scholarly journals Different Gene Expression Response of Polish and Australian Raphidiopsis raciborskii Strains to the Chill/Light Stress

2020 ◽  
Vol 10 (16) ◽  
pp. 5437 ◽  
Author(s):  
Adam Antosiak ◽  
Nada Tokodi ◽  
Robert Maziarz ◽  
Mikołaj Kokociński ◽  
Agnieszka Brzozowska ◽  
...  
Keyword(s):  
Low Temperature ◽  
Light Stress ◽  
Compatible Solutes ◽  
Protein Translation ◽  
High Light ◽  
Stress Conditions ◽  
Gene Expression Response ◽  
Expression Of Genes ◽  
Continue Growth ◽  
Expression Response

R. raciborskii is known for growing under wide ranges of temperature and light. In temperate regions, however, low temperature and high light may serve as a stressful condition for invading tropical populations. The genetic basis of R. raciborskii’s adaptation to this combination of stresses are unknown. In this study, the growth rate and the expression of genes that may be crucial in the response to the chill/light stress of two R. raciborskii strains (differing in their climatic origin and toxicity) exposed to low temperature and high light were examined. Results showed that AMU-DH-30, a non CYN (cylindrospermopsin) producing strain isolated from the temperate region, exhibited under stress the upregulation of genes involved in the protein translation (rbp1, nusG, hflX), membrane fluidity (desA), photosynthetic activity (ccr2 and ftsH), and the accumulation of compatible solutes (asd). In contrast, a CYN producing Australian strain CS-505 was not able to adapt quickly and to continue growth during stress conditions. Intriguingly, CS-505 and AMU-DH-30 had a similar ability to resume growth when the stress conditions subsided. Moreover, in strain CS-505 the cyrB gene was significantly upregulated under the stress conditions. The presented results shed new light on the possible mechanisms involved in the response of R.raciborskii to chill/light stress.

scholarly journals Ecophysiological changes and spore formation: two strategies in response to low‐temperature and high‐light stress in Klebsormidium cf. flaccidum (Klebsormidiophyceae, Streptophyta) 1

2020 ◽  
Vol 56 (3) ◽  
pp. 649-661 ◽  
Author(s):  
Fátima Míguez ◽  
Andreas Holzinger ◽  
Beatriz Fernandez‐Marin ◽  
José I. García‐Plazaola ◽  
Ulf Karsten ◽  
...  
Keyword(s):  
Low Temperature ◽  
Light Stress ◽  
High Light ◽  
Spore Formation ◽  
High Light Stress

Effect of Membrane Fluidity on Photoinhibition of Isolated Thylakoids Membranes at Room and Low Temperature

2001 ◽  
Vol 56 (5-6) ◽  
pp. 369-374 ◽  
Author(s):  
Maya Velitchkova ◽  
Antoaneta Popova ◽  
Tzvetelina Markova
Keyword(s):  
Low Temperature ◽  
Membrane Fluidity ◽  
Light Stress ◽  
Photosynthetic Apparatus ◽  
Chemical Properties ◽  
Thylakoid Membranes ◽  
High Light Intensity ◽  
Photochemical Activity ◽  
High Light ◽  
Time Dependencies

The relationship between thylakoid membrane fluidity and the process of photoinhibition at room and low (4 °C) temperature was investigated. Two different membrane perturbing agents - cholesterol and benzylalcohol were applied to manipulate the fluidity of isolated pea thylakoids. The photochemical activity of photosystem I (PSI) and photosystem II (PSII), polarographically determined, were measured at high light intensity for different time of illumination at both temperatures. The exposure of cholesterol- and benzylalcohol-treated thylakoid membranes to high light intensities resulted in inhibition of both studied photochemical activities, being more pronounced for PSII compared to PSI. Time dependencies of inhibition of PSI and PSII electron transport rates for untreated and membranes with altered fluidity were determined at 20 °C and 4 °C. The effect is more pronounced for PSII activity during low-temperature photoinhibition. The data are discussed in terms of the determining role of physico-chemical properties of thylakoid membranes for the response of photosynthetic apparatus to light stress.

scholarly journals Genome-Wide Identification and Expression Analyses of the Fibrillin Family Genes Reveal Their Involvement in the Photoprotection in Cucumber

2018 ◽  
Author(s):  
Inyoung Kim ◽  
Sang-Choon Lee ◽  
Eun-Ha Kim ◽  
Kiwhan Song ◽  
Tae-Jin Yang ◽  
...  
Keyword(s):  
Low Temperature ◽  
Dna Sequences ◽  
Light Stress ◽  
High Light ◽  
Light Conditions ◽  
Transcript Levels ◽  
Photosynthetic Organisms ◽  
Conserved Domain ◽  
Genome Wide ◽  
Cucumber Genome

Fibrillin (FBN) is a plastid lipid-associated protein found in photosynthetic organisms from cyanobacteria to plants. In this study, 10 CsaFBN genes were identified in genomic DNA sequences of cucumber (Chinese long and Gy14) through database searches using the conserved domain of FBN and the 14 FBN genes of Arabidopsis. Phylogenetic analysis of CsaFBN protein sequences showed that there was no counterpart of Arabidopsis and rice FBN5 in the cucumber genome. FBN5 is essential for growth in Arabidopsis and rice; its absence in cucumber may be because of incomplete genome sequences or that another FBN carries out its functions. Among the 10 CsaFBN genes, CsaFBN1 and CsaFBN9 were the most divergent in terms of nucleotide sequences. Most of the CsaFBN genes were expressed in the leaf, stem, and fruit. CsaFBN4 showed the highest mRNA expression levels in various tissues, followed by CsaFBN6, CsaFBN1, and CsaFBN9. High-light stress combined with low temperature decreased photosynthetic efficiency and highly induced transcript levels of CsaFBN1, CsaFBN6, and CsaFBN11, which decreased after 24 h treatment. Transcript levels of the other seven genes were changed only slightly. This result suggests that CsaFBN1, CsaFBN6, and CsaFBN11 may be involved in photoprotection under high-light conditions at low temperature.

scholarly journals Transcriptome-based design of antisense inhibitors potentiates carbapenem efficacy in CREEscherichia coli

2020 ◽  
Vol 117 (48) ◽  
pp. 30699-30709
Author(s):  
Thomas R. Aunins ◽  
Keesha E. Erickson ◽  
Anushree Chatterjee
Keyword(s):  
Gene Expression ◽  
Protein Translation ◽  
Resistance Mechanisms ◽  
Transcriptomic Analysis ◽  
Gene Expression Response ◽  
Antibiotic Development ◽  
Resistance Factors ◽  
Inhibit Protein Translation ◽  
Significant Expression ◽  
Expression Response

In recent years, the prevalence of carbapenem-resistantEnterobacteriaceae(CRE) has risen substantially, and the study of CRE resistance mechanisms has become increasingly important for antibiotic development. Although much research has focused on genomic resistance factors, relatively few studies have examined CRE pathogens through changes in gene expression. In this study, we examined the gene expression profile of a CREEscherichia coliclinical isolate that is sensitive to meropenem but resistant to ertapenem to explore transcriptomic contributions to resistance and to identify gene knockdown targets for carbapenem potentiation. We sequenced total and short RNA to analyze the gene expression response to ertapenem or meropenem treatment and found significant expression changes in genes related to motility, maltodextrin metabolism, the formate hydrogenlyase complex, and the general stress response. To validate these findings, we used our laboratory’s Facile Accelerated Specific Therapeutic (FAST) platform to create antisense peptide nucleic acids (PNAs), gene-specific molecules designed to inhibit protein translation. PNAs were designed to inhibit the pathways identified in our transcriptomic analysis, and each PNA was then tested in combination with each carbapenem to assess its effect on the antibiotics’ minimum inhibitory concentrations. We observed significant PNA–antibiotic interaction with five different PNAs across six combinations. Inhibition of the geneshycA,dsrB, andbolApotentiated carbapenem efficacy in CREE. coli, whereas inhibition of the genesflhCandygaCconferred added resistance. Our results identify resistance factors and demonstrate that transcriptomic analysis is a potent tool for designing antibiotic PNA.

scholarly journals Stable Reference Gene Selection for RT-qPCR Analysis inSynechococcus elongatusPCC 7942 under Abiotic Stresses

2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Xiao Luo ◽  
Jiaxing Li ◽  
Tianliang Chang ◽  
Hongyan He ◽  
Yi Zhao ◽  
...  
Keyword(s):  
Reference Gene ◽  
Reference Genes ◽  
Time Course ◽  
Light Stress ◽  
Nacl Stress ◽  
High Light ◽  
Stress Conditions ◽  
Internal Reference ◽  
High Light Stress ◽  
Pcc 7942

Synechococcus elongatusPCC 7942 (S. elongatusPCC 7942) is a model cyanobacteria species for circadian clock mechanism studies. It has also been widely used as a bioreactor to produce biofuels and other metabolic products. Quantitative real-time PCR (qPCR) technology is the most commonly used method for studying the expression of specific genes, in which the relative expression level of target genes is calibrated by stably expressed internal reference genes. In this work, we examined the expression of nine candidate reference genes in time-course samples ofS. elongatusPCC 7942 under no treatment (control), NaCl-stress conditions, H2O2-stress conditions, and high light-stress conditions. Based on the qPCR amplification parameters, the stability ranking of these candidate reference genes was established by three statistical software programs, geNorm, NormFinder, and BestKeeper. Considering all the stress conditions or high light stress alone, the results showed that the combination ofprsandsecAwas the best choice for the double reference gene calibration method by qPCR. The combination ofsecAandppc,rimMandrnpA,rnpA,andilvDwas most stable under no treatment, NaCl-stress conditions, and H2O2-stress conditions, respectively.rimMwas stable under only special conditions and should be carefully chosen.16SandrnpBwere not suitable as internal reference genes forS. elongatusPCC 7942 qPCR experiments under all experimental conditions. To validate the above results, a cyanobacterial core clock gene,kaiC, was used to evaluate the actual performance of the optimized reference genes by qPCR, as well as the worst reference genes under different stress conditions. The results indicated that the best reference gene yielded more accurate calibration results for qPCR experiments carried out inS. elongatusPCC 7942 time-course samples.

Site selectivity of osteoblast gene expression response to thyroid hormone localized by in situ hybridization

1997 ◽  
Vol 272 (2) ◽  
pp. E212-E217 ◽  
Author(s):  
S. Suwanwalaikorn ◽  
M. Van Auken ◽  
M. I. Kang ◽  
S. Alex ◽  
L. E. Braverman ◽  
...  
Keyword(s):  
Gene Expression ◽  
In Situ Hybridization ◽  
Thyroid Stimulating Hormone ◽  
Mineral Density ◽  
Gene Expression Response ◽  
Expression Of Genes ◽  
Osteoblast Activity ◽  
Old Rats ◽  
Expression Response

We have previously reported that thyroid-stimulating hormone (TSH)-suppressive doses of L-thyroxine (L-T4) decrease femoral, but not vertebral, bone mineral density (BMD) in rats. L-T4-induced decreases in BMD were associated with increased expression of genes, reflecting osteoblast activity in mRNA extracted from whole femurs but not from vertebrae. To document that this skeletal selectivity reflected altered osteoblast activity, we studied gene expression by in situ hybridization in 8-wk-old rats treated with L-T4 (20 microg x 100 g body wt(-1) x day(-1)) for 4 wk. TSH-suppressive doses of L-T4 were associated with decreased femoral (0.299 +/- 0.005 vs. 0.273 +/- 0.005 g/cm2, P < 0.01), but not vertebral (0.222 +/- 0.004 vs. 0.218 +/- 0.003 g/cm2), BMD. In situ hybridization documented that L-T4 administration for 4 wk increased expression of osteocalcin and alkaline phosphatase mRNA in femoral, but not vertebral, osteoblasts. This study demonstrates a differential gene expression response of vertebral and femoral osteoblasts to L-T4. This altered degree of gene expression markers of osteoblast activity documented by in situ hybridization may in part explain the apparent clinical differences in the effect of L-T4 on femoral and vertebral BMD.

Sign in / Sign up

Export Citation Format

Share Document