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Simple Summary: African swine fever has widely spread in China in the last couple of years and posed a significant impact on pig industry. Currently, there is no safe and effective commercial vaccine available and the prevention and control of the disease mainly rely on the early detection and stamping out strategy. Therefore, it is important to develop a specific and easy for use method for diagnosis of this disease. In this study, we generated two specific monoclonal antibodies against the capsid protein p17 of African swine fever virus particles. Both monoclonal antibodies have been successfully applied in different immune assays including enzyme-linked immunosorbent assay, Western blotting assay and immunofluorescence assay. Moreover, both p17 monoclonal antibodies were found to recognize a new antigenic epitope of 72–78 amino acids of p17 protein, which it is identical across all genotype I and II strains of African swine fever virus. Based on this epitope peptide, an indirect ELISA has been established to effectively detect antibodies during virus infection, and it will significantly promote the serological diagnosis and contribute to the disease prevention and control. African swine fever (ASF) has widely spread around the world in the last 100 years since its discovery. The African swine fever virus (ASFV) particles are made of more than 150 proteins, with the p17 protein encoded by the D117L gene serving as one of the major capsid proteins and playing a crucial role in the virus's morphogenesis and immune evasion. Thus, monoclonal antibody (mAb) targeting p17 is important for the research and detection of ASFV infection. Here, we produced two specific mAbs against p17, designated as 1G2 and 6G3, respectively, and both have been successfully used in enzyme-linked immunosorbent assay (ELISA), Western blotting, and immunofluorescence assay. Moreover, we found that both 1G2 and 6G3 mAbs recognize a novel epitope of 72–78 amino acids of p17 protein, highly conserved across all genotype I and II strains. Based on this epitope, an indirect ELISA has been established to effectively detect antibodies during ASFV infection, and it exhibits high consistency with commercial ASFV ELISA kits. In summary, the production of the specific p17 mAbs and the identification of the recognized epitope will significantly promote the serological diagnosis of ASFV. [ABSTRACT FROM AUTHOR]

To explore whether the p17 protein of oncolytic avian reovirus (ARV) mediates cell migration and invadopodia formation, we applied several molecular biological approaches for studying the involved cellular factors and signal pathways. We found that ARV p17 activates the p53/phosphatase and tensin homolog (PTEN) pathway to suppress the focal adhesion kinase (FAK)/Src signaling and downstream signal molecules, thus inhibiting cell migration and the formation of invadopodia in murine melanoma cancer cell line (B16-F10). Importantly, p17-induced formation of invadopodia could be reversed in cells transfected with the mutant PTENC124A. p17 protein was found to significantly reduce the expression levels of tyrosine kinase substrate 5 (TKs5), Rab40b, non-catalytic region of tyrosine kinase adaptor protein 1 (NCK1), and matrix metalloproteinases (MMP9), suggesting that TKs5 and Rab40b were transcriptionally downregulated by p17. Furthermore, we found that p17 suppresses the formation of the TKs5/NCK1 complex. Coexpression of TKs5 and Rab40b in B16-F10 cancer cells reversed p17-modulated suppression of the formation of invadopodia. This work provides new insights into p17-modulated suppression of invadopodia formation by activating the p53/PTEN pathway, suppressing the FAK/Src pathway, and inhibiting the formation of the TKs5/NCK1 complex. [ABSTRACT FROM AUTHOR]

African swine fever virus (ASFV) is notoriously known for evolving strategies to modulate IFN signaling. Despite lots of efforts, the underlying mechanisms have remained incompletely understood. This study concerns the regulatory role of viral inner membrane protein p17. We found that the ASFV p17 shows a preferential interaction with cGAS-STING-IRF3 pathway, but not the RIG-IMAVS-NF-κB signaling, and can inhibit both poly(I:C)- and poly(A:T)-induced activation of IRF3, leading to attenuation of IFN-β induction. Mechanistically, p17 interacts with STING and IRF3 and recruits host scaffold protein PR65A, a subunit of cellular phosphatase PP2A, to down-regulate the level of p-IRF3. Also, p17 targets STING for partial degradation via induction of cellular apoptosis that consequently inhibits activation of both p-TBK1 and p-IRF3. Thus, our findings reveal novel regulatory mechanisms for p17 modulation of IFN signaling and shed light on the intricate interplay between ASFV proteins and host immunity. [ABSTRACT FROM AUTHOR]

African swine fever (ASF) has widely spread around the world in the last 100 years since its discovery. The African swine fever virus (ASFV) particles are made of more than 150 proteins, with the p17 protein encoded by the D117L gene serving as one of the major capsid proteins and playing a crucial role in the virus’s morphogenesis and immune evasion. Thus, monoclonal antibody (mAb) targeting p17 is important for the research and detection of ASFV infection. Here, we produced two specific mAbs against p17, designated as 1G2 and 6G3, respectively, and both have been successfully used in enzyme-linked immunosorbent assay (ELISA), Western blotting, and immunofluorescence assay. Moreover, we found that both 1G2 and 6G3 mAbs recognize a novel epitope of 72–78 amino acids of p17 protein, highly conserved across all genotype I and II strains. Based on this epitope, an indirect ELISA has been established to effectively detect antibodies during ASFV infection, and it exhibits high consistency with commercial ASFV ELISA kits. In summary, the production of the specific p17 mAbs and the identification of the recognized epitope will significantly promote the serological diagnosis of ASFV.

ABSTRACT: Avian reovirus (ARV), which commonly induces viral arthritis or tenosynovitis and immunosuppression in chickens, is associated with the nonstructural protein p17 that plays a crucial role in viral replication and regulates cellular signaling pathways through its interaction with cellular proteins. In our previous study, we identified the host protein IFN-γ-inducible protein-16 (IFI16) as an interacting partner of ARV p17 through yeast two-hybrid screening. In the current study, we further confirmed the interaction between IFI16 and p17 protein using coimmunoprecipitation, glutathione S-transferase (GST)-pulldown assay, and laser confocal microscopy techniques. Additionally, we found that the amino acid of p1761-119 is responsible for mediating the interaction with the HINa and HINb domains of IFI16. Interestingly, we observed a significant increase in IFI16 expression upon ARV infection or p17 protein exposure. Moreover, the replication of ARV was found to be largely influenced by the quantity of IFI16 protein. Overexpression of IFI16 led to a significant decrease in ARV replication, while knockdown of the IFI16 expression led to the contrary result. Additionally, our findings demonstrate that IFI16 plays a crucial role in the induction of inflammatory cytokines IFN-β and IL-1β during ARV infection as confirmed by qRT-PCR and ELISA analyses. In conclusion, our study provides novel insights into the functional role of p17 protein and the pathogenic mechanism underlying ARV infection, particularly its association with inflammatory response. Furthermore, it offers new perspectives for identifying potential therapeutic targets against ARV infection.

ABSTRACTViruses have developed different strategies to hijack mitophagy to facilitate their replication. However, whether and how African swine fever virus (ASFV) regulates mitophagy are largely unknown. Here, we found that the ASFV-encoded p17 induced mitophagy. Coimmunoprecipitation/mass spectrometry assays identified translocase of outer mitochondrial membrane 70 (TOMM70) as the protein that interacted with p17. The binding of TOMM70 to p17 promoted the binding of the mitophagy receptor SQSTM1 to TOMM70, led to engulfment of mitochondria by autophagosomes, and consequently decreased the number of mitochondria. Consistently, the levels of TOMM70 and TOMM20 decreased substantially after p17 expression or ASFV infection. Furthermore, p17-mediated mitophagy resulted in the degradation of mitochondrial antiviral signalling proteins and inhibited the production of IFN-α, IL-6 and TNFα. Overall, our findings suggest that ASFV p17 regulates innate immunity by inducing mitophagy via the interaction of SQSTM1 with TOMM70.

As a highly pathogenic large DNA virus, African swine fever virus (ASFV) has huge particles and numerous encoded proteins. At present, few of the existing studies on ASFV proteins have investigated the function of p17. Specific antibodies against p17 to promote the development of prevention techniques against African swine fever (ASF) are urgently needed. Herein, we successfully expressed ASFV p17 in CHO cells using a suspension culture system and generated a monoclonal antibody (mAb) against p17. The mAb recognized a novel linear epitope (8LLSHNLSTREGIK20) and exhibited specific reactivity, which was conducive to the identification of ectopically expressed p17, the recombinant porcine reproductive and respiratory syndrome virus expressing p17, and the ASFV-SY18. The epitope was conservative among genotype I and genotype II ASFV strains. Overall, the mAb against p17 revealed efficient detection and promising application prospects, making it a useful tool for future vaccine research on ASF. Determination of the conserved linear epitope of p17 would contribute to the in-depth exploration of the biological function of ASFV antigen protein.

The Logistics Performance Index (LPI) performed by the World Bank is an indicator of the logistics environment quality of a country in which logistics operators act. The LPI is an interactive tool designed to help countries identify challenges, innovative solutions, and opportunities they face in their work in the field of trade and logistics. The aim of this paper is to conduct a comparative analysis and ranking of the LPI of the countries in the Western Balkans (Bosnia and Herzegovina, North Macedonia, Albania, Serbia and Montenegro), calculated by the World Bank for 2018, using an integrated Criteria Importance Through Intercriteria Correlation (CRITIC)-Measurement Alternatives and Ranking according to Compromise Solution (MARCOS) model and thus show the real picture of the logistics environment. In order to determine the performance of countries and show the overall logistics performance, six key dimensions are used: customs, infrastructure, international transport, logistics capability, tracking and tracing of goods and shipment delivery within scheduled or expected times. Using the CRITIC method, the weight values of the previously mentioned six criteria were calculated, whereby the criterion related to shipment delivery within scheduled times was singled out as the most significant criterion. Then, by applying the MARCOS method, the countries of the Western Balkans were ranked on the basis of the six defined criteria. Based on the results obtained, the best-ranked country is Serbia. The analysis of the sensitivity of the results to changes in the significance of the criteria does not show significant changes in the ranking.

Today, together with the recognition of the tourism industry as one of the priorities in the economy of Ukraine, quite active and effective activities have been launched to build a structure of prerequisites for achieving the most effective level of its functioning. At the same time, we understand that to achieve the most successful functioning of the market of tourist services, it is necessary to initiate efforts to overcome the economic crisis and stop military events in Ukraine. We can witness that the market of needs services is becoming increasingly important as a mandatory component in the languages of modern market relations. The tourism industry is a leading field of activity in many countries worldwide. Its development allows you to actively use the most popular and valuable natural resources, ensure job creation, significantly improve the economic, environmental, and social situation, and expand investment space. In Ukraine, the sphere of tourist services has not yet taken its rightful place in services and the economy in general. Therefore, there is a need to substantiate various processes implemented in tourism services at the scientific level, with due regard for national and regional market realities, both in the market and its economic and social situation. An important aspect is also the socio-economic development of the state’s regions, which reflects the continuity and stability of regional tourism markets. Among the many problems facing the balanced development of regional tourism, markets ensure the appropriate level of their competitiveness, both between each other and internationally. In our country, tourism began to gain its development at the whole level not so long ago because it did not have a total base for its formation. At the same time, forming a significant share of state, regional, and local budgets and being a necessary “plane” of market circulation, problems in regulating tourism in the regions are the focus of research while forming further and important competing principles. Therefore, today, we need to implement our study by rating the indicators of infrastructural development of the Western regional market of tourist services in Ukraine.

Avian reoviruses (ARV) are a group of poultry pathogens that cause runting and stunting syndrome (RSS), a condition otherwise known as "frozen chicken", which are characterized by dramatically delayed growth in broilers. It has been known that p17, a nonstructural protein encoded by ARV, prohibits cellular proliferation by halting the cell cycle at the G2/M phase, the result of which is directly associated with the typical clinical sign of RSS. Nevertheless, the mechanism by which p17 modulates cell-cycle progression remains largely unknown. Here, we screened the interactome of ectopically expressed p17 through a yeast two-hybrid assay and identified Bub3, a cellular mitotic checkpoint protein, as a binding partner of p17. The infection of the Vero cells by ARV downregulated the Bub3 expression, while the knockdown of Bub3 alleviated the p17-modulated cell-cycle arrest during ARV infection. Remarkably, the suppression of Bub3 by RNAi in the Vero cells significantly reduced the viral mRNA and protein abundance, which eventually led to diminished virus replication. Altogether, our findings reveal that ARV p17 impedes host cell proliferation through a Bub3-dependent cell-cycle arrest, which eventually contributes to efficient virus replication. These results also unveil a hitherto unknown therapeutic target for RSS. [ABSTRACT FROM AUTHOR]

The mechanism by which avian reovirus (ARV)-modulated suppression of mTORC1 triggers autophagy remains largely unknown. In this work, we determined that p17 functions as a negative regulator of mTORC1. This study suggest novel mechanisms whereby p17-modulated inhibition of mTORC1 occurs via upregulation of p53, inactivation of Akt, and enhancement of binding of the endogenous mTORC1 inhibitors (PRAS40, FKBP38, and FKPP12) to mTORC1 to disrupt its assembly and accumulation on lysosomes. p17-modulated inhibition of Akt leads to activation of the downstream targets PRAS40 and TSC2, which results in mTORC1 inhibition, thereby triggering autophagy and translation shutoff, which is favorable for virus replication. p17 impairs the interaction of mTORC1 with its activator Rheb, which promotes FKBP38 interaction with mTORC1. It is worth noting that p17 activates ULK1 and Beclin1 and increases the formation of the Beclin 1/class III PI3K complex. These effects could be reversed in the presence of insulin or depletion of p53. Furthermore, we found that p17 induces autophagy in cancer cell lines by upregulating the p53/PTEN pathway, which inactivates Akt and mTORC1. This study highlights p17-modulated inhibition of Akt and mTORC1, which triggers autophagy and translation shutoff by positively modulating the tumor suppressors p53 and TSC2 and endogenous mTORC1 inhibitors. [ABSTRACT FROM AUTHOR]

African swine fever virus (ASFV) infection causes African swine fever (ASF), a highly contagious and fatal disease that poses severe threat to swine production. To gain insights into the host responses to ASFV, we generated recombinant adenovirus Ad5 expressing viral membrane proteins p54, p17, and pB117L individually and infected an alveolar cell line, 3D4/21, with these recombinant viruses. Then, the cell lysates were analyzed using label-free quantification proteomic analysis method. A total of 2158 differentially expressed proteins (DEPs) were identified, of which 817, 466, and 875 proteins were from Ad5-p54-, Ad5-p17-, Ad5-pB117L-infected 3D4/21 cells, respectively. Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis revealed distinct yet interconnecting patterns of protein interaction networks. Specifically, the Ad5-p54 virus infection enriched the DEPs primarily involved in the metabolic pathways, endocytosis, adherens junction, and SNARE interactions in vesicular transport. The Ad5-p17 virus infection enriched the DEPs in endocytosis, ubiquitin-mediated proteolysis, N-Glycan biosynthesis, and apoptosis, while the Ad5-pB117L virus infection enriched the DEPs in metabolic pathways, endocytosis, oxidative phosphorylation, and focal adhesion. In summary, these results provide a comprehensive proteinomics analysis of the cellular responses to three ASFV membrane proteins, thus facilitating our understanding of ASFV pathogenesis. [ABSTRACT FROM AUTHOR]

The presence of women on boards of directors has become a social and economic demand. The relation between their presence on the board of directors and improved firm performance has already been studied. This paper aims to shed light on this topic by providing the first test as to how the level of innovation in the company may moderate this relationship. Our results, for a panel data of 231 European listed firms and based on GMM analysis, show that a critical mass of women positively affects firm performance, and that this effect increases as the firm’s innovation activity increases. We situate the analysis in the outset of the gender revolution in the Western countries to understand the nature of the gender equality process. [ABSTRACT FROM AUTHOR]

The post-2008 slowdown in economic convergence by countries of east central Europe towards the level of western Europe is interpreted with the help of a concept of dependent capitalism. Convergence appeared to be rapid up to that year, but then stalled, albeit with differing results depending on the measure used. Dependent capitalism meant that the driver for economic growth comes from inward investment by multinational companies (MNCs). Domestically owned businesses failed when faced with international competition, and their agenda hampers policies supporting an active role from the state. Inward investment is attracted by low wages and has contributed to substantial growth, but the slowdown in investment was accompanied by much slower economic growth and dangers that past investment could turn into a burden on the external balance. The strategies pursued by incoming MNCs have brought areas of upgrading, but frequently leave technological levels somewhat behind those of western Europe. Even where they use the same technologies as in their home countries, wages still remain significantly lower. Achieving full convergence would require a different growth model following a substantial change in economic policies: this does not appear likely in the near future.

The paper analyzes the institutional architecture and the effects of product market competition in 11 countries of Central and Eastern Europe (CEE). The aim of the research was to find out how similar or dissimilar are the CEE countries in the area of product market competition compared with the four models of capitalism prevailing in Western Europe: the Anglo-Saxon (liberal) model (the UK), the continental model (Germany), the Scandinavian (Nordic) model (Sweden), and the Mediterranean one (Spain). The research method involves calculations of the coefficients of similarity and the analysis of polygons, being the extension of our own concept of the hexagons of similarity. The dynamic approach adopted in this study allows to examine the path dependence in order to assess how the institutional environment evolved over time. The analysis indicates that almost all CEE countries were the most similar to the Mediterranean model of capitalism represented by Spain. However, the variety of results for the individual variables is also a proof that the model of capitalism prevailing in CEE in the area of product market competition may be called a patchwork capitalism.

How are markets possible under conditions of anonymity and lack of repeat dealing? Many scholars consider the problem of fraud as one that must be dealt with by law, but electronic commerce firms treat the problem of online fraud as a business problem, a problem of risk management. This article documents how merchants and financial intermediaries treat fraud as a cost that can be quantified and then minimized. Just as entrepreneurs earn profits by helping meet a previously unmet market demand, entrepreneurs earn profits by helping reduce what could have been considered an unsolved legal problem. Firms have profited by using predictive analytics and various if-then algorithms to help mitigate what might otherwise be an intractable problem and help vastly expand the scope of commerce. [ABSTRACT FROM AUTHOR]

The EU has many supranational accomplishments to its credit. Frictions nonetheless exist within the EU because some members want to rollback parts of the consensus (“less Europe”) and others want to expand them (“more Europe”). The conflict cannot be amicably resolved as EU leaders are trying to do in a one-track supranational regime because both factions disagree about whether confederation or federation is best. A solution in a one-track system requires one side to capitulate to the other. This is why the EU is at an impasse. However, the conflict is easily resolved by switching from a one-track to a multi-track supranational system that allows advocates of “more Europe” and “less Europe” to do as they like in some areas, while acting collectively wherever consensus permits. The EU already accepts the multi-track principle with regard to the euro and non-euro zones, and could restore harmony to the European project by applying the principle more broadly.

Toll-like receptors (TLRs) play a crucial role in innate immunity and provide a first line of host defense against invading pathogens. Of the identified human TLRs, TLR10 remains an orphan receptor whose ligands and functions are poorly understood. In the present study, we sought to evaluate the level of TLR10 expression in breast milk (BM) and explore its potential function in the context of HIV-1 infection. We evaluated HIV-1-infected (Nigerian: n = 40) and uninfected (Nigerian: n = 27; Canadian: n = 15) BM samples for TLR expression (i.e., TLR10, TLR2, and TLR1) and report here that HIV-1-infected BM from Nigerian women showed significantly higher levels of TLR10, TLR1, and TLR2 expression. Moreover, the level of TLR10 expression in HIV-1-infected BM was upregulated by over 100-fold compared to that from uninfected control women. In vitro studies using TZMbl cells demonstrated that TLR10 overexpression contributes to higher HIV-1 infection and proviral DNA integration. Conversely, TLR10 inhibition significantly decreased HIV-1 infection. Notably, HIV-1 gp41 was recognized as a TLR10 ligand, leading to the induction of IL-8 and NF-κBα activation. The identification of a TLR10 ligand and its involvement in HIV-1 infection enhances our current understanding of HIV-1 replication and may assist in the development of improved future therapeutic strategies.

Avian reovirus (ARV) p17 protein continuously shuttles between the nucleus and the cytoplasm via transcription-dependent and chromosome region maintenance 1 (CRM1)-independent mechanisms. Nevertheless, whether cellular proteins modulate nucleocytoplasmic shuttling of p17 remains unknown. This is the first report that heterogeneous nuclear ribonucleoprotein (hnRNP) A1 serves as a carrier protein to modulate nucleocytoplasmic shuttling of p17. Both in vitro and in vivo studies indicated that direct interaction of p17 with hnRNP A1 maps within the amino terminus (amino acids [aa] 19 to 40) of p17 and the Gly-rich region of the C terminus of hnRNP A1. Furthermore, our results reveal that the formation of p17-hnRNP A1-transportin 1 carrier-cargo complex is required to modulate p17 nuclear import. Utilizing sequence and mutagenesis analyses, we have identified nuclear export signal (NES) 19LSLRELAI26 of p17. Mutations of these residues causes a nuclear retention of p17. In this work, we uncovered that the N-terminal 21 amino acids (aa 19 to 40) of p17 that comprise the NES can modulate both p17 and hnRNP A1 interaction and nucleocytoplasmic shuttling of p17. In this work, the interaction site of p17 with lamin A/C was mapped within the amino terminus (aa 41 to 60) of p17 and p17 colocalized with lamin A/C at the nuclear envelope. Knockdown of hnRNP A1 or lamin A/C led to inhibition of nucleocytoplasmic shuttling of p17 and reduced virus yield. Collectively, the results of this study provide mechanistic insights into hnRNP A1 and lamin A/C-modulated nucleocytoplasmic shuttling of the ARV p17 protein. [ABSTRACT FROM AUTHOR]

Despite antiretroviral therapy, HIV+ individuals still have increased risk to develop lymphomas, including marginal zone lymphomas, suggesting that factors other than HIV-related immunosuppression are probably acting as lymphomagenic factors in the HIV setting. The possible pathogenic involvement of HIV p17 protein variants was investigated in a particularly informative case of HIV-related splenic marginal zone lymphoma, which was negative for oncogenic virus infections, thus allowing us to assess the possible direct contribution of these HIV-encoded proteins to lymphomagenesis. The presence of p17 protein was analyzed by immunohistochemistry in lymphoma tissue. Recombinant p17 protein derived from the dominant sequence detected in plasma and lymphoma biopsy was characterized for B-cell proliferation, clonogenicity in soft agar, in vitro tube formation and wound healing. Intracellular signaling was investigated by immunoblotting. HIV p17 protein was detected in reactive lymphoid follicles but not within lymphoma cells. An identical dominant variant p17 sequence, p17-Lyrm, carrying a 117 to 118 Ala-Ala insertion was detected in both plasma and lymphoma tissue. Recombinant p17-Lyrm enhanced B-cell proliferation and clonogenicity promoted the formation of capillary-like structures and enhanced endothelial cell migration. Unlike reference p17, the p17-Lyrm variant enhanced the activation of Akt and ERK, critical kinases in lymphomagenesis. p17-Lyrm clonogenic activity was dependent on the activation of Akt but not of ERK1/2. These results indicated that HIV p17 variants with distinct molecular signatures and functional properties may accumulate in lymphoid tissues of HIV-infected individuals where they may act as a local stimulus promoting the development of lymphomas. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) play a crucial role in innate immunity and provide a first line of host defense against invading pathogens. Of the identified human TLRs, TLR10 remains an orphan receptor whose ligands and functions are poorly understood. In the present study, we sought to evaluate the level of TLR10 expression in breast milk (BM) and explore its potential function in the context of HIV-1 infection. We evaluated HIV-1-infected (Nigerian: n = 40) and uninfected (Nigerian: n = 27; Canadian: n = 15) BM samples for TLR expression (i.e., TLR10, TLR2, and TLR1) and report here that HIV-1-infected BM from Nigerian women showed significantly higher levels of TLR10, TLR1, and TLR2 expression. Moreover, the level of TLR10 expression in HIV-1-infected BM was upregulated by over 100-fold compared to that from uninfected control women. In vitro studies using TZMbl cells demonstrated that TLR10 overexpression contributes to higher HIV-1 infection and proviral DNA integration. Conversely, TLR10 inhibition significantly decreased HIV-1 infection. Notably, HIV-1 gp41 was recognized as a TLR10 ligand, leading to the induction of IL-8 and NF-κBα activation. The identification of a TLR10 ligand and its involvement in HIV-1 infection enhances our current understanding of HIV-1 replication and may assist in the development of improved future therapeutic strategies. [ABSTRACT FROM AUTHOR]