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131.
Guillaume Fouché Thomas Michel Anaïs Lalève Nick X. Wang David H. Young Brigitte Meunier Danièle Debieu Sabine Fillinger Anne-Sophie Walker 《Environmental microbiology》2022,24(3):1117-1132
Acquired resistance is a threat to antifungal efficacy in medicine and agriculture. The diversity of possible resistance mechanisms and highly adaptive traits of pathogens make it difficult to predict evolutionary outcomes of treatments. We used directed evolution as an approach to assess the resistance risk to the new fungicide fenpicoxamid in the wheat pathogenic fungus Zymoseptoria tritici. Fenpicoxamid inhibits complex III of the respiratory chain at the ubiquinone reduction site (Qi site) of the mitochondrially encoded cytochrome b, a different site than the widely used strobilurins which inhibit the same complex at the ubiquinol oxidation site (Qo site). We identified the G37V change within the cytochrome b Qi site as the most likely resistance mechanism to be selected in Z. tritici. This change triggered high fenpicoxamid resistance and halved the enzymatic activity of cytochrome b, despite no significant penalty for in vitro growth. We identified negative cross-resistance between isolates harbouring G37V or G143A, a Qo site change previously selected by strobilurins. Double mutants were less resistant to both QiIs and quinone outside inhibitors compared to single mutants. This work is a proof of concept that experimental evolution can be used to predict adaptation to fungicides and provides new perspectives for the management of QiIs. 相似文献
132.
Kim M. Keppler-Noreuil Julie C. Sapp Marjorie J. Lindhurst Thomas N. Darling Jasmine Burton-Akright Mohammadhadi Bagheri Eva Dombi Ashlyn Gruber Paul F. Jarosinski Staci Martin Neera Nathan Scott M. Paul Ronald E. Savage Pamela L. Wolters Brian Schwartz Brigitte C. Widemann Leslie G. Biesecker 《American journal of human genetics》2019,104(3):484-491
133.
134.
Pertschy B Zisser G Schein H Köffel R Rauch G Grillitsch K Morgenstern C Durchschlag M Högenauer G Bergler H 《Molecular and cellular biology》2004,24(14):6476-6487
Diazaborine treatment of yeast cells was shown previously to cause accumulation of aberrant, 3'-elongated mRNAs. Here we demonstrate that the drug inhibits maturation of rRNAs for the large ribosomal subunit. Pulse-chase analyses showed that the processing of the 27S pre-rRNA to consecutive species was blocked in the drug-treated wild-type strain. The steady-state level of the 7S pre-rRNA was clearly reduced after short-term treatment with the inhibitor. At the same time an increase of the 35S pre-rRNA was observed. Longer incubation with the inhibitor resulted in a decrease of the 27S precursor. Primer extension assays showed that an early step in 27S pre-rRNA processing is inhibited, which results in an accumulation of the 27SA2 pre-rRNA and a strong decrease of the 27SA3, 27SB1L, and 27SB1S precursors. The rRNA processing pattern observed after diazaborine treatment resembles that reported after depletion of the RNA binding protein Nop4p/Nop77p. This protein is essential for correct pre-27S rRNA processing. Using a green fluorescent protein-Nop4 fusion, we found that diazaborine treatment causes, within minutes, a rapid redistribution of the protein from the nucleolus to the periphery of the nucleus, which provides a possible explanation for the effect of diazaborine on rRNA processing. 相似文献
135.
Cnidarians represent the first animal phylum with an organized nervous system and a complex active behavior. The hydra nervous system is formed of sensory-motoneurons, ganglia neurons and mechanoreceptor cells named nematocytes, which all differentiate from a common stem cell. The neurons are organized as a nerve net and a subset of neurons participate in a more complex structure, the nerve ring that was identified in most cnidarian species at the base of the tentacles. In order to better understand the genetic control of this neuronal network, we analysed the expression of evolutionarily conserved regulatory genes in the hydra nervous system. The Prd-class homeogene prdl-b and the nuclear orphan receptor hyCOUP-TF are expressed at strong levels in proliferating nematoblasts, a lineage where they were found repressed during patterning and morphogenesis, and at low levels in distinct subsets of neurons. Interestingly, Prd-class homeobox and COUP-TF genes are also expressed during neurogenesis in bilaterians, suggesting that mechanoreceptor and neuronal cells derive from a common ancestral cell. Moreover, the Prd-class homeobox gene prdl-a, the Antp-class homeobox gene msh, and the thrombospondin-related gene TSP1, which are expressed in distinct subset of neurons in the adult polyp, are also expressed during early budding and/or head regeneration. These data strengthen the fact that two distinct regulations, one for neurogenesis and another for patterning, already apply to these regulatory genes, a feature also identified in bilaterian related genes. 相似文献
136.
RNA localization in subcytoplasmic areas is a process known for more than twenty years, and more than a hundred RNAs have now been shown to be spatially regulated. In most cases, RNA localization is involved in cell polarity, either by reading spatial clues and translating them into a spatial regulation of gene expression, or more directly by controlling cytoskeletal polarity. In this review, the various functions of RNA localization will be presented, and by analyzing two examples, Ash1 mRNA in yeast and retroviral genomic RNAs in mammals, the reader will be taken step by step into the detailed mechanisms of this fascinating process. 相似文献
137.
In many species, intracellular mRNA localization is linked to cell polarity. In many cases however, mRNAs become localized as a result of a pre-existing cell-polarity, and they do not modify it. Remarkably, in the case beta actin mRNA in vertebrate, it has been shown that the transport and localization of this RNA is required for the establishment and maintenance of cell polarity. This occurs in fibroblasts, but, very interestingly, in immature neurons as well. This review will describe the functions and mechanisms of actin mRNA localization. 相似文献
138.
Géraldine?Verquin Ga?lle?Fontaine Marc?Bria Elena?Zhilinskaya Edmond?Abi-Aad Antoine?Abouka?s Brigitte?Baldeyrou Christian?Bailly Jean-Luc?BernierEmail author 《Journal of biological inorganic chemistry》2004,9(3):345-353
Oxovanadium(IV) complexes of hydroxysalen derivatives have been prepared and tested as DNA reactive agents. The nuclease activity has been investigated under oxidative or reducing conditions, on the basis of the various oxidation states of vanadium: VIII, VIV and VV. In the absence of an activating agent, none of the compounds tested was able to induce cleavage of DNA, whereas in the presence of mercaptopropionic acid (MPA) or Oxone the four complexes induced DNA modifications. Under both conditions, the para-hydroxy complex was found to be the most active compound. Reaction of these salen complexes with DNA occurs essentially at guanine residues and is more efficient in the presence of Oxone than under reducing conditions. The extent of Oxone-mediated DNA oxidation by the four vanadyl complexes was clearly superior to VOSO4
and was observed without piperidine treatment. EPR studies provided information on the reactive metal-oxo species involved under each conditions and a mechanism of reaction with DNA is discussed.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00775-004-0529-0Abbreviations BPE buffer
bis-phosphate EDTA buffer
- DMPO
5,5-dimethylpyrroline
N-oxide
- DMS
dimethyl sulfate
- HFS
hyperfine structure
- Lin
linear
- MPA
3-mercaptopropionic acid
- Nck
nicked
- salen
(salicylidene)ethylenediamine
- Sc
supercoiled
- TBE buffer
tris-borate EDTA buffer
- Tris
tris(hydroxymethyl)aminomethane 相似文献
139.
140.
A divergent ADP/ATP carrier in the hydrogenosomes of Trichomonas gallinae argues for an independent origin of these organelles 总被引:2,自引:0,他引:2
Tjaden J Haferkamp I Boxma B Tielens AG Huynen M Hackstein JH 《Molecular microbiology》2004,51(5):1439-1446
The evolution of mitochondrial ADP and ATP exchanging proteins (AACs) highlights a key event in the evolution of the eukaryotic cell, as ATP exporting carriers were indispensable in establishing the role of mitochondria as ATP-generating cellular organelles. Hydrogenosomes, i.e. ATP- and hydrogen-generating organelles of certain anaerobic unicellular eukaryotes, are believed to have evolved from the same ancestral endosymbiont that gave rise to present day mitochondria. Notably, the hydrogenosomes of the parasitic anaerobic flagellate Trichomonas seemed to be deficient in mitochondrial-type AACs. Instead, HMP 31, a different member of the mitochondrial carrier family (MCF) with a hitherto unknown function, is abundant in the hydrogenosomal membranes of Trichomonas vaginalis. Here we show that the homologous HMP 31 of closely related Trichomonas gallinae specifically transports ADP and ATP with high efficiency, as do genuine mitochondrial AACs. However, phylogenetic analysis and its resistance against bongkrekic acid (BKA, an efficient inhibitor of mitochondrial-type AACs) identify HMP 31 as a member of the mitochondrial carrier family that is distinct from all mitochondrial and hydrogenosomal AACs studied so far. Thus, our data support the hypothesis that the various hydrogenosomes evolved repeatedly and independently. 相似文献