Project description:We describe a series of computational pipelines for the in silico analysis of small RNAs (sRNA) produced in response to viral infections in plants. Our workflow is primarily focused on the analysis of sRNA populations derived from known or previously undescribed viruses infecting host plants. Furthermore, we provide an additional pipeline to examine host-specific endogenous sRNAs activated or specifically expressed during viral infections in plants. We present some key points for a successful and cost-efficient processing of next generation sequencing sRNA libraries, from purification of high quality RNA to guidance for library preparation and sequencing strategies. We report a series of free available tools and programs as well as in-house Perl scripts to perform in-house sRNA-seq data mining. A multi-step analysis pipeline is extensively detailed so previous bioinformatic background is not required, but experience with basic Unix commands is desirable.
Project description:We investigated changes in gene expression in rice plants exposed to RDV to gain some insight into the fundamental physiological and biochemical changes that are induced by viral infection, in the hope of finding clues that might help to control the viral disease. An analysis, using microarrays, of gene expression in rice plants infected with Rice dwarf virus revealed significant decreases in levels of expression of genes that are involved in the formation of cell walls, reflecting the stunted growth of diseased plants. The expression of plastid-related genes was also suppressed, as anticipated from the white chlorotic appearance of infected leaves. By contrast, the expression of defense- and stress-related genes was enhanced after viral infection. Keywords: disease state analysis
Project description:In response to infection, viral genomes are processed by Dicer-like (DCL) ribonuclease proteins into viral small RNAs (vsRNAs) of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some group of viruses. However, nothing is known for members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, the population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV), a member of the genus Polerovirus, family Luteoviridae, is characterized.Deep sequencing of small RNAs (sRNAs) from CLRDV-infected cotton leaves was performed. Results showed 21-nt to 24-nt long vsRNAs matching all the viral genome, with a higher frequency of matches in the 3â region. Equivalent amounts of sense and antisense vsRNAs were found, and the 22-nt long small RNA class was the most prominent one. Looking for cotton Dcl transcripts levels during infection, we could observe that Dcl4 seems to be up-regulated, while Dcl2 seems to be down-regulated.This is the first report on the profile of sRNAs coming from a plant infected with a member of the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAsOur results indicate that secondary structures of the viral RNAs are not the main source of the viRNAs observed, as suggested for other viruses. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpected high accumulation of 22-nt viRNAvsRNAs are discussed. CLRDV is the causal agent of worldwide cotton pathology named Cotton blue disease. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases.
Project description:au07-02_trv - arabidopsis transcriptome microarray from virus infected leafs. - mRNA expression profile in virus-infected Arabidopsis. - mRNA and microRNA expression profile in virus-infected leafs of Arabidopsis. Keywords: normal vs disease comparison
Project description:In response to infection, viral genomes are processed by Dicer-like (DCL) ribonuclease proteins into viral small RNAs (vsRNAs) of discrete sizes. vsRNAs are then used as guides for silencing the viral genome. The profile of vsRNAs produced during the infection process has been extensively studied for some group of viruses. However, nothing is known for members of the economically important family Luteoviridae, a group of phloem-restricted viruses. Here, the population of vsRNAs from cotton plants infected with Cotton leafroll dwarf virus (CLRDV), a member of the genus Polerovirus, family Luteoviridae, is characterized.Deep sequencing of small RNAs (sRNAs) from CLRDV-infected cotton leaves was performed. Results showed 21-nt to 24-nt long vsRNAs matching all the viral genome, with a higher frequency of matches in the 3M-CM-"M-BM-^@M-BM-^Y region. Equivalent amounts of sense and antisense vsRNAs were found, and the 22-nt long small RNA class was the most prominent one. Looking for cotton Dcl transcripts levels during infection, we could observe that Dcl4 seems to be up-regulated, while Dcl2 seems to be down-regulated.This is the first report on the profile of sRNAs coming from a plant infected with a member of the family Luteoviridae. Our sequence data strongly suggest that virus-derived double-stranded RNA functions as one of the main precursors of vsRNAsOur results indicate that secondary structures of the viral RNAs are not the main source of the viRNAs observed, as suggested for other viruses. Judging by the profiled size classes, all cotton DCLs might be working to silence the virus. The possible causes for the unexpected high accumulation of 22-nt viRNAvsRNAs are discussed. CLRDV is the causal agent of worldwide cotton pathology named Cotton blue disease. Our results are an important contribution for understanding the molecular mechanisms involved in this and related diseases. Total RNA obtained from leaves of the cotton plant 5 days post-infection with Cotton leafrol dawrf virus (CLRDV) compared to not-infected control.
Project description:Aster yellows phytoplasma strain Hyd35 (16SrI-B) in micropropagated periwinkle shoots in collection was used to produce infected plants in pots that were separated according to the diverse symptomatology i.e. phyllody and witches’ broom. Small RNA high-throughput sequencing (HTS) was then used to determine the small RNA pattern of these plants. Bioinformatics analysis revealed the presence of expression changes of different miRNA classes and the presence of phytoplasma derived small RNAs. These results could complement previous studies and serve as a starting point for small RNA omics in phytoplasma research