Project description:RNA-seq of Arabidopsis wild-type and atsf3b145 mutant seedling. The protein AtSF3B145 is involved in a subset of gene expression regulation.
Project description:Diverse classes of RNA, ranging from small to long non-coding RNAs, have emerged as key regulators of gene expression, genome stability and defence against foreign genetic elements. Small RNAs modify chromatin structure and silence transcription by guiding Argonaute-containing complexes to complementary nascent RNA scaffolds and then mediating the recruitment of histone and DNA methyltransferases. In addition, recent advances suggest that chromatin-associated long non-coding RNA scaffolds also recruit chromatin-modifying complexes independently of small RNAs. These co-transcriptional silencing mechanisms form powerful RNA surveillance systems that detect and silence inappropriate transcription events, and provide a memory of these events via self-reinforcing epigenetic loops.
Project description:Plants growing under high-density (HD) conditions experience increased competition for water, nutrients, and light, possibly leading to changes in size, biomass, morphology, and productivity. However, no research has focused on the relationship between whole-genome expression patterns and growth density. Here, we performed whole-genome RNA sequencing to examine the gene expression patterns in Arabidopsis grown under low and high densities. Of the 20,660 detected genes, the expression levels of 98 were enhanced and 107 were repressed under HD growth. Further analysis revealed that changes in density influenced metabolism- and stimulus-related genes the most. Furthermore, HD growth led to a shade avoidance phenotype, represented by upward growth and a reduction in rosette leaves. Moreover, a cluster of glutaredoxin genes, GRXS3, 4, 5, 7, and 8, were significantly down-regulated under high density, suggesting that high density affects plant growth mainly by nitrate limitation.
Project description:Micro RNAs (miRNAs) are a class of small endogenous RNAs conserved in eukaryotic organisms including plants. They suppress gene expression post-transcriptionally in many different biological processes. Previously, we reported salinity-induced changes in gene expression in transgenic Arabidopsis thaliana plants that constitutively expressed a pea abscisic acid-responsive (ABR17) gene. In the current study, we used a microarray to investigate the role of miRNA-mediated post-transcriptional gene regulation in these same transgenic plants in the presence and absence of salinity stress. We identified nine miRNAs that were significantly modulated due to ABR17 gene expression, and seven miRNAs that were modulated in response to salt stress. The target genes regulated by these miRNAs were identified using starBase (sRNA target Base) Degradome analysis and through 5' RNA Ligase Mediated-Rapid Amplification of cDNA Ends (RLM-RACE). Our findings revealed miRNA:mRNA interactions comprising regulatory networks of Auxin Response Factor (ARF), ARGONAUTE 1, (AGO1), Dicer-like proteins 1 (DCL1), Squamosa Promoter Binding (SPB), NAC, APETALA 2 (AP2), Nuclear Factor-Y (NFY), RNA binding proteins, Arabidopsis thaliana vacuolar phyrophosphate 1 (AVP1) and Pentatricopetide repeat (PPR) in ABR17 transgenic A. thaliana, which control physiological, biochemical and stress signalling cascades due to the imposition of salt stress. Our results are discussed within the context of the effect of the transgene, ABR17, and the roles miRNA expression may play in mediating plant responses to salinity.
Project description:Micro RNAs (miRNAs) are a class of small endogenous RNAs conserved in eukaryotic organisms including plants. They suppress gene expression post-transcriptionally in many different biological processes. Previously, we reported salinity-induced changes in gene expression in transgenic Arabidopsis thaliana plants that constitutively expressed a pea abscisic acid-responsive (ABR17) gene. In the current study, we used a microarray to investigate the role of miRNA-mediated post-transcriptional gene regulation in these same transgenic plants in the presence and absence of salinity stress. We identified nine miRNAs that were significantly modulated due to ABR17 gene expression, and seven miRNAs that were modulated in response to salt stress. The target genes regulated by these miRNAs were identified using starBase (sRNA target Base) Degradome analysis and through 5' RNA Ligase Mediated-Rapid Amplification of cDNA Ends (RLM-RACE). Our findings revealed miRNA:mRNA interactions comprising regulatory networks of Auxin Response Factor (ARF), ARGONAUTE 1, (AGO1), Dicer-like proteins 1 (DCL1), Squamosa Promoter Binding (SPB), NAC, APETALA 2 (AP2), Nuclear Factor-Y (NFY), RNA binding proteins, Arabidopsis thaliana vacuolar phyrophosphate 1 (AVP1) and Pentatricopetide repeat (PPR) in ABR17 transgenic A. thaliana, which control physiological, biochemical and stress signalling cascades due to the imposition of salt stress. Our results are discussed within the context of the effect of the transgene, ABR17, and the roles miRNA expression may play in mediating plant responses to salinity. In this miRNA-microarray experiment, a total of 4 samples were analyzed with their 3 biological replicates. Two samples, WT and ABR17 control (without salt treatment), were used as reference controls.