Publications by authors named "Clave C"

Filamentous fungi display allorecognition genes that trigger regulated cell death (RCD) when strains of unlike genotype fuse. Podospora anserina is one of several model species for the study of this allorecognition process termed heterokaryon or vegetative incompatibility. Incompatibility restricts transmission of mycoviruses between isolates.

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Objective: The objective of our research was to investigate the heat-protecting effect of a product ex vivo and in vivo on human hair fibres.

Methods: A preparatory study was carried out in order to determine an optimal threshold of thermal stress. For this, the structure of cross-sections of the hair fibre was observed by optical microscopy.

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Allorecognition, the capacity to discriminate self from conspecific non-self, is a ubiquitous organismal feature typically governed by genes evolving under balancing selection. Here, we show that in the fungus Podospora anserina, allorecognition loci controlling vegetative incompatibility (het genes), define two reproductively isolated groups through pleiotropic effects on sexual compatibility. These two groups emerge from the antagonistic interactions of the unlinked loci het-r (encoding a NOD-like receptor) and het-v (encoding a methyltransferase and an MLKL/HeLo domain protein).

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Gasdermins are a family of pore-forming proteins controlling an inflammatory cell death reaction in the mammalian immune system. The pore-forming ability of the gasdermin proteins is released by proteolytic cleavage with the removal of their inhibitory C-terminal domain. Recently, gasdermin-like proteins have been discovered in fungi and characterized as cell death-inducing toxins in the context of conspecific non-self-discrimination (allorecognition).

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Meiotic drive is the preferential transmission of a particular allele during sexual reproduction. The phenomenon is observed as spore killing in multiple fungi. In natural populations of , seven spore killer types (s) have been identified through classical genetic analyses.

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In plants and metazoans, intracellular receptors that belong to the NOD-like receptor (NLR) family are major contributors to innate immunity. Filamentous fungal genomes contain large repertoires of genes encoding for proteins with similar architecture to plant and animal NLRs with mostly unknown function. Here, we identify and molecularly characterize patatin-like phospholipase-1 (PLP-1), an NLR-like protein containing an N-terminal patatin-like phospholipase domain, a nucleotide-binding domain (NBD), and a C-terminal tetratricopeptide repeat (TPR) domain.

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The [Het-s] prion of the fungus Podospora anserina represents a good model system for studying the structure-function relationship in amyloid proteins because a high resolution solid-state NMR structure of the amyloid prion form of the HET-s prion forming domain (PFD) is available. The HET-s PFD adopts a specific β-solenoid fold with two rungs of β-strands delimiting a triangular hydrophobic core. A C-terminal loop folds back onto the rigid core region and forms a more dynamic semi-hydrophobic pocket extending the hydrophobic core.

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In fungi, heterokaryon incompatibility is a nonself recognition process occurring when filaments of different isolates of the same species fuse. Compatibility is controlled by so-called het loci and fusion of strains of unlike het genotype triggers a complex incompatibility reaction that leads to the death of the fusion cell. Herein, we analyze the transcriptional changes during the incompatibility reaction in Podospora anserina.

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HET-s is a prion protein of the filamentous fungus Podospora anserina. An orthologue of this protein, called FgHET-s has been identified in Fusarium graminearum. The region of the FgHET-s protein corresponding to the prion forming domain of HET-s, forms amyloid fibrils in vitro.

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Background: The development of new microarray technologies makes custom long oligonucleotide arrays affordable for many experimental applications, notably gene expression analyses. Reliable results depend on probe design quality and selection. Probe design strategy should cope with the limited accuracy of de novo gene prediction programs, and annotation up-dating.

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Background: Genes involved in non-self recognition and host defence are typically capable of rapid diversification and exploit specialized genetic mechanism to that end. Fungi display a non-self recognition phenomenon termed heterokaryon incompatibility that operates when cells of unlike genotype fuse and leads to the cell death of the fusion cell. In the fungus Podospora anserina, three genes controlling this allorecognition process het-d, het-e and het-r are paralogs belonging to the same hnwd gene family.

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Sandhoff disease is an autosomal recessive lysosomal disorder due to mutations in the beta-hexosaminidase beta-chain gene, resulting in beta-hexosaminidases A (alphabeta) and B (betabeta) deficiency and GM2 ganglioside accumulation in the brain. In this study, our aim was to demonstrate that transduction of cerebral endothelial cells cultured in two-chamber culture inserts with a lentiviral vector encoding the hexosaminidases alpha and beta chains could induce a vectorial secretion of hexosaminidases. Therefore, the human cerebral endothelial cell line hCMEC/D3 was infected with the bicistronic vector from the apical compartment, and beta-hexosaminidase activity was measured in transduced cells and in deficient fibroblasts co-cultured in the basal (i.

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Autophagy has been monitored in the filamentous fungus Podospora anserina using electron, light, and fluorescence microscopy. In this organism autophagy can be induced either by starvation or rapamycin treatment or by het gene incompatibility. Incompatible HET products signal a cell death reaction referred to as cell death by incompatibility.

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In fungi, vegetative incompatibility is a conspecific non-self recognition mechanism that restricts formation of viable heterokaryons when incompatible alleles of specific het loci interact. In Podospora anserina, three non-allelic incompatibility systems have been genetically defined involving interactions between het-c and het-d, het-c and het-e, het-r and het-v. het-d and het-e are paralogues belonging to the HNWD gene family that encode proteins of the STAND class.

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Research in autophagy continues to accelerate,(1) and as a result many new scientists are entering the field. Accordingly, it is important to establish a standard set of criteria for monitoring macroautophagy in different organisms. Recent reviews have described the range of assays that have been used for this purpose.

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Vegetative incompatibility is a programmed cell death reaction that occurs when fungal cells of unlike genotypes fuse. Genes defining vegetative incompatibility (het genes) are highly polymorphic, and most if not all incompatibility systems include a protein partner bearing the fungus-specific domain termed the HET domain. The nonallelic het-C/het-E incompatibility system is the best-characterized incompatibility system in Podospora anserina.

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Conspecific allorecognition, the ability for an organism to discriminate its own cells from those of another individual of the same species, has been developed by many organisms. Allorecognition specificities are determined by highly polymorphic genes. The processes by which this extreme polymorphism is generated remain largely unknown.

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Filamentous fungi are naturally able of somatic fusions. When cells of unlike genotype at specific het loci fuse, non-self recognition operates in the fusion cell and a cell death reaction termed cell death by incompatibility is triggered. In Podospora anserina cell death by incompatibility is characterized by a dramatic vacuolar enlargement, induction of autophagy and cell lysis.

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We have isolated the Podospora anserina TOR gene. The PaTOR protein displayed strong identities with TOR proteins from other eukaryotes especially in the FRB domain and the kinase domain. Genome analysis suggests that a single TOR gene exists in Podospora.

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Although autophagy is characteristic of type II programmed cell death (PCD), its role in cell death is currently debated. Both cell death-promoting and prosurvival roles of autophagy have been reported depending on the organism and the cell type. In filamentous fungi, a cell death reaction known as an incompatibility reaction occurs when cells of unlike genotype fuse.

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In filamentous fungi a cell death reaction occurs when hyphae of unlike genotype fuse. This phenomenon is referred to as heterokaryon incompatibility. In Podospora anserina, this cell death reaction was found to be associated with the transcriptional induction of a set of genes termed idi genes (for induced during incompatibility) and activation of autophagy.

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In filamentous fungi, a programmed cell death (PCD) reaction occurs when cells of unlike genotype fuse. This reaction is caused by genetic differences at specific loci termed het loci (for heterokaryon incompatibility). Although several het genes have been characterized, the mechanism of this cell death reaction and its relation to PCD in higher eukaryotes remains largely unknown.

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In filamentous fungi, a cell death reaction occurs when cells of unlike genotype fuse. This cell death reaction, known as incompatibility reaction, is genetically controlled by a set of loci termed het loci (for heterokaryon incompatibility loci). In Podospora anserina, genes induced during this cell death reaction (idi genes) have been identified.

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In the filamentous fungi, cell fusion between unlike individuals generally triggers a cell-death reaction known as vegetative incompatibility. In Podospora anserina, it was shown that, during this cell-death reaction, there is a strong increase in proteolytic activity. Here, we report the purification of a 36-kDa protease that is induced during the incompatibility reaction.

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In filamentous fungi, vegetative cell fusion between genotypically distinct individuals leads to a cell-death reaction known as vegetative or heterokaryon incompatibility. Genes involved in this reaction have been characterised molecularly. We can now begin to get a better understanding of the mechanism and the biological significance of this intriguing phenomenon.

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