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Edible insects have long been part of human diets in some countries, and they are expected to become an important alternative food source because of their nutritional value and favorable environmental impact. However, insects’ consumption safety and consumer acceptance are still significant barriers to market positioning, mainly in Western regions. Therefore, several processing technologies have been applied to develop insect-based food products and derivatives to increase consumer safety, shelf-life, and sensorial properties, including appearance. The processing pathway for insects as food might then be focused on eliminating such concerns. However, even though there is enough information related to processing techniques for edible insects, the use of the treated material has been limited as a substitute rather than a main constituted nutritional component. Moreover, there is little information about novel technologies and uses of insect derivatives compared to the minimally processed insect, as in the case of flours. This review presents the food safety (biological and chemical hazards) and cultural aspects of difficulties of eating insects and the role of processing raw material, extraction of insect derivatives (lipids and proteins), and food prototypes development on safety and consumer acceptance. Graphical abstract

Defense against genome invaders universally relies on RNA-guided immunity. Prokaryotic CRISPR/Cas and eukaryotic RNA interference pathways recognize targets by complementary base-pairing, which places the sequences of their guide RNAs at the center of self/nonself discrimination. Here, we explore the sequence space of PIWI-interacting RNAs (piRNAs), the genome defense of animals, and establish functional priority among individual sequences for the first time. Our results reveal that only the topmost abundant piRNAs are commonly present in every cell, while rare sequences generate cell-to-cell diversity in flies and mice. We identify a skewed distribution of sequence abundance as a hallmark of piRNA populations and show that quantitative differences of more than a thousand-fold are established by conserved mechanisms of biogenesis. Finally, our genomics analyses and direct reporter assays reveal that abundance determines function in piRNA-guided genome defense. Taken together, we identify an effective sequence space and untangle two classes of piRNAs that differ in complexity and function. The first class represents the topmost abundant sequences and drives silencing of genomic parasites. The second class sparsely covers an enormous sequence space. These rare piRNAs cannot function in every cell, every individual or every generation but create diversity with potential for adaptation in the ongoing arms race with genome invaders.

The enzymatic activity of Src-family kinase (SFKs) members Lck and Lyn is crucial to lymphocyte development and function. Lck has a T-cell restricted pattern of expression, however its ectopic presence has been documented in numerous pathological conditions. Amongst those, the erroneous presence of Lck in Chronic Lymphocytic Leukemia (CLL) B-cells has been suggested as a relevant factor for disease pathophysiology. However, the exact impact of Lck on the B-cell signaling apparatus remains unclear. In this work we sought to investigate the mechanistic basis of ectopic Lck in B-cell activation events. We examined the onset of proximal B-cell Receptor (BCR) signaling pathways and transcriptome alterations under the influence of ectopic Lck and compared it to events elicited by the predominant B-cell SFK member, Lyn.Our studies pinpointed signalling pathways exclusively governed by the constitutive activity of the two SFKs, excluding interferences from receptor/co-receptor engagement, influence of the microenvironment, alterations on their stereochemical integrity, or modulation of their regulators such as Csk or CD45, which also affect additional substrates.Lck- and Lyn-transduced signals sufficed to drive signalling events reminiscent of B-cells found in an activated state. We further discovered that the two kinases display differential susceptibility to mechanisms designed to prevent the onset of unscheduled signalling events, by keeping global levels of SFK activity under control. Finally, our analyses revealed a yet unrecognized role of SFK-driven signals in tipping the balance of cellular stress response regulation.

Retinoids are widely used in diseases spanning from dermatological lesions to cancer, but exhibit severe adverse effects. A novel all-trans-Retinoic Acid (atRA)-spermine conjugate (termed RASP) has shown previously optimal in vitro and in vivo anti-inflammatory and anticancer efficacy, with undetectable teratogenic and toxic side-effects. To get insights, we treated HaCaT cells which resemble human epidermis with IC50 concentration of RASP and analyzed their miRNA expression profile. Gene ontology analysis of their predicted targets indicated dynamic networks involved in cell proliferation, signal transduction and apoptosis. Furthermore, DNA microarrays analysis verified that RASP affects the expression of the same categories of genes. A protein-protein interaction map produced using the most significant common genes, revealed hub genes of nodal functions. We conclude that RASP is a synthetic retinoid derivative with improved properties, which possess the beneficial effects of retinoids without exhibiting side-effects and with potential beneficial effects against skin diseases including skin cancer.

T-box riboswitches (T-boxes) are essential RNA regulatory elements with a remarkable structural diversity, especially among bacterial pathogens. In staphylococci, all glyS T-boxes synchronize glycine supply during synthesis of nascent polypeptides and cell wall formation and are characterized by a conserved and unique insertion in their antiterminator/terminator domain, termed stem Sa. Interestingly, in Staphylococcus aureus the stem Sa can accommodate binding of specific antibiotics, which in turn induce robust and diverse effects on T-box-mediated transcription. In the present study, domain swap mutagenesis and probing analysis were performed to decipher the role of stem Sa. Deletion of stem Sa significantly reduces both the S. aureus glyS T-box-mediated transcription readthrough levels and the ability to discriminate among tRNAGly isoacceptors, both in vitro and in vivo. Moreover, the deletion inverted the previously reported stimulatory effects of specific antibiotics. Interestingly, stem Sa insertion in the terminator/antiterminator domain of Geobacillus kaustophilus glyS T-box, which lacks this domain, resulted in elevated transcription in the presence of tigecycline and facilitated discrimination among proteinogenic and nonproteinogenic tRNAGly isoacceptors. Overall, stem Sa represents a lineage-specific structural feature required for efficient staphylococcal glyS T-box-mediated transcription and it could serve as a species-selective druggable target through its ability to modulate antibiotic binding.

Background: The purpose of this study was to evaluate the expression of MMP-12 in patients with chronic rhinosinusitis with polyps (CRSwNP). Methodology: Tissue samples from 37 patients with CRSwNP undergoing functional endoscopic sinus surgery and healthy mucosa specimens from 12 healthy controls were obtained intraoperatively. The mRNA and protein expression levels of MMP-12 were quantified by real-time polymerase chain reaction and Western blotting, respectively. Results: mRNA levels of MMP-12 were significantly elevated in the CRSwNP tissue samples compared to those in control ones. The protein levels of MMP-12 showed a trend of increasing but with no statistical significance. Conclusions: Elevation of MMP-12 in patients with CRSwNP suggests its potential implication in the pathogenesis of the disease. The difference in the expression profile observed between mRNA and protein levels could be due to post-translational gene expression regulation. Our findings provide evidence that MMP-12 along with other MMPs may serve as a biomarker and therapeutic target in the management of the disease.

Mutations in human mitochondrial tRNAs (mt-tRNAs) are responsible for several and sometimes severe clinical phenotypes, classified among mitochondrial diseases. In addition, post-transcriptional modifications of mt-tRNAs in correlation with several stress signals can affect their stability similarly to what has been described for their nuclear-encoded counterparts. Many of the perturbations related to either point mutations or aberrant modifications of mt-tRNAs can lead to specific cleavage and the production of mitochondrial tRNA-derived fragments (mt-tRFs). Although mt-tRFs have been detected in several studies, the exact biogenesis steps and biological role remain, to a great extent, unexplored. Several mt-tRFs are produced because of the excessive oxidative stress which predominantly affects mitochondrial DNA integrity. In addition, mt-tRFs have been detected in various diseases with possible detrimental consequences, but also their production may represent a response mechanism to external stimuli, including infections from pathogens. Finally, specific point mutations on mt-tRNAs have been reported to impact the pool of the produced mt-tRFs and there is growing evidence suggesting that mt-tRFs can be exported and act in the cytoplasm. In this review, we summarize current knowledge on mitochondrial tRNA-deriving fragments and their possible contribution to gene expression regulation.

KRASG12C is among the most common oncogenic mutations in lung adenocarcinoma and a promising target for treatment by small-molecule inhibitors. KRAS oncogenic signaling is responsible for modulation of tumor microenvironment, with translation factors being among the most prominent deregulated targets. In the present study, we used TALENs to edit EGFRWT CL1-5 and A549 cells for integration of a Tet-inducible KRASG12C expression system. Subsequent analysis of both cell lines showed that cap-dependent translation was impaired in CL1-5 cells via involvement of mTORC2 and NF-κB. In contrast, in A549 cells, which additionally harbor the KRASG12S mutation, cap-dependent translation was favored via recruitment of mTORC1, c-MYC and the positive regulation of eIF4F complex. Downregulation of eIF1, eIF5 and eIF5B in the same cell line suggested a stringency loss of start codon selection during scanning of mRNAs. Puromycin staining and polysome profile analysis validated the enhanced translation rates in A549 cells and the impaired cap-dependent translation in CL1-5 cells. Interestingly, elevated translation rates were restored in CL1-5 cells after prolonged induction of KRASG12C through an mTORC1/p70S6K-independent way. Collectively, our results suggest that KRASG12C signaling differentially affects the regulation of the translational machinery. These differences could provide additional insights and facilitate current efforts to effectively target KRAS. ispartof: INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES vol:22 issue:4 ispartof: location:Switzerland status: published

Ribosomal RNA (rRNA) biogenesis takes place in the nucleolus, the most prominent condensate of the eukaryotic nucleus. The proper assembly and integrity of the nucleolus reflects the accurate synthesis and processing of rRNAs which in turn, as major components of ribosomes, ensure the uninterrupted flow of the genetic information during translation. Therefore, the abundant production of rRNAs in a precisely functional nucleolus is of outmost importance for the cell viability and requires the concerted action of essential enzymes, associated factors and epigenetic marks. The coordination and regulation of such an elaborate process depends on not only protein factors, but also on numerous regulatory non-coding RNAs (ncRNAs). Herein, we focus on RNA-mediated mechanisms that control the synthesis, processing and modification of rRNAs in mammals. We highlight the significance of regulatory ncRNAs in rRNA biogenesis and the maintenance of the nucleolar morphology, as well as their role in human diseases and as novel druggable molecular targets.

La is an abundant phosphoprotein that protects polymerase III transcripts from 3'-5' exonucleolytic degradation and facilitates their folding. Consisting of the evolutionary conserved La motif (LAM) and two consecutive RNA Recognition Motifs (RRMs), La was also found to bind additional RNA transcripts or RNA domains like internal ribosome entry site (IRES), through sequence-independent binding modes which are poorly understood. Although it has been reported overexpressed in certain cancer types and depletion of its expression sensitizes cancer cells to certain chemotherapeutic agents, its role in cancer remains essentially uncharacterized. Herein, we study the effects of La overexpression in A549 lung adenocarcinoma cells, which leads to increased cell proliferation and motility. Expression profiling of several transcription and translation factors indicated that La overexpression leads to downregulation of global translation through hypophosphorylation of 4E-BPs and upregulation of IRES-mediated translation. Moreover, analysis of La localization after nutrition deprivation of the transfected cells showed a normal distribution in the nucleus and nucleoli. Although the RNA binding capacity of La has been primarily linked to the synergy between the conserved LAM and RRM1 domains which act as a module, we show that recombinant stand-alone LAM can specifically bind a pre-tRNA ligand, based on binding experiments combined with NMR analysis. We propose that LAM RNA binding properties could support the expanding and diverse RNA ligand repertoire of La, thus promoting its modulatory role, both under normal and pathogenic conditions like cancer.

The EU-CardioRNA Cooperation in Science and Technology (COST) Action is a European-wide consortium established in 2018 with 31 European country members and four associate member countries to build bridges between translational researchers from academia and industry who conduct research on non-coding RNAs, cardiovascular diseases and similar research areas. EU-CardioRNA comprises four core working groups (WG1-4). In the first year since its launch, EU-CardioRNA met biannually to exchange and discuss recent findings in related fields of scientific research, with scientific sessions broadly divided up according to WG. These meetings are also an opportunity to establish interdisciplinary discussion groups, brainstorm ideas and make plans to apply for joint research grants and conduct other scientific activities, including knowledge transfer. Following its launch in Brussels in 2018, three WG meetings have taken place. The first of these in Lisbon, Portugal, the second in Istanbul, Turkey, and the most recent in Maastricht, The Netherlands. Each meeting includes a scientific session from each WG. This meeting report briefly describes the highlights and key take-home messages from each WG session in this first successful year of the EU-CardioRNA COST Action. © 2020 by the authors.

Date (Phoenix dactylifera L. Arecaceae) fruits and their by-products are rich in nutrients. The health benefits of dates and their incorporation into value-added products have been widely studied. The date-processing industry faces a significant sustainability challenge as more than 10% (w/w) of the production is discarded as waste or by-products. Currently, food scientists are focusing on bakery product fortification with functional food ingredients due to the high demand for nutritious food with more convenience. Utilizing date components in value-added bakery products is a trending research area with increasing attention. Studies where the researchers tried to improve the quality of bakery goods by incorporating date components have shown positive results, with several drawbacks that need attention and further research. The objective of this review is to present a comprehensive overview of the utilization of date components in bakery products and to identify gaps in the current knowledge. This review will help focus further research in the area of valorization of date by-products and thereby contribute to the generation of novel functional bakery products that meet consumer expectations and industry standards, thus generating income for the relevant industry and considerable alleviation of the environmental burden this waste and by-products contribute to. Only a few studies have been focused on utilizing date by-products and their extracts for baked goods, while a research area still remaining under-explored is the effect of incorporation of date components on the shelf life of bakery products.

Hydroxy-substituted tetrachlorodibenzo[b,e][1,4]dioxin and tetrachlorodibenzo[b,d]furans have been synthesized using 3,4-dichloroanisole, 2,3,6-trichlorophenol and 4,5-dichlorocatechol as starting materials and electrophilic and/or nucleophilic aromatic substitution reactions for the assembly of the dibenzo[b,e][1,4]dioxin and dibenzo[b,d]furan systems. The thus-obtained phenolic compounds were then alkylated with N-1-(4,4-dimethyl-2,6-dioxocyclohexylidene)ethyl (Dde)-protected 3-bromopropan-1-amine to give the corresponding N-Dde protected 3-aminopropoxy-substituted tetrachlorodibenzo[b,e][1,4]dioxin and tetrachlorodibenzo[b,d]furans, respectively. Hydrazinolysis-mediated Dde removal from the former compound provided the corresponding amino-substituted dioxin, which was coupled to carboxy-substituted magnetic beads affording magnetic beads coated by the amino-substituted dioxin. The latter is an attractive intermediate for the development of selective single-standard DNA (ssDNA) aptamers, which constitute molecular recognition elements in photonic biosensors with potential application to the monitoring of the dangerous environmental pollutants, dioxins having serious implications in human health.

Recently, it was discovered that exposure to mainstream antibiotics activate numerous bacterial riboregulators that control antibiotic resistance genes including metabolite-binding riboswitches and other transcription attenuators. However, the effects of commonly used antibiotics, many of which exhibit RNA-binding properties, on the widespread T-box riboswitches, remain unknown. In Staphylococcus aureus, a species-specific glyS T-box controls the supply of glycine for both ribosomal translation and cell wall synthesis, making it a promising target for next-generation antimicrobials. Here, we report that specific protein synthesis inhibitors could either significantly increase T-box-mediated transcription antitermination, while other compounds could suppress it, both in vitro and in vivo. In-line probing of the full-length T-box combined with molecular modelling and docking analyses suggest that the antibiotics that promote transcription antitermination stabilize the T-box:tRNA complex through binding specific positions on stem I and the Staphylococcal-specific stem Sa. By contrast, the antibiotics that attenuate T-box transcription bind to other positions on stem I and do not interact with stem Sa. Taken together, our results reveal that the transcription of essential genes controlled by T-box riboswitches can be directly modulated by commonly used protein synthesis inhibitors. These findings accentuate the regulatory complexities of bacterial response to antimicrobials that involve multiple riboregulators.

Deadenylases belong to an expanding family of exoribonucleases involved mainly in mRNA stability and turnover, with the exception of PARN which has additional roles in the biogenesis of several important non-coding RNAs, including miRNAs and piRNAs. Recently, PARN in C. elegans and its homolog PNLDC1 in B. mori were reported as the elusive trimmers mediating piRNA biogenesis. In addition, characterization of mammalian PNLDC1 in comparison to PARN, showed that is specifically expressed in embryonic stem and germ cells, as well as during early embryo development. Moreover, its expression is correlated with epigenetic events mediated by the de novo DNMT3b methyltransferase and knockdown in stem cells upregulates important genes that regulate multipotency. The recent data suggest that at least some new deadenylases may have expanded roles in cell metabolism as regulators of gene expression, through mRNA deadenylation, ncRNAs biogenesis and ncRNA-mediated mRNA targeting, linking essential mechanisms that regulate epigenetic control and transition events during differentiation. The possible roles of mammalian PNLDC1 along those dynamic networks are discussed in the light of new extremely important findings.

Amino acid availability in Gram-positive bacteria is monitored by T-box riboswitches. T-boxes directly bind tRNAs, assess their aminoacylation state, and regulate the transcription or translation of downstream genes to maintain nutritional homeostasis. Here, we report co-crystal and cryo-EM structures of Geobacillus kaustophilus and Bacillus subtilis T-box-tRNA complexes detailing their multivalent, exquisitely selective interactions. The T-box forms a U-shaped molecular vise that clamps the tRNA, captures its 3’-end using an elaborate “discriminator” structure, and interrogates its aminoacylation state using a steric filter fashioned from a wobble base pair. In the absence of aminoacylation, T-boxes clutch tRNAs and form a continuously stacked central spine, permitting transcriptional readthrough or translation initiation. A modelled aminoacyl disrupts tRNA-T-box stacking, severing the central spine and blocking gene expression. Our data establish a universal mechanism of amino acid sensing on tRNAs and gene regulation by T-box riboswitches, and exemplify how higher-order RNA-RNA interactions achieve multivalency and specificity.

Protein synthesis is a central and dynamic process, frequently deregulated in cancer through aberrant activation or expression of translation initiation factors and tRNAs. The discovery of tRNA-derived fragments, a new class of abundant and, in some cases stress-induced, small Noncoding RNAs has perplexed the epigenomics landscape and highlights the emerging regulatory role of tRNAs in translation and beyond. Skin is the biggest organ in human body, which maintains homeostasis of its multilayers through regulatory networks that induce translational reprogramming, and modulate tRNA transcription, modification and fragmentation, in response to various stress signals, like UV irradiation. In this review, we summarize recent knowledge on the role of translation regulation and tRNA biology in the alarming prevalence of skin cancer.

Background Sweet cherries (Prunus avium L.) are a nutritious fruit which are rich in polyphenols and have high antioxidant potential. Most sweet cherries are consumed fresh and a small proportion of the total sweet cherries production is value added to make processed food products. Sweet cherries are highly perishable fruit with a short harvest season, therefore extensive preservation and processing methods have been developed for the extension of their shelf-life and distribution of their products. Scope and approach In this review, the main physicochemical properties of sweet cherries, as well as bioactive components and their determination methods are described. The study emphasises the recent progress of postharvest technology, such as controlled/modified atmosphere storage, edible coatings, irradiation, and biological control agents, to maintain sweet cherries for the fresh market. Valorisations of second-grade sweet cherries, as well as trends for the diversification of cherry products for future studies are also discussed. Key findings and conclusions Sweet cherry fruit have a short harvest period and marketing window. The major loss in quality after harvest include moisture loss, softening, decay and stem browning. Without compromising their eating quality, the extension in fruit quality and shelf-life for sweet cherries is feasible by means of combination of good handling practice and applications of appropriate postharvest technology. With the drive of health-food sector, the potential of using second class cherries including cherry stems as a source of bioactive compound extraction is high, as cherry fruit is well-known for being rich in health-promoting components.

The effects of different solvents on the recovery of (i) extractable solids (ES), (ii) total phenolic compounds (TPC), (iii) total flavonoid content (TFC), (iv) vitamin C, and (v) antioxidant activity from lemon pomace waste were investigated. The results revealed that solvents significantly affected the recovery of ES, TPC, TFC, and antioxidant properties. Absolute methanol and 50% acetone resulted in the highest extraction yields of TPC, whereas absolute methanol resulted in the highest extraction of TFC, and water had the highest recovery of vitamin C. 50% ethanol, and 50% acetone had higher extraction yields for TPC, and TFC, as well as higher antioxidant activity compared with their absolute solvents and water. TPC and TFC were shown to be the major components contributing to the antioxidant activity of lemon pomace.

Summary The aim of this study was to optimise the aqueous extraction conditions for the recovery of phenolic compounds and antioxidant capacity of lemon pomace using response surface methodology. An experiment based on Box–Behnken design was conducted to analyse the effects of temperature, time and sample-to-water ratio on the extraction of total phenolic compounds, total flavonoids, proanthocyanidins and antioxidant capacity. Sample-to-solvent ratio had a negative effect on all the dependent variables, while extraction temperature and time had a positive effect only on TPC yields and ABTS antioxidant capacity. The optimal extraction conditions were 95 °C, 15 min and a sample-to-solvent ratio of 1:100 g mL−1. Under these conditions, the aqueous extracts had the same content of TPC and TF as well as antioxidant capacity in comparison with those of methanol extracts obtained by sonication. Therefore, these conditions could be applied for further extraction and isolation of phenolic compounds from lemon pomace.

The fruit of date palm tree Phoenix dactylifera is among the most abundant fruits, and it is rich in essential nutrients. Quality-wise, not all cultivated date fruits meet the commercial standards, and tons of date fruit that are immature, or of poor appearance but with no reduced nutritive value are treated as date by-product and are being used for animal feed or are discarded during processing by the relevant industries. Together with the rejected fruit, date seed which is the inedible part, and the trimmed fronds of the date palm, they are all discarded, resulting in an environmental problem, and an economical loss. The objective of this review is to identify current practices on the uses of low-grade date, seed, and frond in the industry. The literature shows date fruit of low quality is typically processed to make date paste and date syrup, and both are well utilized in the food sector. The chemical composition of date seed, and increasingly of other parts are well known, and fully exploited in many industrial applications.

Simple Summary The profiles of miRNAs, tRNA-derived fragments and tRNAs from lung cancer biopsy specimens indicate involvement of gene networks that modulate signaling and translation initiation. The current study highlights the important role of several regulatory small non-coding RNAs in aberrant signaling and translation deregulation in lung cancer. Abstract Transcriptomics profiles of miRNAs, tRNAs or tRFs are used as biomarkers, after separate examination of several cancer cell lines, blood samples or biopsies. However, the possible contribution of all three profiles on oncogenic signaling and translation as a net regulatory effect, is under investigation. The present analysis of miRNAs and tRFs from lung cancer biopsies indicated putative targets, which belong to gene networks involved in cell proliferation, transcription and translation regulation. In addition, we observed differential expression of specific tRNAs along with several tRNA-related genes with possible involvement in carcinogenesis. Transfection of lung adenocarcinoma cells with two identified tRFs and subsequent NGS analysis indicated gene targets that mediate signaling and translation regulation. Broader analysis of all major signaling and translation factors in several biopsy specimens revealed a crosstalk between the PI3K/AKT and MAPK pathways and downstream activation of eIF4E and eEF2. Subsequent polysome profile analysis and 48S pre-initiation reconstitution experiments showed increased global translation rates and indicated that aberrant expression patterns of translation initiation factors could contribute to elevated protein synthesis. Overall, our results outline the modulatory effects that possibly correlate the expression of important regulatory non-coding RNAs with aberrant signaling and translation deregulation in lung cancer.

Microbial exopolysaccharide (EPS) is of interest due to their applications in food processing and potential health benefits following consumption. The objectives of this study were to: 1) isolate, purify and characterize EPS produced by Enterococcus faecium MS79 (EPS-MS79); 2) investigate bioactive properties of EPS-MS79; and 3) investigate the rheological properties of the EPS-MS79 as influenced by salt type and pH level. The average molecular weight of the EPS-MS79 was 8.3 × 105 Da and it is composed of the three monosaccharides arabinose, mannose, and glucose in a molar ratio of 0.8:1.7:11.3. Scavenging activities of EPS-MS79 were 76% and 85% as measured by DPPH and 26% and 44% as measured by ABTS. The antiproliferative activities against colon (72% and 77%) and breast (43% and 56%) cancer cell lines. EPS-MS79 inhibited the growth of bacterial pathogens by up to 3 logs compared to the control. All EPS-MS79 solutions displayed shear thinning behavior. The storage and loss moduli of all EPS-MS79 solutions increased alongside with the frequency increase. Salt type and pH level impacted on the rheological properties of EPS-MS79. The EPS-MS79 could be a potent prebiotic promoting health and rheological properties of foods.