Project description:Belonging to the Carmovirus family, Turnip crinkle virus (TCV) is a positive-strand RNA virus that can infect Arabidopsis. Most Arabidopsis ecotypes are highly susceptible to TCV, except for the TCV resistant line Di-17 derived from ecotype Dijon. Previous studies showed that many of the stress related genes have changed significantly after TCV infection. Besides the virus-triggered genes, small RNAs also play critical roles in plant defense by triggering either transcriptional and/or post-transcriptional gene silencing. In this study, TCV-infected wildtype Arabidopsis thaliana and dcl1-9 mutant plants were subjected to transcriptome and small RNA analysis to investigate the role of DCL1 in virus defense network.
Project description:Small RNA libraries of wildtype Arabidopsis thaliana and its mutant Dicer-like 1 (Dcl1) were constructed and sequenced for miRNA identification and expression analysis. The mutant data was used to validate novel miRNA predictions (from miRCat2 (Paicu et al. 2017), miRCat (Moxon et al. 2008), miRPlant (An et al. 2014) and miReap (http://mireap.sourceforge.net/)), by calculating the log fold change between the mutant and the wildtype samples.
Project description:Belonging to the Carmovirus family, Turnip crinkle virus (TCV) is a positive-strand RNA virus that can infect Arabidopsis. Most Arabidopsis ecotypes are highly susceptible to TCV, except for the TCV resistant line Di-17 derived from ecotype Dijon. Previous studies showed that many of the stress related genes have changed significantly after TCV infection. Besides the virus-triggered genes, small RNAs also play critical roles in plant defense by triggering either transcriptional and/or post-transcriptional gene silencing. In this study, TCV-infected wildtype Arabidopsis thaliana and dcl1-9 mutant plants were subjected to transcriptome and small RNA analysis to investigate the role of DCL1 in virus defense network.
Project description:The Arabidopsis genome contains a highly complex and abundant population of small RNAs, and many of the endogenous siRNAs are dependent on RNA-DEPENDENT RNA POLYMERASE 2 (RDR2) for their biogenesis. By analyzing an rdr2 loss-of-function mutant using two different parallel sequencing technologies, MPSS and 454, we characterized the complement of miRNAs expressed in Arabidopsis inflorescence to considerable depth. Nearly all known miRNAs were enriched in this mutant and we identified 13 new miRNAs, all of which were relatively low abundance and constitute new families. Trans-acting siRNAs (ta-siRNAs) were even more highly enriched. Computational and gel blot analyses suggested that the minimal number of miRNAs in Arabidopsis is approximately 155. The size profile of small RNAs in rdr2 reflected enrichment of 21-nt miRNAs and other classes of siRNAs like ta-siRNAs, and a significant reduction in 24-nt heterochromatic siRNAs. Other classes of small RNAs were found to be RDR2-independent, particularly those derived from long inverted repeats and a subset of tandem repeats. The small RNA populations in other Arabidopsis small RNA biogenesis mutants were also examined; a dcl2/3/4 triple mutant showed a similar pattern to rdr2, whereas dcl1-7 and rdr6 showed reductions in miRNAs and ta-siRNAs consistent with their activities in the biogenesis of these types of small RNAs. Deep sequencing of mutants provides a genetic approach for the dissection and characterization of diverse small RNA populations and the identification of low abundance miRNAs. Keywords: small RNA sequences generated by 454 sequencing
Project description:We examined the changes in gene expression in Arabidopsis thaliana grown under arsenate stress. The transcriptional profiling reveals antioxidant activity and repression of the phosphate starvation response. Keywords: dual label, stress response
Project description:Post-transcriptional gene regulation plays a significant role in the response to Pi starvation. Here, we utilized advances in next-generation sequencing technology to examine changes in transcriptional control, RNA association with translating ribosomes in 14-day-old Arabidopsis seedlings subjected to 7 days of Pi starvation.