scholarly journals Callusogenesis and in vitro morphogenesis of bean plants with contrast photoperiodic reaction by red light exposure

Author(s):  
Y. D. Batuieva ◽  
O. O. Avksentieva
2016 ◽  
Vol 28 (2) ◽  
pp. 167
Author(s):  
L. Y. Parra-Forero ◽  
A. Góngora ◽  
S. Romo-García ◽  
E. P. López Damian ◽  
G. D. Mendoza ◽  
...  

The effects of light on the steps of embryo manipulation have been described in several species, including humans. There are reports in which exposure of these cells to UV rays from sunlight affects them epigenetically, which could lead to meiotic arrest that would prevent normal maturation from the germinal vesicle (GV) to metaphase II (MII) stage, which would compromise subsequent embryo viability. Development to the blastocyst was not evaluated. The objective of the study was to observe the difference in maturation capacity (GV to MII) of prepubertal gilt oocytes under conditions of reduced ambient light. Thirty Duroc ovaries were recovered at slaughter and immersed in saline (0.9% NaCl) supplemented with penicillin-G (100 IU mL–1) and streptomycin sulfate (100 mg mL–1) at 29 to 34°C for transport to the laboratory where they were punctured with an 18-gauge needle attached to a 10-mL syringe. GV oocytes were selected with at least 3 layers of compact cumulus cells and were incubated with TCM-199 for 42 h in total with replacement with fresh maturation medium at 22 h. Oocytes were subsequently denuded using 0.1% hyaluronidase, fixed with 2% formaldehyde, and stained with Hoechst 33342 (10 min). Thereafter, oocytes were evaluated under a fluorescence microscope for the stage of meiosis: GV, metaphase I (MI), anaphase I/telophase I (ATI), and MII. GV oocytes were divided into two groups of 60 each as follows: Group 1 = handling in ambient light (1 change of culture medium and evaluation at the stereoscope); Group 2 = handling with reduced light (the change of medium was carried out in a dark room with red light on the stereoscope. Chi-square and Student’s t-test with Minitab 16.0 statistical program were used, and differences were considered significant at P < 0.05. There were significant differences in the percentages of maturation stages between Group 1 and Group 2, respectively: GV = 3.33, 3.33% (P = 0.45); MI = 20, 13.3% (P = 0.037); ATI = 33.3, 26.6% (P = 0.03); and MII = 43.3, 56.6% (P = 0.019). In conclusion, rate of maturation to MII was significantly higher with decreased light exposure. There was no difference in the GV groups probably because there was no manipulation at this stage. Further studies are necessary to determine the amount of light needed to optimize oocyte viability and to assess any potential effects on blastocyst production.


2020 ◽  
Vol 21 (6) ◽  
pp. 1993 ◽  
Author(s):  
Yukio Kurihara ◽  
Yuko Makita ◽  
Haruka Shimohira ◽  
Minami Matsui

The etiolation process, which occurs after germination, is terminated once light is perceived and then de-etiolation commences. During the de-etiolation period, monochromatic lights (blue, red and far-red) induce differences in gene expression profiles and plant behavior through their respective photoreceptors. ELONGATED HYPOCOTYL 5 (HY5), a bZIP-type transcription factor (TF), regulates gene expression in the de-etiolation process, and other bZIP TFs are also involved in this regulation. However, transcriptomic changes that occur in etiolated seedlings upon monochromatic light irradiation and the relationship with the bZIP TFs still remain to be elucidated. Here, we track changes in the transcriptome after exposure to white, blue, red and far-red light following darkness and reveal both shared and non-shared trends of transcriptomic change between the four kinds of light. Interestingly, after exposure to light, HY5 expression synchronized with those of the related bZIP TF genes, GBF2 and GBF3, rather than HY5 HOMOLOG (HYH). To speculate on the redundancy of target genes between the bZIP TFs, we inspected the genome-wide physical binding sites of homodimers of seven bZIP TFs, HY5, HYH, GBF1, GBF2, GBF3, GBF4 and EEL, using an in vitro binding assay. The results reveal large overlaps of target gene candidates, indicating a complicated regulatory literature among TFs. This work provides novel insight into understanding the regulation of gene expression of the plant response to monochromatic light irradiation.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Dwi Ariyanti ◽  
Kazunori Ikebukuro ◽  
Koji Sode

Abstract Background The development of multiple gene expression systems, especially those based on the physical signals, such as multiple color light irradiations, is challenging. Complementary chromatic acclimation (CCA), a photoreversible process that facilitates the control of cellular expression using light of different wavelengths in cyanobacteria, is one example. In this study, an artificial CCA systems, inspired by type III CCA light-regulated gene expression, was designed by employing a single photosensor system, the CcaS/CcaR green light gene expression system derived from Synechocystis sp. PCC6803, combined with G-box (the regulator recognized by activated CcaR), the cognate cpcG2 promoter, and the constitutively transcribed promoter, the PtrcΔLacO promoter. Results One G-box was inserted upstream of the cpcG2 promoter and a reporter gene, the rfp gene (green light-induced gene expression), and the other G-box was inserted between the PtrcΔLacO promoter and a reporter gene, the bfp gene (red light-induced gene expression). The Escherichia coli transformants with plasmid-encoded genes were evaluated at the transcriptional and translational levels under red or green light illumination. Under green light illumination, the transcription and translation of the rfp gene were observed, whereas the expression of the bfp gene was repressed. Under red light illumination, the transcription and translation of the bfp gene were observed, whereas the expression of the rfp gene was repressed. During the red and green light exposure cycles at every 6 h, BFP expression increased under red light exposure while RFP expression was repressed, and RFP expression increased under green light exposure while BFP expression was repressed. Conclusion An artificial CCA system was developed to realize a multiple gene expression system, which was regulated by two colors, red and green lights, using a single photosensor system, the CcaS/CcaR system derived from Synechocystis sp. PCC6803, in E. coli. The artificial CCA system functioned repeatedly during red and green light exposure cycles. These results demonstrate the potential application of this CCA gene expression system for the production of multiple metabolites in a variety of microorganisms, such as cyanobacteria.


2021 ◽  
Vol 723 (2) ◽  
pp. 022055
Author(s):  
A A Shkurkina ◽  
L P Khlebova ◽  
Yu V Melnikova ◽  
V P Vistovskaya ◽  
S E Mityukhina

1999 ◽  
Vol 557 ◽  
Author(s):  
S.J. Jones ◽  
R. Crucet ◽  
X. Deng ◽  
J. Doehler ◽  
R. Kopf ◽  
...  

AbstractUsing a Gas Jet thin film deposition technique, microcrystalline silicon (μc-Si) materials were prepared at rates as high as 15-20 Å/s. The technique involves the use of a gas jet flow that is subjected to a high intensity microwave source. The quality of the material has been optimized through the variation of a number of deposition conditions including the substrate temperature, the gas flows, and the applied microwave power. The best films were made using deposition rates near 16 Å/s. These materials have been used as i-layers for red light absorbing, nip single-junction solar cells. Using a 610nm cutoff filter which only allows red light to strike the device, pre-light soaked currents as high as 10 mA/cm2 and 2.2-2.3% red-light pre-light soaked peak power outputs have been obtained for cells with i-layer thicknesses near 1 micron. This compares with currents of 10-11 mA/cm2 and 4% initial red-light peak power outputs obtained for high efficiency amorphous silicon germanium alloy (a-SiGe:H) devices. The AM1.5 white light efficiencies for these microcrystalline cells are 5.9-6.0%. While the efficiencies for the a-SiGe:H cells degrade by 15-20% after long term light exposure, the efficiencies for the microcrystalline cells before and after prolonged light exposure are similar, within measurement error. Considering these results, the Gas Jet deposition method is a promising technique for the deposition of μc-Si solar cells due to the ability to achieve reasonable stable efficiencies for cells at i-layer deposition rates (16 Å/s) which make large-scale production economically feasible.


2018 ◽  
Vol 41 (1) ◽  
pp. 128-131 ◽  
Author(s):  
Tugce Ipek ◽  
Mariana Petronela Hanga ◽  
Andreas Hartwig ◽  
James Wolffsohn ◽  
Clare O’Donnell

2012 ◽  
Vol 63 (12) ◽  
pp. 1090 ◽  
Author(s):  
Huatao Chen ◽  
Xin Chen ◽  
Heping Gu ◽  
Xingxing Yuan ◽  
Hongmei Zhang ◽  
...  

An efficient regeneration and transformation system was established and optimised for adzuki bean (Vigna angularis (Willd.) Ohwi & Ohashi). 6-Benzylaminopurine at 5 mg L–1 was used to increase adventitious bud induction frequency. The highest frequency of shoot elongation was 92.8% when using a medium composition of MS salts combined with 0.1 mg L–1 of IAA, 0.5 mg L–1 of GA3, 1.0 mg L–1 of zeatin-riboside, 50 mg L–1 of aspartic acid, and 50 mg L–1 of glutamic acid. In vitro rooting was 100% when shoots were cultured on the solid MS medium supplemented with 1.0 mg L–1 of NAA. Reproducible transformation of epicotyl explants was developed using the A. tumefaciens EHA105 strain. Using a concentration of 40 mg L–1 of acetosyringone, 20 mm MES, and 5 mg L–1 of 6-benzylaminopurine in the co-cultivation medium, a transformation efficiency of 12.6% was attained. Using this transformation protocol, we obtained transgenic adzuki bean plants resistant to soybean mosaic virus by introducing the V. angularis VaPR3 gene.


2020 ◽  
Author(s):  
Deborah A. Smithen ◽  
Susan Monro ◽  
Mitch Pinto ◽  
John A. Roque III ◽  
Roberto M. Diaz-Rodriguez ◽  
...  

A new family of ten dinuclear Ru(II) complexes based on the bis[pyrrolyl Ru(II)] triad scaffold, where two Ru(bpy)<sub>2</sub> centers are separated by a variety of organic linkers, was prepared to evaluate the influence of the organic chromophore on the spectroscopic and in vitro photodynamic therapy (PDT) properties of the compounds. The bis[pyrrolyl Ru(II)] triads absorbed strongly throughout the visible region, with several members having molar extinction coefficients (e) ≥10<sup>4</sup> at 600–620 nm and longer. Phosphorescence quantum yields were generally less than 0.1% and in some cases undetectable. The singlet oxygen quantum yields ranged from 5% to 77% and generally correlated with their photocytotoxicities toward human leukemia (HL-60) cells regardless of the wavelength of light used. Dark cytotoxicities varied ten-fold, with EC<sub>50</sub> values in the range of 10–100 µM and phototherapeutic indices (PIs) as large as 5,400 and 260 with broadband visible (28 J cm<sup>-2</sup>, 7.8 mW cm<sup>-2</sup>) and 625-nm red (100 J cm<sup>-2</sup>, 42 mW cm<sup>-2</sup>) light, respectively. The bis[pyrrolyl Ru(II)] triad with a pyrenyl linker (5h) was especially potent, with an EC50 value of 1 nM and PI >27,000 with visible light and subnanomolar activity with 625-nm light (100 J cm<sup>-2</sup>, 28 mW cm<sup>-2</sup>). The lead compound 5h was also tested in a tumor spheroid assay using the HL60 cell line and exhibited greater photocytotoxcicity in this more resistant model (EC<sub>50</sub>=60 nM and PI>1,200 with 625-nm light) despite a lower dark cytotoxicity. The in vitro PDT effects of 5h extended to bacteria, where submicromolar EC<sub>50</sub> values and PIs >300 against <i>S. mutans</i> and <i>S. aureus </i>were obtained with visible light. This activity was attenuated with 625-nm red light, but PIs were still near 50. The ligand-localized <sup>3</sup>ππ* state contributed by the pyrenyl linker of 5h likely plays a key role in its phototoxic effects toward cancer cells and bacteria.<br><br>


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