Project description:Fungal interactions with plant roots, either beneficial or detrimental, have a major impact on agriculture and ecosystems1. The soil inhabiting ascomycete Fusarium oxysporum (Fo) constitutes a species complex of worldwide distribution causing vascular wilt in more than a hundred different crops2,3. Individual isolates of the fungus exhibit host-specific pathogenicity, determined by proteinaceous effectors termed secreted in xylem (SIX)4,5. However, such isolates can also colonize roots of non-host plants asymptomatically as endophytes, or even protect the plant against pathogenic isolates6,7. The molecular determinants of multi-host plant colonization are currently unknown. Here, we identified a set of fungal effectors termed ERCs (Early Root Compatibility effectors), which are secreted during early biotrophic growth of Fo on both host and non-host plants. In contrast to SIX effectors, which are encoded on lineage specific (LS) genomic regions5,8, ERCs are encoded on core genomic regions and broadly conserved across the Fo species complex. Targeted deletion of ERC genes in pathogenic Fo isolate resulted in reduced virulence on the host plant and rapid activation of plant immune responses, while in a non-pathogenic isolate it led to impaired root colonization and loss of biocontrol ability. Strikingly, some ERCs also contribute to Fo infection on the non-vascular land plant Marchantia polymorpha. Our results reveal an evolutionarily conserved mechanism for multi-host colonization by root infecting fungi.
Project description:Fusarium oxysporum is one of the most common species causing soybean root rot and seedling blight in the U.S. In a recent study, significant variation in aggressiveness was observed among isolates of F. oxysporum collected from roots in Iowa, ranging from highly pathogenic to weakly or non-pathogenic isolates. In the present work, a RNA-seq-based analysis was used for the first time to investigate the molecular aspect of the interaction of a partially resistant soybean genotype with non-pathogenic/pathogenic isolates of F. oxysporum at 72 and 96 hours post inoculation (hpi). Markedly different gene expression profiles were observed in compatible and incompatible host-pathogen combinations. A peak of differentially expressed genes (DEGs) was observed at 72 hpi in soybean roots in response to both isolates, although the number of DEGs was about eight times higher for the pathogenic isolate compared to the non-pathogenic one (1,659 vs. 203 DEGs, respectively). Furthermore, not only the number of genes, but also the magnitude of induction was much greater in response to the pathogenic isolate. This response included a stronger activation of many well-known defense-related genes, and several genes involved in ethylene biosynthesis and signalling, transcription factors, secondary and sugar metabolism. In addition, 1130 fungal genes were differentially expressed between the F. oxysporum isolates in planta during the infection process. Interestingly, 10% of these genes encode plant cell-wall degrading enzymes, reactive oxygen species-related enzymes and fungal proteins involved in primary metabolic pathways. Such information may be useful in the development of new methods of broadening resistance of soybean to F. oxysporum, including the silencing of important fungal genes, and also to understand the molecular basis of soybean-F. oxysporum interactions. Soybean seedlings mRNA profiles inoculated with a non-pathogenic and pathogenic isolates of F. oxysporum and collected at 72 and 96 hpi, were generated using Illumina HiSeq 2500. Control seedlings were also included for each time of inoculation. Three biological replicates were considered for each condition, 18 samples in total.
Project description:We studied microRNA expression levels from serum of postmenopausal women with osteoporosis by investigating the anti-osteoporotic treatment denosumab for a period of 2 years in a longitudinal study. Serum RNA was extracted and subject to small RNA sequencing on an Illumina HiSeqV4 SR50 using 50bp, single end reads. After mapping against GRCh38.p12 provided by Ensembl and miRBase v22.1 differential expression analysis was undertaken with edgeRv3.28 using a quasi-likelihood negative binomial generalized log-linear model. We identified a panel of altered small non-coding RNAs between 3 different time points for all patients.
Project description:Fusarium oxysporum is one of the most common species causing soybean root rot and seedling blight in the U.S. In a recent study, significant variation in aggressiveness was observed among isolates of F. oxysporum collected from roots in Iowa, ranging from highly pathogenic to weakly or non-pathogenic isolates. In the present work, a RNA-seq-based analysis was used for the first time to investigate the molecular aspect of the interaction of a partially resistant soybean genotype with non-pathogenic/pathogenic isolates of F. oxysporum at 72 and 96 hours post inoculation (hpi). Markedly different gene expression profiles were observed in compatible and incompatible host-pathogen combinations. A peak of differentially expressed genes (DEGs) was observed at 72 hpi in soybean roots in response to both isolates, although the number of DEGs was about eight times higher for the pathogenic isolate compared to the non-pathogenic one (1,659 vs. 203 DEGs, respectively). Furthermore, not only the number of genes, but also the magnitude of induction was much greater in response to the pathogenic isolate. This response included a stronger activation of many well-known defense-related genes, and several genes involved in ethylene biosynthesis and signalling, transcription factors, secondary and sugar metabolism. In addition, 1130 fungal genes were differentially expressed between the F. oxysporum isolates in planta during the infection process. Interestingly, 10% of these genes encode plant cell-wall degrading enzymes, reactive oxygen species-related enzymes and fungal proteins involved in primary metabolic pathways. Such information may be useful in the development of new methods of broadening resistance of soybean to F. oxysporum, including the silencing of important fungal genes, and also to understand the molecular basis of soybean-F. oxysporum interactions.
Project description:Investigation of whole genome gene expression level changes in leaves of susceptible (MM106) or resistant (ME010) apple genotypes either non-inoculated, inoculated with the wild type strain of Erwinia amylovora (CFBP1430) or the non-pathogenic mutant strain PMV6023. The mutant strain PMV6023 is affected in the biosynthesis of the type 3 secretion system delivering bacterial effectors into apple cells. Leaves were harvested for RNA extraction before inoculation, 6 hours and 24 hours after inoculation.