Project description:Data for the manuscript: Genomic and metabolomic analysis of the endophytic fungus Fusarium sp. VM-40 derived from the medicinal plant Vinca minor, authors: Ting He, Xiao Li, Riccardo Iacovelli, Thomas Hackl and Kristina Haslinger
Project description:Arteriovenous hemodialysis graft (AVG) stenosis results in thrombosis and AVG failure, and develops chiefly as a consequence of neotinimal hyperplasia (NH) formation in the graft-venous anastomosis region. Of note, the juxta-anastomotic vein regions are relatively resistant to NH. AVG stenosis has not been resolved partly due to our limited understanding of the molecular processes involved in the pathophysiology. We hypothesized that the gene expression profiles of the NH prone and NH-resistant regions will be different after graft placement, and analysis of their genomic profiles may yield therapeutic targets to address AVG stenosis. To test this hypothesis we evaluated the global genomic profiles of the graft-venous anastomosis (NH-prone) and juxta-anastomotic (NH-resistant) vein regions in a porcine model of AVG stenosis using a porcine microarray. Gene expression changes in these two distinct vein regions, relative to the gene expression in un-operated veins, were examined at an early (5 days) and later (14 days) time period following graft placement. Global genomic changes were much greater in the NH-prone region than in the NH-resistant region at both time points. In the NH-prone region, genes related to regulation of cell proliferation and osteo/chondrogenic vascular remodeling were most enriched among the significantly up-regulated genes at day 5 and day 14, respectively. At both time points, genes related to muscle phenotype were significantly down-regulated. These results provide insights into the spatial and temporal genomic modulation underlying NH formation in AVG, and suggest potential therapeutic strategies to prevent and/or limit AVG stenosis.
Project description:In mouse early pachytene spermatocytes, the X and Y chromosomes undergo rapid non-homologous (NH) synapsis and desynapsis, but the functional significance remains unknown. Here, we report that pachynema-specific knockout of Speedy A (SpdyA) from telomeres caused persistent Y-X NH synapsis, with the entire Y axis synapsed onto the X axis. This persistent Y-X NH synapsis did not interrupt meiotic sex chromosome inactivation, recombination, or sex body formation, but it disrupted X-Y loop-axis organization and homologous X-Y desynapsis, leading to spermatocyte death. Similarly, persistent Y-X NH synapsis was also observed in pachytene spermatocytes lacking TRF1, where SpdyA was frequently lost from X-Y non-pseudoautosomal region (non-PAR) telomeres. Mechanistic studies revealed that the Serine 48 of SUN1 is a key SpdyA/CDK2 phosphorylation site needed for Y-X NH desynapsis. We propose that SpdyA governs Y-X NH desynapsis by stabilizing the linkage between the X-Y non-PAR telomeres and their LINC complexes, and that this process is regulated independently from other aspects of pachynema progression. Our findings suggest a key role for Y-X NH desynapsis in establishing proper X-Y loop-axis organization.
Project description:The genomes of many filamentous fungi consist of a 'core' part containing conserved genes essential for normal development as well as conditionally dispensable (CD) or lineage-specific (LS) chromosomes. In the plant-pathogenic fungus Fusarium oxysporum f. sp. lycopersici, one LS chromosome harbours effector genes that contribute to pathogenicity. We employed flow cytometry to select for events of spontaneous (partial) loss of either the two smallest LS chromosomes or two different core chromosomes. We determined the rate of spontaneous loss of the 'effector' LS chromosome in vitro at around 1 in 35 000 spores. In addition, a viable strain was obtained lacking chromosome 12, which is considered to be a part of the core genome. We also isolated strains carrying approximately 1-Mb deletions in the LS chromosomes and in the dispensable core chromosome. The large core chromosome 1 was never observed to sustain deletions over 200 kb. Whole-genome sequencing revealed that some of the sites at which the deletions occurred were the same in several independent strains obtained for the two chromosomes tested, indicating the existence of deletion hotspots. For the core chromosome, this deletion hotspot was the site of insertion of the marker used to select for loss events. Loss of the core chromosome did not affect pathogenicity, whereas loss of the effector chromosome led to a complete loss of pathogenicity.
Project description:The Fusarium solani species complex (FSSC) has been studied intensively but its association with legumes, particularly under European agro-climatic conditions, is still poorly understood. In the present study, we investigated phylogenetic relationships and aggressiveness of 79 isolates of the FSSC collected from pea, subterranean clover, white clover and winter vetch grown under diverse agro-climatic and soil conditions within Temperate and Mediterranean Europe. The isolates were characterized by sequencing tef1 and rpb2 loci and by greenhouse aggressiveness assays. The majority of the isolates belonged to two lineages: the F. pisi comb. nov. lineage (formerly F. solani f. sp. pisi) mainly accommodating German and Swiss isolates, and the Fusisporium (Fusarium) solani lineage accommodating mainly Italian isolates. Based on the results of aggressiveness tests on pea, most of the isolates were classified as weakly to moderately aggressive. In addition, using one model strain, 62 accessions of 10 legume genera were evaluated for their potential to host F. pisi, the species known mainly as a pathogen of pea. A total of 58 accessions were colonized, with 25 of these being asymptomatic hosts. These results suggest a broad host range for F. pisi and challenge the forma specialis naming system in Fusarium.