A5050515086- Bacteriophages and microbial interactions
- RNA and protein synthesis mechanisms
- RNA modifications and cancer
- Genomics and Phylogenetic Studies
- Enzyme Structure and Function
- Peptidase Inhibition and Analysis
- Lipid Membrane Structure and Behavior
- Antibiotic Resistance in Bacteria
- Developmental Biology and Gene Regulation
- Genetic and Clinical Aspects of Sex Determination and Chromosomal Abnormalities
- Biochemical and Molecular Research
- Cancer therapeutics and mechanisms
- Viral gastroenteritis research and epidemiology
- Microbial bioremediation and biosurfactants
- Cellular transport and secretion
- Ion channel regulation and function
- Advanced Electron Microscopy Techniques and Applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- Colorectal Cancer Treatments and Studies
- Plant and Fungal Interactions Research
- Alzheimer's disease research and treatments
- Microbial Community Ecology and Physiology
- Plant Virus Research Studies
- Photosynthetic Processes and Mechanisms
- Pharmacological Effects of Natural Compounds
Institut de Biologie Intégrative de la Cellule
2018-2024
Université Paris-Saclay
2017-2024
Centre National de la Recherche Scientifique
2012-2024
CEA Paris-Saclay
2017-2024
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2017-2024
University of Colorado Boulder
2003-2024
Institut de Biologie Structurale
2022
Université Paris-Sud
2014-2018
Institut Pasteur
2006-2016
International Society for Optics and Photonics
2015
Synaptic vesicles are organelles with a precisely defined protein and lipid composition
A systematic survey for the presence of plasmids in 17 different xenobiotic-degrading Sphingomonas strains was performed. In almost all analyzed strains, two to five with sizes about 50 500 kb were detected by using pulsed-field gel electrophoresis. comparison plasmid preparations untreated or treated S1 nuclease suggested that, general, are circular. Hybridization experiments labeled gene probes that large involved degradation dibenzo-p-dioxin, dibenzofuran, and naphthalenesulfonates S....
N6-threonylcarbamoyladenosine (t6A) is a modified nucleotide found in all transfer RNAs (tRNAs) decoding codons starting with adenosine. Its role to facilitate codon–anticodon pairing and prevent frameshifting during protein synthesis. Genetic studies demonstrated that two universal proteins, Kae1/YgjD Sua5/YrdC, are necessary for t6A synthesis Saccharomyces cerevisiae Escherichia coli. In Archaea Eukarya, Kae1 part of conserved complex named kinase, endopeptidase other proteins small size...
N 6 -threonylcarbamoyladenosine (t A) is a universal tRNA modification essential for normal cell growth and accurate translation. In Archaea Eukarya, the protein Sua5 conserved KEOPS/EKC complex together catalyze t A biosynthesis. The composed of Kae1, metalloprotein belonging to ASHKA superfamily ATPases; Bud32, an atypical kinase two small proteins, Cgi121 Pcc1. this study, we investigated requirement functional role subunits biosynthesis A. We demonstrated that Pcc1, Kae1 Bud32 form...
Compromised protein homeostasis underlies accumulation of plaques and tangles in Alzheimer's disease (AD). To observe turnover at early stages amyloid beta (Aβ) proteotoxicity, we performed pulse-chase proteomics on mouse brains three genetic models AD that knock alleles precursor (APP) prior to the during progression. At initial Aβ accumulation, proteins associated with presynaptic terminals is selectively impaired. Presynaptic impaired turnover, particularly synaptic vesicle...
In Xenopus laevis, β-catenin-mediated dorsal axis formation can be suppressed by overexpression of the HMG-box transcription factor XSOX3. Mutational analysis indicates that this effect is due not to binding XSOX3 β-catenin nor its competition with β-catenin-regulated TCF-type factors for specific DNA sites, but rather SOX3 sites within promoter early VegT- andβ-catenin-regulated dorsal-mesoderm-inducing gene Xnr5. Although B1-type SOX proteins, such as XSOX3, are commonly thought act...
Abstract Early in vertebrate development, endodermal signals act on mesoderm to induce cardiogenesis. The F‐type SOXs SOX7 and SOX18β are expressed the cardiogenic region of early Xenopus embryo. Injection RNAs encoding or SOX18β, but not related SOX, SOX17, leads nodal‐dependent expression markers cardiogenesis animal cap explants. morpholinos directed against either SOX18mRNAs lead a partial inhibition vivo, while co‐injection SOX18 strongly inhibited RNA rescued effects morpholino visa...
The plasmids from 16 sphingomonads which degrade various xenobiotics and polycyclic aromatic compounds were compared with the previously sequenced plasmid pNL1 Sphingomonas aromaticivorans F199. replicase genes repAaAb amplified by PCR used as a gene probe for identification of belonging to same incompatibility group pNL1. Plasmids prepared hybridized repA probe. Positive hybridization signals obtained approximately 160-195 kb subterranea S. B0695, had been isolated subsurface location also...
The synaptotagmin (syt) proteins have been widely studied for their role in regulating fusion of intracellular vesicles with the plasma membrane. Here we report that syt-17, an unusual isoform unknown function, plays no exocytosis, and instead multiple roles membrane trafficking. Syt-17 is localized to Golgi complex hippocampal neurons, where it coordinates import from endoplasmic reticulum support neurite outgrowth facilitate axon regrowth after injury. Further, discovered a second pool...
ABSTRACT Four novel filamentous viruses with double-stranded DNA genomes, namely, Acidianus virus 3 (AFV3), AFV6, AFV7, and AFV8, have been characterized from the hyperthermophilic archaeal genus , they are assigned to Betalipothrixvirus of family Lipothrixviridae . The structures approximately 2-μm-long virions similar, one them, AFV3, was studied in detail. It consists a cylindrical envelope containing globular subunits arranged helical formation that is unique for any known virus. 3.1 nm...
Nature has established two mechanistically and structurally unrelated families of thymidylate synthases that produce de novo or dTMP, an essential DNA precursor. Representatives the alternative flavin-dependent synthase family, ThyX, are found in a large number microbial genomes, but absent humans. We have exploited nucleotide binding pocket ThyX proteins to identify non-substrate-based tight-binding inhibitors inhibited growth genetically modified Escherichia coli cells dependent on thyX...
Threonylcarbamoyladenosine (t(6)A) is a universal modification located in the anticodon stem-loop of tRNAs. In yeast, both cytoplasmic and mitochondrial tRNAs are modified. The t(6)A synthesis pathway was elucidated requires Sua5p, Kae1p, four other KEOPS complex proteins. Recent vitro work suggested that machinery Saccharomyces cerevisiae composed only two proteins, Sua5p Qri7p, member Kae1p/TsaD family (L. C. K. Wan et al., Nucleic Acids Res. 41:6332-6346, 2013,...
At present very little is known about interactions between extrachromosomal genetic elements in Archaea. Here we describe an Acidianus strain which carries naturally a novel 28 kb conjugative plasmid-like element, pAH1, and also serves as laboratory host for lipothrixvirus AFV1. In attempt to establish system studying plasmid-virus characterized the genome of pAH1 closely resembles those Sulfolobus plasmids pARN3 pARN4. integrates site specifically into, excises from, chromosome indicating...
Abstract DNA gyrase is a type II topoisomerase with the unique capacity to introduce negative supercoiling in DNA. In bacteria, has an essential role homeostatic regulation of supercoiling. While ubiquitous was previously reported have patchy distribution Archaea but its emergent function and evolutionary history this domain life remains elusive. study, we used phylogenomic approaches up-to date sequence dataset establish global archaea-specific phylogenies gyrases. The most parsimonious...
Abstract In Archaea and Eukaryotes, the synthesis of a universal tRNA modification, N 6 -threonyl-carbamoyl adenosine (t A), is catalyzed by KEOPS complex composed Kae1, Bud32, Cgi121, Pcc1. A fifth subunit, Gon7, found only in Fungi Metazoa. Here, we identify characterize subunit Archaea. This protein, dubbed Pcc2, paralog Pcc1 widely conserved Pcc2 form heterodimer solution, show modest sequence conservation but very high structural similarity. The five-subunit archaeal does not dimers...
Significance An alternate strategy to tubular or 2D crystals for high-resolution membrane protein structure determination by electron microscopy has been developed. Homogeneous polyhedral proteoliposomes of defined symmetry were prepared from the Escherichia coli mechanosensitive channel small conductance (MscS). These nanoparticles (MPPNs) analyzed cryomicroscopy that established they contain 24 MscS heptamers related octahedral wherein individual conformation resembles nonconducting state....
The exceptional genomic content and genome organization of the Acidianus filamentous virus 1 (AFV1) that infects hyperthermophilic archaeon hospitalis suggest this might exploit an unusual mechanism replication. An analysis replicative intermediates viral by two-dimensional (2D) agarose gel electrophoresis revealed replication starts formation a D-loop proceeds via strand displacement Characterization using dark-field electron microscopy, in combination with 2D data, suggests recombination...
TsaC/Sua5 family of enzymes catalyzes the first step in synthesis N6-threonyl-carbamoyl adenosine (t6A) one few truly ubiquitous tRNA modifications important for translation accuracy. TsaC is a single domain protein while Sua5 proteins contains TsaC-like and an additional SUA5 unknown function. The emergence these two their respective mechanisms t6A remain poorly understood. Here, we performed phylogenetic comparative sequence structure analysis proteins. We confirm that this but...