5 research outputs found
Resolution of R-loops by INO80 promotes DNA replication and maintains cancer cell proliferation and viability
Collisions between the DNA replication machinery and co-transcriptional R-loops can impede DNA synthesis and are a major source of genomic instability in cancer cells. How cancer cells deal with R-loops to proliferate is poorly understood. Here we show that the ATP-dependent chromatin remodelling INO80 complex promotes resolution of R-loops to prevent replication-associated DNA damage in cancer cells. Depletion of INO80 in prostate cancer PC3 cells leads to increased R-loops. Overexpression of the RNA:DNA endonuclease RNAse H1 rescues the DNA synthesis defects and suppresses DNA damage caused by INO80 depletion. R-loops co-localize with and promote recruitment of INO80 to chromatin. Artificial tethering of INO80 to a LacO locus enabled turnover of R-loopsĀ in cis. Finally, counteracting R-loops by INO80 promotes proliferation and averts DNA damage-induced death in cancer cells. Our work suggests that INO80-dependent resolution of R-loops promotes DNA replication in the presence of transcription, thus enabling unlimited proliferation in cancers
Interferon-<b>Ī³</b> as a Potential Inhibitor of SARS-CoV-2 ORF6 Accessory Protein
The ORF6 protein of the SARS-CoV-2 virus plays a crucial role in blocking the innate immune response of the infected cells by inhibiting interferon pathways. Additionally, it binds to and immobilises the RAE1 protein on the cytoplasmic membranes, thereby blocking mRNA transport from the nucleus to the cytoplasm. In all these cases, the host cell proteins are tethered by the flexible C-terminus of ORF6. A possible strategy to inhibit the biological activity of ORF6 is to bind its C-terminus with suitable ligands. Our in silico experiments suggest that hIFNĪ³ binds the ORF6 protein with high affinity, thus impairing its interactions with RAE1 and, consequently, its activity in viral invasion. The in vitro studies reported here reveal a shift of the localisation of RAE1 in ORF6 overexpressing cells upon treatment with hIFNĪ³ from predominantly cytoplasmic to mainly nuclear, resulting in the restoration of the export of mRNA from the nucleus. We also explored the expression of GFP in transfected-with-ORF6 cells by means of fluorescence microscopy and qRT-PCR, finding that treatment with hIFNĪ³ unblocks the mRNA trafficking and reinstates the GFP expression level. The ability of the cytokine to block ORF6 is also reflected in minimising its negative effects on DNA replication by reducing accumulated RNA-DNA hybrids. Our results, therefore, suggest hIFNĪ³ as a promising inhibitor of the most toxic SARS-CoV-2 protein
Economic Integration of Urban Consumersā Demand and Forestry Production in Bulgaria
The objective of the paper is to contribute to a better understanding of the problems of economic integration of urban consumersā demand and rural forestry production and possible solutions of forest-based entrepreneurship in small-scale forestry, wood processing and non-wood forest products and services in Bulgaria. The paper presents some results of the work undertaken in the frame of the first phase of the European project COST Action E30 āEconomic integration of urban consumersā demand and rural forestry productionā. The presented five topics concern consumption of forest related products and services, small-scale forestry practices as a factor affecting consumption and living standards in the country, wood-processing industries, non-wood forest products and services, as well as forests resources and their ownership structure as factors, affecting forestry production. It has been assumed the economic integration of urban internal and external consumersā demand and forestry production in Bulgaria has to be developed. It is concluded that Bulgaria has significant resources and potential for further forestry production, which are not used effectively. The identified main barriers to entrepreneurship in the forestry, wood processing and non-wood products and services in Bulgaria are the low level of production and demand for forest ā wood product services, and respective national policy. The lack of consensus for enterprise development in the forestry in Bulgaria defines a broad area of questions to be answered. Among them are which model for innovation system in forestry to be chosen? Which is the effective strategy for further integration to EU forestry structures, what kind of effective marketing strategies for Bulgarian products to develop in order to increase foreign consumersādemand? What kind of instruments to be introduced in order to increase sources for purchasing modern forest machinery, building forest roads and forestation? What kind of incentives to be implemented to improve the quality of local production and to protect industrial property rights? How to speed processes of standardization and certification?
Molecular Mechanism of the Anti-Inflammatory Action of Heparin
Our objective is to reveal the molecular mechanism of the anti-inflammatory action of low-molecular-weight heparin (LMWH) based on its influence on the activity of two key cytokines, IFNĪ³ and IL-6. The mechanism of heparin binding to IFNĪ³ and IL-6 and the resulting inhibition of their activity were studied by means of extensive molecular-dynamics simulations. The effect of LMWH on IFNĪ³ signalling inside stimulated WISH cells was investigated by measuring its antiproliferative activity and the translocation of phosphorylated STAT1 in the nucleus. We found that LMWH binds with high affinity to IFNĪ³ and is able to fully inhibit the interaction with its cellular receptor. It also influences the biological activity of IL-6 by binding to either IL-6 or IL-6/IL-6RĪ±, thus preventing the formation of the IL-6/IL-6RĪ±/gp130 signalling complex. These findings shed light on the molecular mechanism of the anti-inflammatory action of LMWH and underpin its ability to influence favourably conditions characterised by overexpression of these two cytokines. Such conditions are not only associated with autoimmune diseases, but also with inflammatory processes, in particular with COVID-19. Our results put forward heparin as a promising means for the prevention and suppression of severe CRS and encourage further investigations on its applicability as an anti-inflammatory agent