Often ignored and regarded as mere transcriptional noise, long noncoding RNAs (lncRNAs) are starting to be considered key regulators of gene expression across the Eukarya domain of life. In the model ...diatom Phaeodactylum tricornutum, we have previously reported the occurrence of 1,510 intergenic lncRNAs (lincRNAs), many of which displaying specific patterns of expression under phosphate fluctuation (Pi). Using strand-specific RNA-sequencing data we now expand the repertoire of P. tricornutum lncRNAs by identifying 2,628 novel natural antisense transcripts (NATs) that cover 21.5% of the annotated genomic loci. We found that NAT expression is tightly regulated by phosphate depletion and other naturally occurring environmental stresses. Furthermore, we identified 121 phosphate stress responsive NAT-mRNA pairs, the great majority of which showing a positive correlation (concordant pairs) and a small fraction with negative correlation (discordant pairs). Taken together our results show that NATs are highly abundant transcripts in P. tricornutum and that their expression is under tight regulation by nutrient and environmental stresses. Furthermore, our results suggest that in P. tricornutum Pi stress response NAT pairs predominantly regulate positively the expression of their cognate sense genes, the latter being involved in several biological processes underlying the control of cellular homeostasis under stress.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Phosphorus (P) is an essential element to all living cells, yet fluctuations in P concentrations are recurrent in the marine environment. Diatoms are amongst the most successful phytoplankton groups, ...adapting to and surviving periods of suboptimal conditions and resuming growth as soon as nutrient concentrations permit. A knowledge of the molecular underpinnings of diatom ecological success is, however, still very incomplete. By strand‐specific RNA sequencing, we analyzed the global transcriptome changes of the diatom Phaeodactylum tricornutum in response to P fluctuations over a course of 8 d, defining five distinct physiological states. This study reports previously unidentified genes highly responsive to P stress in P. tricornutum. Our data also uncover the complexity of the P. tricornutum P‐responsive sensory and signaling system that combines bacterial two‐component systems with more complex pathways reminiscent of metazoans. Finally, we identify a multitude of novel long intergenic nonprotein coding RNAs (lincRNAs) specifically responsive to P depletion, suggesting putative regulatory roles in the regulation of P homeostasis. Our work provides additional molecular insights into the resilience of diatoms and their ecological success, and opens up novel routes to address and explore the function and regulatory roles of P. tricornutum lincRNAs in the context of nutrient stress.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NMLJ, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Understanding of the molecular responses underpinning diatom responses to ocean acidification is fundamental for predicting how important primary producers will be shaped by the continuous rise in ...atmospheric CO
2
. In this study, we have analyzed global transcriptomic changes of the model diatom
Phaeodactylum tricornutum
following growth for 15 generations in elevated
p
CO
2
by strand-specific RNA sequencing (ssRNA-seq). Our results indicate that no significant effects of elevated
p
CO
2
and associated carbonate chemistry changes on the physiological performance of the cells were observed after 15 generations whereas the expression of genes encoding histones and other genes involved in chromatin structure were significantly down-regulated, while the expression of transposable elements (TEs) and genes encoding histone acetylation enzymes were significantly up-regulated. Furthermore, we identified a series of long non-protein coding RNAs (lncRNAs) specifically responsive to elevated
p
CO
2
, suggesting putative regulatory roles for these largely uncharacterized genome components. Taken together, our integrative analyses reveal that epigenetic elements such as TEs, histone modifications and lncRNAs may have important roles in the acclimation of diatoms to elevated
p
CO
2
over short time scales and thus may influence longer term adaptive processes in response to progressive ocean acidification.
Aim. To evaluate the efficacy of dentifrice containing brazilian red propolis (BRP) in adolescents under orthodontic treatment. Materials and Methods. This is a randomized, double-blind, clinical ...trial. A total of 92 participants free from caries were randomized into 2 groups; the first received fluoride dentifrice, and the second received fluoride dentifrice incorporated with BRP. The gingival bleeding index (GBI) was recorded, and saliva was collected on the baseline (D0) and after 28 days (D28) for microbiological analysis. Data from GBI and Colony Forming Units (CFU) (log10) were expressed as mean and standard deviation. Results. The two groups reduced GBI significantly, with no difference in the intergroup analysis. In the intragroup analysis, it was observed that G2 (p<0.001) had a significant reduction for Gram-negative bacteria, while there was significance (p<0.001) in the intergroup analysis when compared with G1. For S. mutans bacteria, it was observed that only G2 had a statistically significant reduction (p<0.001), and there was significant reduction (p=0.006) in the intergroup analysis of the G2 group when compared with G1. Conclusions. Dentifrice containing BRP demonstrated better clinical and microbiological activity. Future studies are needed to better identify effects to establish the use of dentifrice containing propolis in biofilm control.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK, VSZLJ
Sporotrichosis in immunocompromised patients has a high morbidity and may cause deaths. Particularly, patients with acquired immunodeficiency syndrome (AIDS) with low T CD4 counts develop a chronic ...disease, with severe and widespread forms. Recently, the ability of
Sporothrix brasiliensis
, the main agent of zoonotic sporotrichosis, to increase its virulence in a diabetic patient without HIV infection was described. Since it was a unique finding, it is not known how often this occurs in patients with chronic and refractory sporotrichosis. The aim of this study is to compare sequential
Sporothrix
isolates obtained from patients with sporotrichosis and AIDS in order to detect changes in virulence-related phenotypes and acquisition of antifungal resistance during the evolution of the disease. Fungal growth in different substrates, antifungal susceptibility, thermotolerance, resistance to oxidative stress, and production of hydrolytic enzymes were evaluated. Correlations were assessed between clinical and phenotypic variables. Sixteen isolates, all identified as
S. brasiliensis
, obtained from five patients were studied. They grew well on glucose and N-acetyl-D-glucosamine, but poorly on lactate. Except from isolates collected from two patients, which were non-wild type for terbinafine, they were considered wild type for the antifungal drugs tested. Thermotolerance of the isolates was moderate to high. Except for phytase and phospholipase, isolates were able to produce virulence-related enzymes on different levels. Changes in all studied phenotypes were observed during the course of the disease in some patients. The results show that the HIV-driven immunosuppression is more relevant than fungal phenotypes on the unfavorable outcomes of disseminated sporotrichosis.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Adding biochar to soils and maintaining high earthworm biomasses are potential ways to increase the fertility of tropical soils and the sustainability of crop production in the spirit of agroecology ...and ecological engineering. However, a thorough functional assessment of biochar effect on plant growth and resource allocations is so far missing. Moreover, earthworms and biochar increase mineral nutrient availability through an increase in mineralization and nutrient retention respectively and are likely to interact through various other mechanisms. They could thus increase plant growth synergistically. This hypothesis was tested for rice in a greenhouse experiment. Besides, the relative effects of biochar and earthworms were compared in three different soil treatments (a nutrient rich soil, a nutrient poor soil, a nutrient poor soil supplemented with fertilization). Biochar and earthworm effects on rice growth and resource allocation highly depended on soil type and were generally additive (no synergy). In the rich soil, there were both clear positive biochar and earthworm effects, while there were generally only positive earthworm effects in the poor soil, and neither earthworm nor biochar effect in the poor soil with fertilization. The analysis of earthworm and biochar effects on different plant traits and soil mineral nitrogen content, confirmed that they act through an increase in nutrient availability. However it also suggested that another mechanism, such as the release in the soil of molecules recognized as phytohormones by plants, is also involved in earthworm action. This mechanism could for example help explaining how earthworms increase rice resource allocation to roots and influence the allocation to grains.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Ferromagnetic particles of azocasein composite (mAzo) were synthesized.•Crude extract from intestines of fish Nile tilapia (Oreochromis niloticus) was exposed mAzo, washed to remove unbound proteins ...by magnetic field and trypsin was leached off under high ionic strength.•Preparation was achieved containing specific activity about 60 times higher than that of the crude extract.•SDS-PAGE showed protein with molecular weight (24kDa) similar to reported Nile tilapia trypsin.•mAzo can be reused and applied to purify trypsin from other sources.
This work presents an inexpensive, simple and fast procedure to purify trypsin based on affinity binding with ferromagnetic particles of azocasein composite (mAzo). Crude extract was obtained from intestines of fish Nile tilapia (Oreochromis niloticus) homogenized in buffer (01g tissue/ml). This extract was exposed to 100mg of mAzo and washed to remove unbound proteins by magnetic field. Trypsin was leached off under high ionic strength (3M NaCl). Preparation was achieved containing specific activity about 60 times higher than that of the crude extract. SDS-PAGE showed that the purified protein had molecular weight (24kDa) in concordance with the literature for the Nile tilapia trypsin. The mAzo composite can be reused and applied to purify trypsin from other sources.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
• Background and Aims Reactive oxygen species are frequently produced when plants are exposed to abiotic stresses. Among the detoxication systems, two enzymes, ascorbate peroxidase and glutathione ...reductase (GR) play key roles. GR has also a central role in keeping the reduced glutathione pool during stress thus allowing the adjustments on the cellular redox reactions. The aim of this work was to study the variations in cytosolic and dual-targeted GR gene expression in the leaves of cowpea plants submitted to progressive drought, rapid desiccation and application of exogenous abscisic acid (ABA). • Methods Two cowpea (Vigna unguiculata) cultivars, one drought-resistant (‘EPACE-1’), the other drought-sensitive (‘1183’) were submitted to progressive drought stress by withholding irrigation. Cut-off leaves were air-dried or treated with exogenous ABA. Two GR cDNAs, one cytosolic, the other dual-targeted to chloroplasts and mitochondria were isolated by PCR and cloned in plasmid vectors. Reverse-transcription PCR was used to study the variations in GR gene expression. • Key Results Two new cDNAs encoding a putative dual-targeted and a cytosolic GR were cloned and sequenced from leaves of V. unguiculata. Drought stress induced an up-regulation of the expression of the cytosolic GR gene directly related to the intensity of the stress in both cultivars. The expression of dual-targeted GR was up-regulated by the drought treatment in the susceptible cultivar only. Under a fast desiccation, the ‘1183’ cultivar responded later than the ‘EPACE-1’, although in ‘EPACE-1’ it was the cytosolic isoform which responded and in ‘1183’ the dual-targeted one. Exogenous ABA enhanced significantly the activity and expression levels of GR in both cultivars after treatment for 24 h. • Conclusions These results demonstrate a noticeable activation in both cultivars of the antioxidant metabolism under a progressive water stress, which involves both GR genes in the case of the susceptible cultivar. Under a fast desiccation, the susceptible cultivar responded later than the resistant one, suggesting a weaker capacity of response versus the resistant one. Exogenous ABA probably acts on GR gene expression via a mediated signal transduction pathway.
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BFBNIB, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Summary
The formulation of gluten‐free breads is challenging, once the gluten network is responsible for the physical and sensory properties of bread. This study presents a novel concept for making ...gluten‐free breads using sugar substitutes. The quality of gluten‐free breads was analysed by means of physical (specific volume and colour), textural (firmness, elasticity and chewiness) and sensory properties (time‐intensity analysis and acceptance test). Time‐intensity analysis showed that the sample developed with raw sugar had a higher intensity of sweetness, and the sample with stevia had a higher intensity of yeast flavour. The sample with frutooligosaccharides (FOS) presented a higher acceptance by consumers. Sample with stevia presented the higher intensity of yeast flavour (8.10) and the lesser mean of specific volume (2.83 cm3.g−1); whereas sample with sugar who presented higher intensity of sweetness stimulus (5.20) also presented the higher mean of specific volume (3.80 cm3.g−1). The addition of prebiotic and sweetener opens up new opportunities to develop gluten‐free breads that may present similar properties to those of wheat‐based breads.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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