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Differential redox sensitivity of tRNA dihydrouridylation
No full textInternational audienceAbstract Various transfer RNA (tRNA) modifications have recently been shown to regulate stress-dependent gene expression by modulating messenger RNA translation. Among these modifications, dihydrouridine stands out for its increase of tRNA structural flexibility. However, whether and how dihydrouridine synthesis reacts to environmental stimuli is largely unknown. In this study, we manipulated the intracellular redox state of Escherichia coli using paraquat, revealing differential sensitivities of the three tRNA-dihydrouridine synthases towards oxidative stress. Using liquid chromatography–mass spectrometry quantification of dihydrouridine in various knockout strains, we validated the use of a specific RNA sequencing method, namely AlkAnilineSeq, for the precise mapping of dihydrouridines throughout E. coli tRNAs. We found DusA showing high activity, followed by DusB and DusC, whose activity was decreased under paraquat treatment. The relative sensitivity is most plausibly explained by a paraquat-dependent drop of NADPH availability. These findings are substantiated by in vitro kinetics, revealing DusA as the most active enzyme, followed by DusB, while DusC showed little activity, likely related to the efficacy of the redox reaction of the flavin coenzyme with NADPH. Overall, our study underscores the intricate interplay between redox dynamics and tRNA modification processes, revealing a new facet of the regulatory mechanisms influencing cellular responses to oxidative stress
Static and Dynamic Verification of OCaml Programs: The Gospel Ecosystem
No full textInternational audienceWe present our work on the collaborative use of dynamic and static analysis tools for the verification of software written in the OCaml language. We build upon Gospel, a specification language for OCaml that can be used both in dynamic and static analyses. We employ Ortac, forruntime assertion checking, and Cameleer and CFML for the deductive verification of OCaml code. We report on the use of such tools to build a case study of collaborative analysis of a non-trivial OCaml program. This shows how these tools nicely complement each others, while at the samehighlights the differences when writing specification targeting dynamic or static analysis methods
L’orientalisme en train de se faire: Une enquête collective sur les études orientales dans l’Algérie coloniale
No full textInternational audienc
Pratiques et savoirs géographiques chinois, IIIe-Xe siècles. Le Livre des barbares (Manshu) de Fan Chuo (suite)
No full textInternational audienceProgramme de l’année 2022-2023 : Le Livre des barbares (Manshu) de Fan Chuo (suite)
La Quintessence Immaculée clarifiant le Commentaire du Tantra de la Perfection Intégrale du Fruit (‘Bras bu yongs rdzogs rgyud kyi ti ka gsal byed dri med snying po)
No full textLes Cinq Sceaux des Points-Clefs des Précieux Préliminaires (sNgon ‘gro rin po che gnad kyi gzer lnga)
No full textCNCA aligns small annotated genomes
No full textInternational audienceBackground: To explore the evolutionary history of sequences, a sequence alignment is a first and necessary step, and its quality is crucial. In the context of the study of the proximal origins of SARS-CoV-2 coronavirus, we wanted to construct an alignment of genomes closely related to SARS-CoV-2 using both coding and non-coding sequences. To our knowledge, there is no tool that can be used to construct this type of alignment, which motivated the creation of CNCA.Results: CNCA is a web tool that aligns annotated genomes from GenBank files. It generates a nucleotide alignment that is then updated based on the protein sequence alignment. The output final nucleotide alignment matches the protein alignment and guarantees no frameshift. CNCA was designed to align closely related small genome sequences up to 50 kb (typically viruses) for which the gene order is conserved.Conclusions: CNCA constructs multiple alignments of small genomes by integrating both coding and non-coding sequences. This preserves regions traditionally ignored in conventional back-translation methods, such as non-coding regions
保岡勝也の建築思想における茶室と数寄屋の位置について
No full textInternational audienceThis paper analyses the place of the tea house in the thought the architect Yasuoka Katsuya, Japan’s first housing theoretician.After a presentation of the architect’s theory, the article focuses on the following points:1. Yasuoka’s concept of the tea house and the originality of his thought.2. The opposite value of sukiya and tea house in Yasuoka’s theory.3. The tea house in Yasuoka’s housing theory and architectural practice
