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In infected cells, Epstein–Barr virus (EBV) alternates between latency and lytic replication. The viral bZIP transcription factor ZEBRA (Zta, BZLF1) regulates this cycle by binding to two classes of ZEBRA response elements (ZREs): CpG-free motifs resembling the consensus AP-1 site recognized by cellular bZIP proteins and CpG-containing motifs that are selectively bound by ZEBRA upon cytosine methylation. We report structural and mutational analysis of ZEBRA bound to a CpG-methylated ZRE (meZRE) from a viral lytic promoter. ZEBRA recognizes the CpG methylation marks through a ZEBRA-specific serine and a methylcytosine-arginine-guanine triad resembling that found in canonical methyl-CpG binding proteins. ZEBRA preferentially binds the meZRE over the AP-1 site but mutating the ZEBRA-specific serine to alanine inverts this selectivity and abrogates viral replication. Our findings elucidate a DNA methylation-dependent switch in ZEBRA’s transactivation function that enables ZEBRA to bind AP-1 sites and promote viral latency early during infection and subsequently, under appropriate conditions, to trigger EBV lytic replication by binding meZREs.

To contribute to a better understanding of consumer food leftovers and to facilitate their reduction in out-of-home settings, our study analyzes the effects of two common intervention strategies for reducing leftovers in a holistic behavioral model. Based on a quasi-experimental baseline-intervention design, we analyzed how the display of information posters and the reduction of portion sizes take an effect on personal, social and environmental determinants in a structural equation model. Applying data from online surveys and observations among 880 guests (503 baseline, 377 intervention) during two weeks in a university canteen, the suggested model allows to assign effects from the two interventions on plate leftovers to specific changes in behavioral determinants. Portion size reductions for target dishes are found to relate to lower levels of plate waste based on conscious perception, represented in smaller portion size ratings. Effects from seeing information posters are found to base on changed personal attitudes, subjective norms and perceived behavioral control. However, depending on how an individual reacts to the information (by only making an effort to finish all food or by making an effort and additionally choosing a different dish in the canteen) there are opposite effects on these determinants and consequently also on plate leftovers. Overall, the differentiated results on intervention effects strongly support the benefits of more holistic and in-depth analyses of interventions to reduce plate leftovers and therefore to contribute to more sustainable food consumption in out-of-home settings.

In the last decade, in many European Countries more and more measures have been initiated aiming at the prevention of food losses and wastes along the entire value chain. In order to evaluate or monitor such important measures it is crucial to obtain quantitative information on generated food waste amounts, subsequently enabling the quantitative evaluation of the measure's outcomes and efficiency. Currently there is a paucity of quantitative information, particularly on food losses that are directly generated during harvesting processes. Up to date, no method is available or standardised aiming at the in-situ or on-site quantification of food losses during harvest. Using the example of the potato harvest, this study presents a practical approach for determining potato losses. To test the applicability of the developed method, on-site measurements were conducted directly on the field at five different locations in Austria and Germany. Our method enables the quantification of food losses based on defined areas along the harvested potato rows, where the analyser manually collects potatoes during their harvest. Hereby, two types of potato losses needs to be considered: non-harvested, under-sized potatoes that remain under the earth and the harvested ones, which are rejected on-site because of quality requirements regarding their size, shape, and state of health. Our study shows that between 1 and 9% of field losses (based on yield potential) can be generated during the potato harvest. In future, this method may be the basis for standardised protocols in order to be able to derive cultivar-specific benchmarks and, consequently, to develop measures for preventing food losses. In general, more case studies and evidence-based ground-up measurements on other cultivars and for other regions are needed focusing on the on-site quantification of post-harvest losses.

Acute antiviral functions of all nucleated cells rely on type I interferon (IFN-I) pathways triggered upon viral infection. Host responses encompass the sensing of incoming viruses, the activation of specific transcription factors that induce the transcription of IFN-I genes, the secretion of different IFN-I types and their recognition by the heterodimeric IFN-α/β receptor, the subsequent activation of JAK/STAT signaling pathways, and, finally, the transcription of many IFN-stimulated genes (ISGs)., Epstein-Barr virus (EBV), a human herpesvirus, encodes 44 microRNAs (miRNAs), which regulate many genes with various functions in EBV-infected cells. Multiple target genes of the EBV miRNAs have been identified, some of which play important roles in adaptive antiviral immune responses. Using EBV mutant derivatives, we identified additional roles of viral miRNAs in governing versatile type I interferon (IFN) responses upon infection of human primary mature B cells. We also found that Epstein-Barr virus-encoded small RNAs (EBERs) and LF2, viral genes with previously reported functions in inducing or regulating IFN-I pathways, had negligible or even contrary effects on secreted IFN-α in our model. Data mining and Ago PAR-CLIP experiments uncovered more than a dozen previously uncharacterized, direct cellular targets of EBV miRNA associated with type I IFN pathways. We also identified indirect targets of EBV miRNAs in B cells, such as TRL7 and TLR9, in the prelatent phase of infection. The presence of epigenetically naive, non-CpG methylated viral DNA was essential to induce IFN-α secretion during EBV infection in a TLR9-dependent manner. In a newly established fusion assay, we verified that EBV virions enter a subset of plasmacytoid dendritic cells (pDCs) and determined that these infected pDCs are the primary producers of IFN-α in EBV-infected peripheral blood mononuclear cells. Our findings document that many EBV-encoded miRNAs regulate type I IFN response in newly EBV infected primary human B cells in the prelatent phase of infection and dampen the acute release of IFN-α in pDCs upon their encounter with EBV.

Mammalian cells release different types of vesicles, collectively termed extracellular vesicles (EVs). EVs contain cellular microRNAs (miRNAs) with an apparent potential to deliver their miRNA cargo to recipient cells to affect the stability of individual mRNAs and the cells’ transcriptome. The extent to which miRNAs are exported via the EV route and whether they contribute to cell-cell communication are controversial. To address these issues, we analyzed the capacity of EVs to deliver packaged miRNAs into target cells and to exert biological functions. We applied well-defined approaches to produce and characterize purified EVs with or without specific viral miRNAs. We found that only a small fraction of EVs carried miRNAs. EVs readily bound to different target cell types, but there was no EV-cell membrane fusion or delivery of cargo. Importantly, the functionality of cells exposed to miRNA-carrying EVs was not affected. These results suggest EV-borne miRNAs do not act as effectors and question their relevancy in paracrine cell-to-cell communication.AUTHOR SUMMARYThe majority of metazoan cells release vesicles of different types and origins, such as exosomes and microvesicles, now collectively termed extracellular vesicles (EVs). EVs have gained much attention because they contain microRNAs (miRNAs) and thus could regulate their specific mRNA targets in recipient or acceptor cells that take up EVs. Using a novel fusion assay with superior sensitivity and specificity, we revisited this claim but found no convincing evidence for an efficient functional uptake of EVs in many different cell lines and primary human blood cells. Even EVs engineered to fuse and deliver their miRNA cargo to recipient cells had no measurable effect on target mRNAs in very carefully controlled, quantitative experiments. Our negative results clearly indicate that EVs do not act as vehicles for miRNA-based cell-to-cell communication.

There is broad consensus that the amount of food produced for human nutrition but not finally consumed is one of the great challenges societies have to meet in the pursuit of a more sustainable food system. Many recommendations have been published and disseminated to households recently in order to reduce household food waste. So far, there is no evidence that these suggestions are an effective toolbox consumers can apply to minimise their food waste. The purpose of this paper is to discover which kind of information or action is appropriate to minimise household food waste by presenting the results of a consumer survey with 351 respondents conducted in Germany in autumn 2011. Important findings are that the advice given so far does not address households' actual difficulties in minimising food waste but rather secondary issues and hence fails to reduce individual food waste. It becomes obvious that especially complex and irregular lifestyles as well as exceptional situations cause waste. Expired best before and use by dates are important to a lesser extent because the products wasted most frequently are not sold with such labels and consumers' comprehension of these labels is correct.

Food produced but not used for human consumption is a waste of natural resources. In order to prevent and reduce food waste, the main causes have to be identified systematically along the food supply chain (FSC). The aim of this study is (1) to shed light on the causes and effects of food waste through the analysis of 44 qualitative expert interviews examining the processes and intermediaries along the German food chain and (2) to find methods to reduce it. Results indicate that food waste occurs at all stages in the food chain. Thus, there is no single culprit to be blamed. Besides, the identified reasons for food waste differ between product groups, not a single solution can cause notable change. Furthermore, the analysis demonstrates that the causes and effects of food waste are to be found at different stages of the value chain. Hence, it is of high importance to improve communication and to raise a new appreciation for food among all stakeholders of the food supply chain in order to develop a more sustainable food system. Information on the topic of food waste needs to be shared among all actors of the supply chain. They need to share responsibility and work together to reduce food waste.

This article presents a marketing campaign guide to support nonprofit and governmental organizations, such as academic research institutes or governmental agencies, that wish to develop support tools for the food industry. It offers a systematic and target audience-centered approach which guides nonprofits through the various steps of a marketing campaign, from defining the required values of a new product or service to ultimately launching it. The text also explains how a target audience-centered marketing approach was applied in a case study of developing and transferring the LAV platform (LAV—Avoiding Food Waste, from the German “Lebensmittel Abfall Vermeiden”), a website that has been specifically set up and targeted to small- and medium-sized companies (SMEs) in the German food sector that wish to reduce food waste in their operations. Currently, there are more than 500 tools available in the English or German language which attempt to support companies in the food sector in their food waste reduction efforts. However, so far there has been no platform that could gather all these tools to facilitate SMEs’ access to them. The LAV platform compiles various relevant tools from academia as well as from industry and makes the most suitable tools available in a toolbox published on the Internet platform. Here, the tools are structured by topic and market segment; its user-friendliness was tested applying participatory methods which involved SMEs and industry organizations. The LAV platform, as well as target audience-centered marketing approaches more generally, could act as role models for other international projects that also have the goal of setting up and promoting tool-gathering systems.

Based on their experiences gained in 15 companies in the catering sector and the bakery industry, the authors present a participatory concept to reduce food waste in the food industry. This five-phase concept, adapted to the PDCA (Plan–Do–Check–Act) cycle applied in the Total Quality Management, involves a participatory approach where employees are integrated into the process of developing and implementing measures to counteract food waste. The authors describe how the participatory approach can be used to raise awareness of the topic of food waste to improve employee commitment and responsibility. As a result, the authors further offer a Manual for Managers wishing to reduce food waste in their respective organizations. This manual includes information on the methodologies applied in each step of the improvement cycle. It also describes why the steps are necessary, and how results can be documented. The participatory concept and the Manual for Managers contribute to reducing food waste and to enhancing resource efficiency in the food industry.

Nutrition is responsible for about 30% of global natural resource use. In order to limit the negative impact the nutritional sector has on the environment and on society, the consumption and processing of foodstuffs with assumed low negative impact is an important topic in the effort of sustainable development. In professional kitchens, clearly defined indicators assessing the impact of business activities are needed in this effort. The research and development in the NAHGAST project provides groundwork that could be of important assistance in this effort. Two versions of an assessment tool, with indicators of different complexity (NAHGAST Meal-Basic and NAHGAST Meal-Pro), were developed that can be used by kitchen professionals to determine the sustainability performance of their products - the offered meal. An informed selection of indicators, and a discussion of what processes and impacts this indicator relates to in the wider context, are essential and are discussed in this paper. Furthermore, in the selection of indicators for the purpose of our research certain criteria were considered simultaneously: (1) Communicability - What information an indicator can communicate and how comprehensible this information is for different actors; (2) Feasibility and data availability - Whether there is sufficient data for an indicator to be included and whether it is realistic for companies to integrate this indicator in their daily work practice; and (3) Scientific relevance - Whether the indicator is relevant for sustainability efforts on a larger scale and for related discussions in the scientific community. Insights related to these considerations are valuable for future developments in sustainability assessment in out-of-home gastronomy. The tool has been used to evaluate a number of dishes and results are deemed meaningful. However, assessments must not be understood as an accurate measurement but as an approximation of the sustainability of meals. At the level of individual indicators, they allow a detailed analysis and targeted optimization of recipes, while the aggregated results in the form of labels can be communicated well to customers. However, deficiencies and challenges, as discovered in the application phase of the project, demonstrate research gaps in the wider context. Finally, further steps for an integration of the tool in company processes and remaining options for companies to adjust the tool are discussed.

During the establishment of a bacterial infection, the surface molecules of the host organism are of particular importance, since they mediate the first contact with the pathogen. In Caenorhabditis elegans, mutations in the srf-3 locus confer resistance to infection by Microbacterium nematophilum, and they also prevent biofilm formation by Yersinia pseudotuberculosis, a close relative of the bubonic plague agent Yersinia pestis. We cloned srf-3 and found that it encodes a multitransmembrane hydrophobic protein resembling nucleotide sugar transporters of the Golgi apparatus membrane. srf-3 is exclusively expressed in secretory cells, consistent with its proposed function in cuticle/surface modification. We demonstrate that SRF-3 can function as a nucleotide sugar transporter in heterologous in vitro and in vivo systems. UDP-galactose and UDP-N-acetylglucosamine are substrates for SRF-3. We propose that the inability of Yersinia biofilms and M. nematophilum to adhere to the nematode cuticle is due to an altered glycoconjugate surface composition of the srf-3 mutant.

The DAF-2 insulin receptor-like signaling pathway controls metabolism, development, longevity, and stress response in C. elegans. Here we show that SGK-1, the C. elegans homolog of the serum- and glucocorticoid-inducible kinase SGK, acts in parallel to the AKT kinases to mediate DAF-2 signaling. Loss of sgk-1 results in defective egg-laying, extended generation time, increased stress resistance, and an extension of life span. SGK-1 forms a protein complex with the AKT kinases, and is activated by and strictly depends on PDK-1. All three kinases of this complex are able to directly phosphorylate DAF-16/FKHRL1, yet have different functions in DAF-2 signaling. Whereas AKT-1 and AKT-2 are more important for regulating dauer formation, SGK-1 is the crucial factor for the control of development, stress response, and longevity. Our data also suggest the existence of a second pathway from DAF-2 to DAF-16 that does not depend on AKT-1, AKT-2, and SGK-1.

Food losses occur across the whole food supply chain. They have negative effects on the economy and the environment, and they are not justifiable from an ethical point of view. The food service industry was identified by Beretta et al. (2013) as the third largest source of food waste based on food input at each stage of the value added chain. The total losses are estimated 18% of the food input, the avoidable losses 13.5%. However, these estimations are related with considerable uncertainty. To get more reliable and detailed data of food losses in this sector, the waste from two companies (in the education and business sectors) was classified into four categories (storage losses, preparation losses, serving losses, and plate waste) and seven food classes and measured for a period of five days. A ques- tionnaire evaluated customer reaction, and a material flow analysis was used to describe the mass and monetary losses within the process chain. The study found that in company A (education sector) 10.73% and in company B (business sector) 7.69% of the mass of all food delivered was wasted during the process chain. From this, 91.98% of the waste in company A and 78.14% in company B were classified as avoidable. The highest proportion of waste occurred from serving losses with starch accompaniments and vegetables being the most frequently wasted items. The quantities of waste per meal were 91.23 g (value CHF 0.74) and 85.86 g (value CHF 0.44) for company A and company B, respectively. The annual loss averaged 10.47 tonnes (value CHF 85,047) in company A and 16.55 tonnes (value CHF 85,169) in company B. The customer survey showed that 15.79% (n = 356) of the respondents in company A and 18.32% (n = 382) in company B produced plate waste. The main causes of plate waste cited were 'portion served by staff too large' and 'lack of hunger'. Sustainable measures need to be implemented in the food service industry to reduce food waste and to improve efficiency.

Epstein-Barr virus (EBV) is a human herpesvirus which has been studied intensively for its role in certain human tumors. It also serves as a model of herpesviral latency because it establishes an immediate, latent infection in human B cells. When EBV infects quiescent, primary B cells it induces their continuous proliferation to yield growth-transformed B-cell lines in vitro . The lytic or productive phase of EBV's life cycle is induced by the expression of the viral BZLF1 gene in latently infected cells. The BZLF1 protein is a transactivator, which selectively binds to two classes of distinct DNA sequence motifs. One class is similar to the motifs that are bound by members of the AP-1 transcription factor family to which BZLF1 belongs. The second class, which contains CpG motifs, is predominant in viral promoters of early lytic genes and is BZLF1's preferred or exclusive target sequence when methylated. The BZLF1 gene is transiently expressed in newly infected B cells but fails to induce EBV's lytic cycle, potentially because the virion DNA is unmethylated. Here we report that the lack of 5-methylcytosine residues in CpG sites of virion DNA prevents the expression of essential lytic genes indispensable for viral DNA amplification during productive infection. This finding indicates that BZLF1 transactivates these promoters in a methylation-dependent fashion and explains how progeny virus synthesis is abrogated in newly infected B cells. Our data also reveal that viral lytic DNA synthesis precludes CpG methylation of virion DNA during EBV's lytic, productive cycle, which can be overcome by the ectopic expression of a prokaryotic cytosine methyltransferase to yield CpG-methylated virion DNA. Upon infection of B cells, randomly CpG-methylated virion DNA induces high expression of essential lytic genes in contrast to virion DNA free of 5-methylcytosine residues. Our data suggest that unmethylated virion DNA is part of EBV's strategy to prevent the viral lytic phase in newly infected B cells, allowing it to establish its characteristic latent infection in them.

DNA methylation is the major modification of eukaryotic genomes and plays an essential role in mammalian gene regulation. In general, cytosine-phosphatidyl-guanosine (CpG)-methylated promoters are transcriptionally repressed and nuclear proteins such as MECP2, MBD1, MBD2, and MBD4 bind CpG-methylated DNA and contribute to epigenetic silencing. Methylation of viral DNA also regulates gene expression of Epstein-Barr virus (EBV), which is a model of herpes virus latency. In latently infected human B cells, the viral DNA is CpG-methylated, the majority of viral genes is repressed and virus synthesis is therefore abrogated. EBV's BZLF1 encodes a transcription factor of the AP-1 family (Zta) and is the master gene to overcome viral gene repression. In a genome-wide screen, we now identify and characterize those viral genes, which Zta regulates. Among them are genes essential for EBV's lytic phase, which paradoxically depend on strictly CpG-methylated promoters for their Zta-induced expression. We identified novel DNA recognition motifs, termed meZRE (methyl-Zta-responsive element), which Zta selectively binds in order to ‘read’ DNA in a methylation- and sequence-dependent manner unlike any other known protein. Zta is a homodimer but its binding characteristics to meZREs suggest a sequential, non-palindromic and bipartite DNA recognition element, which confers superior DNA binding compared to CpG-free ZREs. Our findings indicate that Zta has evolved to transactivate cytosine-methylated, hence repressed, silent promoters as a rule to overcome epigenetic silencing., Author Summary Epstein-Barr virus (EBV) is a model of human tumor viruses and viral latency. We have found previously that (i) EBV DNA is unmethylated upon infection, but becomes methylated over time by the host B cell, and (ii) the BZLF1-encoded protein, Zta (a cousin to AP-1), induces the viral lytic cycle, but it prefers binding sites that are CpG-methylated. As a consequence, the lytic phase gets delayed until enough methylation of viral DNA has occurred. The molecular basis of this mechanism has not been addressed but in a genome-wide screen, we now identify and characterize those viral genes, which Zta regulates. Among them are genes essential for EBV's lytic phase, which paradoxically depend on strictly CpG-methylated promoters for their Zta-induced expression. Our findings indicate that Zta has evolved to transactivate cytosine-methylated, hence repressed, silent promoters as a rule to overcome epigenetic silencing. In this way, the EBV virus has created its own time-dependent, epigenetic switch to control its biphasic life cycle.

Mutations in presenilin genes are associated with familial Alzheimer's disease in humans and affect LIN-12/Notch signaling in all organisms tested so far. Loss of sel-12 presenilin activity in Caenorhabditis elegans results in a completely penetrant egg-laying defect. In screens for extragenic suppressors of the sel-12 egg-laying defect, we have isolated mutations in at least five genes. We report the cloning and characterization of spr-3 and spr-4, which encode large basic C2H2 zinc-finger proteins. Suppression of sel-12 by spr-3 and spr-4 requires the activity of the second presenilin gene, hop-1. Mutations in both spr-3and spr-4 de-repress hop-1 transcription in the early larval stages when hop-1 expression is normally nearly undetectable. As sel-12 and hop-1 are functionally redundant, this suggests that mutations in spr-3 and spr-4 bypass the need for one presenilin by stage-specifically de-repressing the transcription of the other. Both spr-3 and spr-4 code for proteins similar to the human REST/NRSF (Re1 silencing transcription factor/neural-restrictive silencing factor) transcriptional repressors. As other Spr genes encode proteins homologous to components of the CoREST co-repressor complex that interacts with REST, and the INHAT (inhibitor of acetyltransferase) co-repressor complex, our data suggest that all Spr genes may function through the same mechanism that involves transcriptional repression of the hop-1locus.