109 research outputs found
DAXX adds a de novo H3.3K9me3 deposition pathway to the histone chaperone network
A multitude of histone chaperones are required to support histones from their biosynthesis until DNA deposition. They cooperate through the formation of histone co-chaperone complexes, but the crosstalk between nucleosome assembly pathways remains enigmatic. Using exploratory interactomics, we define the interplay between human histone H3-H4 chaperones in the histone chaperone network. We identify previously uncharacterized histone-dependent complexes and predict the structure of the ASF1 and SPT2 co-chaperone complex, expanding the role of ASF1 in histone dynamics. We show that DAXX provides a unique functionality to the histone chaperone network, recruiting histone methyltransferases to promote H3K9me3 catalysis on new histone H3.3-H4 prior to deposition onto DNA. Hereby, DAXX provides a molecular mechanism for de novo H3K9me3 deposition and heterochromatin assembly. Collectively, our findings provide a framework for understanding how cells orchestrate histone supply and employ targeted deposition of modified histones to underpin specialized chromatin states
PARP14 and PARP9/DTX3L regulate interferon-induced ADP-ribosylation
PARP-catalysed ADP-ribosylation (ADPr) is important in regulating various cellular pathways. Until recently, PARP-dependent mono-ADP-ribosylation has been poorly understood due to the lack of sensitive detection methods. Here, we utilised an improved antibody to detect mono-ADP-ribosylation. We visualised endogenous interferon (IFN)-induced ADP-ribosylation and show that PARP14 is a major enzyme responsible for this modification. Fittingly, this signalling is reversed by the macrodomain from SARS-CoV-2 (Mac1), providing a possible mechanism by which Mac1 counteracts the activity of antiviral PARPs. Our data also elucidate a major role of PARP9 and its binding partner, the E3 ubiquitin ligase DTX3L, in regulating PARP14 activity through protein-protein interactions and by the hydrolytic activity of PARP9 macrodomain 1. Finally, we also present the first visualisation of ADPr-dependent ubiquitylation in the IFN response. These approaches should further advance our understanding of IFN-induced ADPr and ubiquitin signalling processes and could shed light on how different pathogens avoid such defence pathways
Bigraphical Refinement
We propose a mechanism for the vertical refinement of bigraphical reactive
systems, based upon a mechanism for limiting observations and utilising the
underlying categorical structure of bigraphs. We present a motivating example
to demonstrate that the proposed notion of refinement is sensible with respect
to the theory of bigraphical reactive systems; and we propose a sufficient
condition for guaranteeing the existence of a safety-preserving vertical
refinement. We postulate the existence of a complimentary notion of horizontal
refinement for bigraphical agents, and finally we discuss the connection of
this work to the general refinement of Reeves and Streader.Comment: In Proceedings Refine 2011, arXiv:1106.348
Potential role of endocrine gastrin in the colonic adenoma carcinoma sequence
The role of hyper-gastrinaemia in the incidence of colonic cancer remains to be clarified. The aim of this study was to determine whether cholecystokinin-2 (CCK-2) receptor expression predicts the sensitivity of human colonic adenomas to the proliferative effects of serum hyper-gastrinaemia. Gene expression of the classical (74 kDa) CCK-2 receptor in human colonic adenoma specimens and cell lines, was quantified by real-time PCR. Western blotting, using a CCK-2 receptor antiserum, confirmed protein expression. A transformed human colonic adenoma was grown in SCID mice, with hyper-gastrinaemia induced by protein pump inhibitors. CCK-2 receptor blockade was achieved by using neutralising antiserum. Both human colonic adenoma cell lines and biopsies expressed CCK-2 receptor mRNA at levels comparable with CCK-2 receptor transfected fibroblasts and oxyntic mucosa. Western blotting confirmed immunoreactive CCK-2 receptor bands localised to 45, 74 and 82.5 kDa. Omeprazole and lansoprazole-induced hyper-gastrinaemia (resulting in serum gastrin levels of 34.0 and 153.0 pM, respectively) significantly increased the weight of the human adenoma grafts (43% (P=0.016) and 70% (P=0.014), respectively). The effect of hypergastrinaemia on tumour growth was reversed by use of antiserum directed against the CCK-2 receptor. Hyper-gastrinaemia may promote proliferation of human colonic adenomas that express CCK-2 receptor isoforms
Setting a baseline for global urban virome surveillance in sewage
The rapid development of megacities, and their growing connectedness across the world is becoming a distinct driver for emerging disease outbreaks. Early detection of unusual disease emergence and spread should therefore include such cities as part of risk-based surveillance. A catch-all metagenomic sequencing approach of urban sewage could potentially provide an unbiased insight into the dynamics of viral pathogens circulating in a community irrespective of access to care, a potential which already has been proven for the surveillance of poliovirus. Here, we present a detailed characterization of sewage viromes from a snapshot of 81 high density urban areas across the globe, including in-depth assessment of potential biases, as a proof of concept for catch-all viral pathogen surveillance. We show the ability to detect a wide range of viruses and geographical and seasonal differences for specific viral groups. Our findings offer a cross-sectional baseline for further research in viral surveillance from urban sewage samples and place previous studies in a global perspective
Compatibility of physical education curricula with physical literacy across 40 European countries
Although the student-centred concept of physical literacy (PL) has been emphasized by UNESCO, knowledge about its adoption/implementation into PE remains scant. Therefore, the goal of this study was to evaluate and compare the compatibility of PE curricula with PL in Europe. We collaboratively gathered a panel of experts encompassing 40 European countries. In the first step, the experts were invited to freely specify the compatibility of country’s PE curricula with PL. The reports were subjected to six-step reflexive thematic analysis. In the second step, we theoretically derived, psychometrically explored, and descriptively analysed 15 curricular-didactical items, each containing a spectrum of statements with high versus no/insufficient PL compatibility. We synthesized both data sources following an explanatory sequential mixed-methods design. While few PE curricula explicitly adhered to PL in Europe, most documents exhibited content and aims marking elements of PL. However, we registered large differences in PL-compatibility between four European regions for the deep structure of the curricula (η2=.27, p=.01). While the quantitative survey suggested no differences in PL compatibility between anglophone versus non-anglophone countries, the qualitative material revealed conceptual and terminological challenges across Europe. The European countries have hesitantly followed the UNESCO call to align PE with the holistic PL concept
PARP14 is a PARP with both ADP-ribosyl transferase and hydrolase activities
This is the final version. Available on open access from the American Association for the Advancement of Science via the DOI in this recordData availability:
The MS proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE (92) partner repository with the dataset identifier PXD043452.PARP14 is a mono-ADP-ribosyl transferase involved in the control of immunity, transcription, and DNA replication stress management. However, little is known about the ADP-ribosylation activity of PARP14, including its substrate specificity or how PARP14-dependent ADP-ribosylation is reversed. We show that PARP14 is a dual-function enzyme with both ADP-ribosyl transferase and hydrolase activity acting on both protein and nucleic acid substrates. In particular, we show that the PARP14 macrodomain 1 is an active ADP-ribosyl hydrolase. We also demonstrate hydrolytic activity for the first macrodomain of PARP9. We reveal that expression of a PARP14 mutant with the inactivated macrodomain 1 results in a marked increase in mono(ADP-ribosyl)ation of proteins in human cells, including PARP14 itself and antiviral PARP13, and displays specific cellular phenotypes. Moreover, we demonstrate that the closely related hydrolytically active macrodomain of SARS2 Nsp3, Mac1, efficiently reverses PARP14 ADP-ribosylation in vitro and in cells, supporting the evolution of viral macrodomains to counteract PARP14-mediated antiviral response.Biotechnology and Biological Sciences Research Council (BBSRC)Wellcome TrustOxford University Challenge Seed FundEdward Penley Abraham Research FundOvarian Cancer Research AllianceResearch Council of NorwaySwedish Research CouncilMedical Research Council (MRC)Novo Nordisk Foundation Center for Protein ResearchDanish Council of Independent ResearchDanish Cancer Societ
Play, Learn, and Teach Outdoors—Network (PLaTO-Net): terminology, taxonomy, and ontology
Background: A recent dialogue in the field of play, learn, and teach outdoors (referred to as “PLaTO” hereafter) demonstrated the need for developing harmonized and consensus-based terminology, taxonomy, and ontology for PLaTO. This is important as the field evolves and diversifies in its approaches, contents, and contexts over time and in different countries, cultures, and settings. Within this paper, we report the systematic and iterative processes undertaken to achieve this objective, which has built on the creation of the global PLaTO-Network (PLaTO-Net). Methods: This project comprised of four major methodological phases. First, a systematic scoping review was conducted to identify common terms and definitions used pertaining to PLaTO. Second, based on the results of the scoping review, a draft set of key terms, taxonomy, and ontology were developed, and shared with PLaTO members, who provided feedback via four rounds of consultation. Third, PLaTO terminology, taxonomy, and ontology were then finalized based on the feedback received from 50 international PLaTO member participants who responded to ≥ 3 rounds of the consultation survey and dialogue. Finally, efforts to share and disseminate project outcomes were made through different online platforms. Results: This paper presents the final definitions and taxonomy of 31 PLaTO terms along with the PLaTO-Net ontology model. The model incorporates other relevant concepts in recognition that all the aspects of the model are interrelated and interconnected. The final terminology, taxonomy, and ontology are intended to be applicable to, and relevant for, all people encompassing various identities (e.g., age, gender, culture, ethnicity, ability). Conclusions: This project contributes to advancing PLaTO-based research and facilitating intersectoral and interdisciplinary collaboration, with the long-term goal of fostering and strengthening PLaTO’s synergistic linkages with healthy living, environmental stewardship, climate action, and planetary health agendas. Notably, PLaTO terminology, taxonomy and ontology will continue to evolve, and PLaTO-Net is committed to advancing and periodically updating harmonized knowledge and understanding in the vast and interrelated areas of PLaTO
Compatibility of physical education curricula with physical literacy across 40 European countries
Although the student-centred concept of physical literacy (PL) has been emphasized by UNESCO, knowledge about its adoption/implementation into PE remains scant. Therefore, the goal of this study was to evaluate and compare the compatibility of PE curricula with PL in Europe. We collaboratively gathered a panel of experts encompassing 40 European countries. In the first step, the experts were invited to freely specify the compatibility of country’s PE curricula with PL. The reports were subjected to six-step reflexive thematic analysis. In the second step, we theoretically derived, psychometrically explored, and descriptively analysed 15 curricular-didactical items, each containing a spectrum of statements with high versus no/insufficient PL compatibility. We synthesized both data sources following an explanatory sequential mixed-methods design. While few PE curricula explicitly adhered to PL in Europe, most documents exhibited content and aims marking elements of PL. However, we registered large differences in PL-compatibility between four European regions for the deep structure of the curricula (η2=.27, p=.01). While the quantitative survey suggested no differences in PL compatibility between anglophone versus non-anglophone countries, the qualitative material revealed conceptual and terminological challenges across Europe. The European countries have hesitantly followed the UNESCO call to align PE with the holistic PL concept
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