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South Asian Nationalisms: Concluding Reflections

In this concluding commentary, the overall theme of the special issue as well as the collective contribution of the individual articles are addressed and elaborated upon. In particular, it focuses on the manifold commonalities that exist between South Asian states—both in terms of shared traits or dynamics and the recurrent attribution of negative connotations to neighboring states—and how these i

International Forum on Policies and Practice for Transfusion of ABO and RhD Non-Identical Platelets : Summary

Transfusion of ABO major incompatible platelets (where the recipient has antibodies against the ABO group of the transfused platelets) has been shown to be associated with lower platelet count increments following transfusion [1], although this does not appear to translate to a difference in bleeding outcomes [2]. Transfusion of minor ABO incompatible platelets (where the suspending plasma of the

Slutrapportering av samordning av universitetets hantering av forskningsdata

Detta är slutrapportering av rektorsuppdraget Samordning av universitetets hantering av forskningsdata, Dnr STYR 2019/295. Rapporten beskriver forskningsdataområdets disruptiva natur och dess relation till e-infrastrukturområdet, hur ett samordningsuppdrag formaliserades och med tiden formerades, vilka underprojekt som initierats och delområden som bevakats, föreslår en färdplan inför nästa steg i

Rapport för projekt Verksamhetskartläggning forskningsdata : Ett underprojekt till uppdrag Samordning av universitetets hantering av forskningsdata

Projektet har gjort en kartläggning över Lunds universitets förmågor att stötta god forskningsdatahantering med hjälp av verksamhetsarkitekturella metoder. Kartläggningen grundar sig på intervjuermed forskare, workshops med forskare, intervjuer med expertroller och stödorganisationspersonal,samt enkät till stödorganisationer. Analyser av insamlat material har resulterat i grafiska representationer

The new geographies of popular music (in a pandemic) : Guilty geographies and compressed intimacies

In this paper, I analyse developments in the relationship between popular musicians and their audiences that have intensified during the COVID-19 pandemic of 2020–21. The first, guilty geographies, concerns musicians and music venues becoming increasingly reliant on charitable audience support, appealing to fans’ ethical consciences through the crowdfunding (or fan-funding) model. The second, comp

Sex differences in off-target binding using tau positron emission tomography

Purpose: Off-target binding in the skull and meninges is observed in some subjects undergoing tau positron emission tomography (PET) and could potentially differ between men and women. In this study we elucidate sex differences in tau off-target binding using three different tau PET tracers. Methods: 541 cognitively unimpaired amyloid-β negative participants underwent tau PET using [18F]flortaucip

The RelA/SpoT Homolog (RSH) superfamily : Distribution and functional evolution of ppgpp synthetases and hydrolases across the tree of life

RelA/SpoT Homologue (RSH) proteins, named for their sequence similarity to the RelA and SpoT enzymes of Escherichia coli, comprise a superfamily of enzymes that synthesize and/or hydrolyze the alarmone ppGpp, activator of the "stringent" response and regulator of cellular metabolism. The classical "long" RSHs Rel, RelA and SpoT with the ppGpp hydrolase, synthetase, TGS and ACT domain architecture

Structure of the Dom34-Hbs1 complex and implications for no-go decay

No-go decay (NGD) targets mRNAs with stalls in translation elongation for endonucleolytic cleavage in a process involving the Dom34 and Hbs1 proteins. The crystal structure of a Schizosaccharomyces pombe Dom34-Hbs1 complex reveals an overall shape similar to that of eRF1-eRF3-GTP and EF-Tu-tRNA-GDPNP. Similarly to eRF1 and GTP binding to eRF3, Dom34 and GTP bind to Hbs1 with strong cooperativity,

Mechanism of tetracycline resistance by ribosomal protection protein Tet(O)

Tetracycline resistance protein Tet(O), which protects the bacterial ribosome from binding the antibiotic tetracycline, is a translational GTPase with significant similarity in both sequence and structure to the elongation factor EF-G. Here, we present an atomic model of the Tet(O)-bound 70S ribosome based on our cryo-electron microscopic reconstruction at 9.6-Å resolution. This atomic model allow

GTPases IF2 and EF-G bind GDP and the SRL RNA in a mutually exclusive manner

Translational GTPases (trGTPases) are involved in all four stages of protein biosynthesis: initiation, elongation, termination and ribosome recycling. The trGTPases Initiation Factor 2 (IF2) and Elongation Factor G (EF-G) respectively orchestrate initiation complex formation and translocation of the peptidyl-tRNA:mRNA complex through the bacterial ribosome. The ribosome regulates the GTPase cycle

Thermodynamic Characterization of ppGpp Binding to EF-G or IF2 and of Initiator tRNA Binding to Free IF2 in the Presence of GDP, GTP, or ppGpp

In addition to their natural substrates GDP and GTP, the bacterial translational GTPases initiation factor (IF) 2 and elongation factor G (EF-G) interact with the alarmone molecule guanosine tetraphosphate (ppGpp), which leads to GTPase inhibition. We have used isothermal titration calorimetry to determine the affinities of ppGpp for IF2 and EF-G at a temperature interval of 5-25 °C. We find that

GTP-dependent structural rearrangement of the eRF1:eRF3 complex and eRF3 sequence motifs essential for PABP binding

Translation termination in eukaryotes is governed by the concerted action of eRF1 and eRF3 factors. eRF1 recognizes the stop codon in the A site of the ribosome and promotes nascent peptide chain release, and the GTPase eRF3 facilitates this peptide release via its interaction with eRF1. In addition to its role in termination, eRF3 is involved in normal and nonsense-mediated mRNA decay through its

An ancient family of SelB elongation factor-like proteins with a broad but disjunct distribution across archaea

Background: SelB is the dedicated elongation factor for delivery of selenocysteinyl-tRNA to the ribosome. In archaea, only a subset of methanogens utilizes selenocysteine and encodes archaeal SelB (aSelB). A SelB-like (aSelBL) homolog has previously been identified in an archaeon that does not encode selenosysteine, and has been proposed to be a pyrrolysyl-tRNA-specific elongation factor (EF-Pyl).

Evolution of nonstop, no-go and nonsense-mediated mRNA decay and their termination factor-derived components

Background. Members of the eukaryote/archaea specific eRF1 and eRF3 protein families have central roles in translation termination. They are also central to various mRNA surveillance mechanisms, together with the eRF1 paralogue Dom34p and the eRF3 paralogues Hbs1p and Ski7p. We have examined the evolution of eRF1 and eRF3 families using sequence similarity searching, multiple sequence alignment an

Thermodynamics of GTP and GDP Binding to Bacterial Initiation Factor 2 Suggests Two Types of Structural Transitions

During initiation of messenger RNA translation in bacteria, the GTPase initiation factor (IF) 2 plays major roles in the assembly of the preinitiation 30S complex and its docking to the 50S ribosomal subunit leading to the 70S initiation complex, ready to form the first peptide bond in a nascent protein. Rapid and accurate initiation of bacterial protein synthesis is driven by conformational chang

The pretranslocation ribosome is targeted by GTP-bound EF-G in partially activated form

Translocation of the tRNA·mRNA complex through the bacterial ribosome is driven by the multidomain guanosine triphosphatase elongation factor G (EF-G). We have used isothermal titration calorimetry to characterize the binding of GDP and GTP to free EF-G at 4°C, 20°C, and 37°C. The binding affinity of EF-G is higher to GDP than to GTP at 4°C, but lower at 37°C. The binding enthalpy and entropy chan

Positive allosteric feedback regulation of the stringent response enzyme RelA by its product

During the stringent response, Escherichia coli enzyme RelA produces the ppGpp alarmone, which in turn regulates transcription, translation and replication. We show that ppGpp dramatically increases the turnover rate of its own ribosome-dependent synthesis by RelA, resulting in direct positive regulation of an enzyme by its product. Positive allosteric regulation therefore constitutes a new mechan

The bacterial toxin RelE induces specific mRNA cleavage in the A site of the eukaryote ribosome

RelE/RelB is a well-characterized toxin-anti-toxin pair involved in nutritional stress responses in Bacteria and Archae. RelE lacks any eukaryote homolog, but we demonstrate here that it efficiently and specifically cleaves mRNA in the A site of the eukaryote ribosome. The cleavage mechanism is similar to that in bacteria, showing the feasibility of A-site cleavage of mRNA for regulatory purposes