Project description:In compatible interactions, biotrophic microbial phytopathogens rely on the supply of carbon and nitrogen assimilates by the colonized host tissue. Successful biotrophs need to reprogram host metabolism, which also involves the stimulation of assimilate export from living host cells into the plant-pathogen interface at the infection site. In rice and cassava, SWEET sucrose transporters, are induced by bacterial TAL (transcriptional activator-like) effectors to establish compatibility. A pathogen-specific transcriptional induction of SWEET transporters has also been observed in Arabidopsis leaves upon microbial challenge. Here, we have assessed the question, whether the phloem localized AtSWEET11 and AtSWEET12 transporters represent susceptibility factors in the interaction of Arabidopsis with the fungal hemibiotroph Colletotrichum higginsianum (Ch). Compared to wild type, sweet11/sweet12 double mutants exhibited priming of the SA pathway in mock conditions. To investigate transcriptional changes in C. higgsinanum infected leaves, five-week old Arabidopsis plants were spray infected with 2 Mio. conidia/ ml 1h before lights off and fully expanded leaves of wild type Col-0 and the sweet11/sweet12 double mutant were harvested in three situations: 1) immediately before treatment, 2) from mock treated plants (sprayed with water) at 2.5 days post treatment and 3) from C. higginsianum inoculated leaves during biotrophic colonization at 2.5 days post treatment
Project description:In compatible interactions, biotrophic microbial phytopathogens rely on the supply of carbon and nitrogen assimilates by the colonized host tissue. Successful biotrophs need to reprogram host metabolism, which also involves the stimulation of assimilate export from living host cells into the plant-pathogen interface at the infection site. In rice and cassava, SWEET sucrose transporters, are induced by bacterial TAL (transcriptional activator-like) effectors to establish compatibility. A pathogen-specific transcriptional induction of SWEET transporters has also been observed in Arabidopsis leaves upon microbial challenge. Here, we have assessed the question, whether the phloem localized AtSWEET11 and AtSWEET12 transporters represent susceptibility factors in the interaction of Arabidopsis with the fungal hemibiotroph Colletotrichum higginsianum (Ch). Compared to wild type, sweet11/sweet12 double mutants exhibited priming of the SA pathway in mock conditions.
Project description:Transcriptome of 4 developmental stages of Colletotrichum higginsianum during infection of Arabidopsis thaliana 3 biological replicates per stage. The four stages are : in vitro apressoria (VA), penetrating apressoria (AP), Biotrophic hyphea from the biotrophic phase (BH) and the switch from biotrophic hyphea to necrotrophic phase(SW). Each biological replicate of the last three stages, the in planta stages, was two fold deeper due to plant contamination (Arabidopsis thaliana)
Project description:Here we describe the identification and regulation of a novel dsRNA virus in Colletotrichum higginsianum. High throughput sequencing of small RNAs and strand-specific RNA-seq was performed on single gene knock-out mutants created for each RNAi component gene: rdr1, rdr2, rdr3, dcl1, dcl2, ago1, and ago2, and the double mutant: ∆dcl1∆dcl2. De novo assembly of the ∆dcl1 RNA-seq data identified two contigs that represented the forward and reverse strands of an uncharacterized dsRNA virus, designated here as Colletotrichum higginsianum non-segmented dsRNA virus 1 (ChNRV1). We found increased presence of the viral RNA in the RNA-seq datasets of the ∆dcl1, ∆dcl1dcl2, and ∆ago1 strains, suggesting that these genes are required for control of the virus. We show that viral small RNAs co-immunoprecipitate with a 6xFLAG-3xHIS-tagged AGO1 protein by sequencing the small RNAs from immunoprecipitated fractions. Additionally, analyses of the small RNA datasets from the RNAi mutants revealed control of the virus through small RNA-mediated silencing required both AGO1 and DCL1.
Project description:Here we describe the identification and regulation of a novel dsRNA virus in Colletotrichum higginsianum. High throughput sequencing of small RNAs and strand-specific RNA-seq was performed on single gene knock-out mutants created for each RNAi component gene: rdr1, rdr2, rdr3, dcl1, dcl2, ago1, and ago2, and the double mutant: ∆dcl1∆dcl2. De novo assembly of the ∆dcl1 RNA-seq data identified two contigs that represented the forward and reverse strands of an uncharacterized dsRNA virus, designated here as Colletotrichum higginsianum non-segmented dsRNA virus 1 (ChNRV1). We found increased presence of the viral RNA in the RNA-seq datasets of the ∆dcl1, ∆dcl1dcl2, and ∆ago1 strains, suggesting that these genes are required for control of the virus. We show that viral small RNAs co-immunoprecipitate with a 6xFLAG-3xHIS-tagged AGO1 protein by sequencing the small RNAs from immunoprecipitated fractions. Additionally, analyses of the small RNA datasets from the RNAi mutants revealed control of the virus through small RNA-mediated silencing required both AGO1 and DCL1.
Project description:Here we describe the identification and regulation of a novel dsRNA virus in Colletotrichum higginsianum. High throughput sequencing of small RNAs and strand-specific RNA-seq was performed on single gene knock-out mutants created for each RNAi component gene: rdr1, rdr2, rdr3, dcl1, dcl2, ago1, and ago2, and the double mutant: ∆dcl1∆dcl2. De novo assembly of the ∆dcl1 RNA-seq data identified two contigs that represented the forward and reverse strands of an uncharacterized dsRNA virus, designated here as Colletotrichum higginsianum non-segmented dsRNA virus 1 (ChNRV1). We found increased presence of the viral RNA in the RNA-seq datasets of the ∆dcl1, ∆dcl1dcl2, and ∆ago1 strains, suggesting that these genes are required for control of the virus. We show that viral small RNAs co-immunoprecipitate with a 6xFLAG-3xHIS-tagged AGO1 protein by sequencing the small RNAs from immunoprecipitated fractions. Additionally, analyses of the small RNA datasets from the RNAi mutants revealed control of the virus through small RNA-mediated silencing required both AGO1 and DCL1.
Project description:The objective of this study was on the one hand to compare the transcriptional dynamics of mutualistic Colletotrichum tofieldiae and pathogenic Colletotrichum incanum during colonization of Arabidopsis roots and on the other hand also examine the corresponding host responses
