameters of seedlings and leaf proteome were assessed. CP 7 min and EMF 15 min treatments caused 19-24% faster germination in vitro; germination in the substrate was accelerated by vacuum (9%) and EMF 15 min (17%). The stressors did not change the seed germination percentage, with exception of EMF 5 min treatment that caused a decrease by 7.5%. Meanwhile both CP 7 min and EMF 15 min treatments stimulated germination, but the EMF treatment resulted in higher weight of leaves. Stressor-specific changes in phytohormone balance were detected in seeds: vacuum treatment decreased zeatin amount by 39%; CP treatments substantially increased gibberellin content, but other effects strongly varied with the treatment duration; the abscisic acid content was reduced by 55-60% after the EMF treatment. Analysis of the proteome showed that short exposure of seeds to the EMF or CP induced a similar long-term effect on gene expression in leaves, mostly stimulating expression of proteins involved in photosynthetic processes and their regulation.