Project description:The fungus Puccinia striiformis f.sp. tritici (PST) is the causal pathogen of stripe rust in wheat. New highly virulent PST races appeared at the beginning of this century and spread rapidly causing significant yield losses in wheat production worldwide. Race PST-08/21 was isolated in the UK in 2008 Yr1, Yr2, Yr3, Yr4, Yr6, Yr9, Yr17, Yr27, Yr32, YrRob, YrSol. We applied the RNAseq approach to refine the gene prediction in de novo assembled PST 08/21 contigs and to determine which genes are expressed during wheat infections. Total RNA was extracted from a pool of stripe rust infected wheat leaves and from two biological replicates of haustoria isolates.
Project description:Puccinia graminis f. sp. tritici is the cause of wheat stem rust. A microarray was designed from genes predicted from the P. graminis f. sp. tritici genome assembly, and gene expression measured for four conditions which include wheat or barley infecting growth stages initiated by urediniospores. mRNA was prepared from fresh urediniospores, uredinospores germinated for 24 hr, wheat seedlings infected with urediniospores for 8 days, and barley seedlings infected with urediniospores for 8 days. The asexual uredinial infection cycle on wheat produces additional urediniospores, which can start new cycles of wheat infection and are readily spread by aerial transport. This expression data is further described in Duplessis et al, Obligate Biotrophy Features Unraveled by the Genomic Analysis of the Rust Fungi, Melampsora larici-populina and Puccinia graminis f. sp. tritici
Project description:High plasticity of common wheat is attributed to the captured and polyploidization-promoted diversity. However, uncontrolled subgenome diversification can lead to hybrid conflict and dysgenesis, resulting in decreased diversity. How genomic diversity is maintained and interpreted to increase plasticity is unclear. By data-mining from the binding of 193 genome-wide trans-factors and genetic perturbations in common wheat, we identified LHP1 as a major regulator of subgenome-diversified defense genes, enhancer RNAs, and metabolite synthesis-related gene clusters via H3K27me3. Stripe rust infection leads to a global decrease in LHP1-mediated H3K27me3, deprivation of which enhances common wheat stripe rust resistance. We also revealed the consistency between subgenome diversity and population diversity, potentially promoted by LHP1, implying the recent diversification preferentially occurred in the captured subgenome-diversified regions regulated by LHP1. Thus, common wheat benefitted from multi-faced role of LHP1 in promoting sequence diversity and repressing subgenome-diversified defenses; this constraint is eliminated by pathogen infections, enabling timely release and fixation of favorable variations, conferring the evolutionary advantage and high plasticity of common wheat.
Project description:The RNA sequencing analysis was undertaken to investigate the transcriptomic changes in adult wheat inoculated with Puccinia graminis f. sp. tritici the causal agent of stem rust disease. The project firstly aims to compare gene expression in one susceptible wheat line with two wheat lines exhibiting adult plant resistance to the stem rust. Secondly, the project aims to examine the temporal changes in gene expression in wheat after inoculation. Wheat plants was grown until maturity under greenhouse conditions. Plants were inoculated with Puccinia graminis f. sp. tritici and the flag leaf sheath sampled for RNA sequencing. The project aims to give essential insight into the adult plant resistance response in wheat to Puccinia graminis f. sp. tritici inoculation.
Project description:Puccinia graminis f. sp. tritici is the cause of wheat stem rust. A microarray was designed from genes predicted from the P. graminis f. sp. tritici genome assembly, and gene expression measured for four conditions which include wheat or barley infecting growth stages initiated by urediniospores. mRNA was prepared from fresh urediniospores, uredinospores germinated for 24 hr, wheat seedlings infected with urediniospores for 8 days, and barley seedlings infected with urediniospores for 8 days. The asexual uredinial infection cycle on wheat produces additional urediniospores, which can start new cycles of wheat infection and are readily spread by aerial transport. This expression data is further described in Duplessis et al, Obligate Biotrophy Features Unraveled by the Genomic Analysis of the Rust Fungi, Melampsora larici-populina and Puccinia graminis f. sp. tritici A total of 12 samples were analyzed, including three biological replicates of the four conditions.
Project description:Japonica rice cultivar Nipponbare was inoculated with wheat leaf rust (Puccinia triticina f. sp. tritici, non-host pathogen to rice) to compare gene expression profiles with mock-inoculated controls. Although eventually failed in invasion, leaf rust induced a set of rice genes that were distinctally up-regulated, some of those were confirmed by quantitative real-time PCR assays.
Project description:Wheat leaf rust is a serious fungal disease of wheat that causes annual losses and necessitates using fungicides for effective disease management. It is caused by Puccinia triticina which spreads by means of airborne urediniospores. When these germinate on the leaf surface, they form germ-tubes which enter the leaf through open stomates. Spores and germ-tubes represent the first fungal structures that the host can perceive during a rust infection. They therefore contain proteins that could potentially trigger early host defense responses. Using 2-DE to separate this proteome, we produced gels containing 173 spots in the pI range of 4-7 and identified 123 proteins. These were predominantly proteins involved in metabolic and cellular processes, but with a large number (77%) of novel proteins that could not be identified through homology matching Twenty four of these showed no homology to wheat sequences, making them good candidate PAMPs.
Project description:Puccinia graminis f.sp. tritici (Pgt), the causal agent of stem rust disease in wheat, is one of the most destructive pathogens and can cause severe yield losses. Here, we utilize Hi-C sequencing technology to scaffold and phase the haplotypes for the genome assembly of a US Pgt isolate 99KS76A-1.