Project description:Purpose:we aimed to demonstrate the effects of cycloastragenol on the different plant signaling mechanisms and analyze microRNAomic responses in order to demonstrate its potential as a new key molecule to help plants overcome different environmental stresses. Methods: smallRNA-seq was employed to give a quantitative profile of microRNA expression and to identify new micro RNAs and in treated and non-treated A. thaliana calli. We sequenced two cDNA libraries developed from A. thaliana (wild type Col-0) calli, one non-treated and the other is treated with 1µM cycloatragenol. Reads were filtered, mapped, aligned and then compared to the reference annotation (miRBase database). Clean data was analyzed using different software in order to identify differentilly expressed miRNAs and their target genes. Results were validated by qRT-PCR using TaqMan and SYBER green assays. Results: We mapped more than 31 and 30 million tags from, respectively, control and CAG-treated samples. After filtration and mapping, a total of 273 known micro RNAs, 298 novels expressed miRNAs and 6160 target genes were identified, among which a total of 119 miRNAs and 961 target genes showed differential expression between control and treated sample with a p value < 0.05. Nine miRNAs, which have been chosen randomly, were validated with qRT-PCR. SmallRNA-seq data had a linear relationship with qRT-PCR for a goodness of fit (R2) of 0.938.
Project description:microRNA dysregulation is a common feature of cancer cells, but the complex roles of microRNAs in cancer are not fully elucidated. Here we used functional genomics to identify oncogenic microRNAs in non-small cell lung cancer and to evaluate their impact on response to EGFR targeting therapy. Our data demonstrate that microRNAs with an AAGUGC-motif in their seed-sequence increase both cancer cell proliferation and sensitivity to EGFR inhibitors. Global transcriptomics, proteomics and target prediction resulted in the identification of several tumor suppressors involved in the G1/S transition as targets of AAGUGC-microRNAs. The clinical implications of our findings were evaluated by analysis of public domain data supporting the link between this microRNA seed-family, their tumor suppressor targets and cancer cell proliferation. In conclusion we propose that AAGUGC-microRNAs are an integral part of an oncogenic signaling network, and that these findings have potential therapeutic implications, especially in selecting patients for EGFR-targeting therapy.
Project description:Purpose: we aimed to demonstrate the effects of Cycloastragenol on the different plant signaling mechanisms and analyze genome-wide transcriptional responses in order to demonstrate its potential as a new key molecule to help plants overcome different environmental stresses. Methods: RNA-seq was employed to assess transcriptional profiles in treated and non-treated A. thaliana calli. We sequenced two cDNA libraries developed from A. thaliana (wild type Col-0) calli treated with 1µM Cycloatragenol and without. The sequence reads that was filtered, were mapped, aligned and then compared to the reference annotation (the known genes of A. thaliana genome) using Cufflinks tools. Clean data was analyzed using CPC software and results were validated by qRT-PCR using TaqMan and SYBER green assays. Results: We mapped around 63 and 70 million sequence reads from, respectively, control and CAG-treated samples. After filtration and mapping about 21 thousands genes corresponding to an average of 34 thousands transcripts, for each sample were identified. 1045 genes showed differential expression between control and treated sample with a p value < 0.05. Seven genes, which have been chosen randomly, were validated with qRT-PCR. RNA-seq data had a linear relationship with qRT-PCR for a goodness of fit (R2) of 0.959.
Project description:microRNA dysregulation is a common feature of cancer cells, but the complex roles of microRNAs in cancer are not fully elucidated. Here we used functional genomics to identify oncogenic microRNAs in non-small cell lung cancer and to evaluate their impact on response to EGFR targeting therapy. Our data demonstrate that microRNAs with an AAGUGC-motif in their seed-sequence increase both cancer cell proliferation and sensitivity to EGFR inhibitors. Global transcriptomics, proteomics and target prediction resulted in the identification of several tumor suppressors involved in the G1/S transition as targets of AAGUGC-microRNAs. The clinical implications of our findings were evaluated by analysis of public domain data supporting the link between this microRNA seed-family, their tumor suppressor targets and cancer cell proliferation. In conclusion we propose that AAGUGC-microRNAs are an integral part of an oncogenic signaling network, and that these findings have potential therapeutic implications, especially in selecting patients for EGFR-targeting therapy.
Project description:Small RNA sequences from Arabidopsis thaliana Col-0 inflorescence tissues of three biological replicates. The data were analyzed to identify non-templated nucleotides in Arabidopsis small RNAs.
Project description:Small RNA diversity and function has been widely characterized in various tissues of the sporophytic generation of the angiosperm model Arabidopsis thaliana. In contrast, there is limited knowledge about small RNA diversity and their roles in developing male gametophytes. We thus carried out small RNA sequencing on RNA isolated from four stages of developing Arabidopsis thaliana pollen.
Project description:Plants evolved an array of disease resistance genes (R genes) to fight pathogens. In the absence of pathogen infection, NBS-LRR genes, which comprise a major subfamily of R genes, are suppressed by a small RNA cascade involving microRNAs (miRNAs) that trigger the biogenesis of phased siRNAs (phasiRNAs) from R gene transcripts. However, whether or how R genes influence small RNA biogenesis is unknown. In this study, we isolated a mutant with global defects in the biogenesis of miRNAs and phasiRNAs in Arabidopsis thaliana and traced the defects to the over accumulation and nuclear localization of an R protein SNC1. We showed that nuclear SNC1 represses the transcription of miRNA and phasiRNA loci, probably through the transcriptional corepressor TPR1. Intriguingly, nuclear SNC1 reduces the accumulation of phasiRNAs from three source R genes and concomitantly, the expression of a majority of the ~170 R genes was up-regulated. Taken together, this study reveals a new R gene-miRNA-phasiRNA regulatory module that regulates plants' growth-defense trade-off.
Project description:MicroRNAs (miRNAs) and small interfering RNAs (siRNAs) are produced in diverse species and control gene expression and epigenetic regulation. Although physiological and developmental roles of miRNAs and siRNAs have been extensively studied in plants and animals, expression diversity and evolution of miRNAs and siRNAs in closely related species are poorly understood. Here we report comprehensive analyses of miRNA expression and siRNA distribution in two closely related species (Arabidopsis thaliana and A. arenosa), a natural allotetraploid (A. suecica), and two resynthesized allotetraploid lines (F1 and F7) derived from A. thaliana and A. arenosa. The siRNA populations present in A. thaliana were maintained in resynthesized allotetraploids and A. suecica. Although miRNA sequences were highly conserved, their expression patterns were highly variable between the allotetraploids and their progenitors. Significantly, many miRNAs were nonadditively expressed in the allotetraploids relative to the parents and preferentially degraded A. thaliana or A. arenosa targets. Stable inheritance of parental siRNAs in allopolyploids helps maintain genome stability in response to M-bM-^@M-^\genomic shockM-bM-^@M-^], whereas expression diversity of miRNAs and their target preference lead to interspecies variation in gene expression, growth, and development. NOTE: sff files unavailable for Samples AaL and F1L. 10 samples examined: Arabidopsis thaliana leaf, flower, Arabidopsis arenosa leaf and flower, F1 synthetic allopolyploid leaf and flower, F7 synthetic allopolyploid leaf and flower, Arabidopsis suecica leaf and flower. To determine small RNA profiles in Arabidopsis allotetraploids and their progenitors, we made 10 small RNA libraries from rosette leaves (L) and flower buds (F) in five lines, A. thaliana, A. arenosa, Allo(F1), Allo733(F7), and A. suecica. To examine expression of small RNAs among related species and their hybrids, we employed miRNA microarrays and compared small RNA levels.
Project description:High-throughput sequencing of Arabidopsis thaliana endogenous small RNAs by 454 pyrosequencing. Keywords: high-throughput sequencing