Project description:Genes responsive to brassinosteroid were fully investigated using bil1-1D/bzr1-1D mutant which shows constitutive/enhanced response to brassinosteroid. Bil1-1D plants and wild type were treated with Brz (brasinazole) followed with brassinolide or DMSO, respectively.
Project description:We found that auxin stimulates gene expression of DWF4, which encodes a rate-dertermining step in brassinosteroid biosynthesis pathways. This increased gene expressioin subsequently led to elevation of the biosynthetic flux in Arabidopsis roots. To determine the list of genes that are regulated by auxin-synthesizing brassinosteroids, we challenged Arabidopsis seedlings with either auxin only or auxin plus brassinosteroid biosynthetic inhibitor brassinazole. Keywords: Hormone treatment
Project description:We were interested in investigating the transcriptome responses to exogenous applications of brassinosteroid hormone when Arabidopsis seedlings are pre-stressed with a reactive oxygen species, hydrogen peroxide. We were interested in seeing which subsets of BR-responsive gene transcripts were most affected and how BR-responsive gene transcripts responded to increasing concentrations of hydrogen peroxide both as a whole and individually.
Project description:We were interested in investigating the transcriptome responses to exogenous applications of brassinosteroid hormone when Arabidopsis seedlings are pre-stressed with a reactive oxygen species, hydrogen peroxide. We were interested in seeing which subsets of BR-responsive gene transcripts were most affected and how BR-responsive gene transcripts responded to increasing concentrations of hydrogen peroxide both as a whole and individually. Liquid culture Arabidopsis seedlings are grown under standard conditions. Hydrogen peroxide is added at various concentrations to pre-stress the seedlings. Following this pretreatment, the seedlings are then treated with brassinosteroid (BR) hormone (epi-brassinolide, BL). Following this treatment, seedlings are harvested and total RNA is extracted for genome-wide transcriptome analysis.
Project description:Brassinosteroids (BRs) are a class of class of phytohormones with important roles in regulating physiological and developmental processes. Small RNAs, including small interfering RNAs and microRNAs (miRNAs), are non-protein coding RNAs that regulate gene expression at the transcriptional and post-transcriptional levels. However, the roles of small RNAs in BR response have not been studied well. In this study, we aimed to identify BR-responsive small RNA clusters and miRNAs in Arabidopsis. In addition, the effect of BR-responsive small RNAs on their transcripts and target genes were examined. Small RNA libraries were constructed from control and epibrassinolide-treated seedlings. After sequencing the small RNA libraries, differentially expressed small RNA clusters were identified by examining the expression levels of small RNAs in 100-nt bins of Arabidopsis genome. To identify the BR-responsive miRNAs, the expression levels of all the annotated mature miRNAs, registered in miRBase, were analyzed. Previously published RNA-seq data were utilized to monitor the BR-responsive expression patterns of differentially expressed small RNA clusters and miRNA target genes. In results, 38 BR-responsive small RNA clusters, including 30 down-regulated and eight up-regulated clusters, were identified. These differentially expressed small RNA clusters were from miRNA loci, transposons, protein-coding genes, pseudo genes and others. Of these, a transgene, BRI1, accumulates small RNAs, which are not found in the wild type. Small RNAs in this transgene are up-regulated by BRs while BRI1 mRNA is down-regulated by BRs. By analyzing the expression patterns of mature miRNAs, we have identified BR-repressed miR398a-5p and BR-induced miR156g. Although miR398a-5p is down-regulated by BRs, its predicted targets were not responsive to BRs. However, SPL3, a target of BR-inducible miR156g, is down-regulated by BRs. BR-responsive small RNAs and miRNAs identified in this study will provide an insight into the role of small RNAs in BR responses in plants. Especially, we suggest that miR156g/SPL3 module might play a role in BR-mediated growth and development in Arabidopsis.
Project description:The effects of brassinosteroid signaling on shoot and root development have been characterized in great detail but did not identify a simple consistent positive or negative impact on a basic cellular parameter. Here we combined digital 3D single-cell shape analysis and single-cell mRNA sequencing to characterize root meristems and mature root segments of brassinosteroid-blind mutants and wildtype. These data demonstrate that brassinosteroid signaling neither affects cell volume nor cell proliferation capacity. Instead, brassinosteroid signaling is essential for the precise orientation of cell division planes and the extent and timing of anisotropic cell expansion. Moreover, we found that the cell-aligning effects of brassinosteroid signaling can propagate to normalize the anatomy of both adjacent and distant brassinosteroid-blind cells through non-cell-autonomous functions, which are sufficient to restore growth vigor. Finally, single-cell transcriptome data discern directly brassinosteroid-responsive genes from genes that can react non-cell-autonomously and highlight arabinogalactans as sentinels of brassinosteroid-dependent anisotropic cell expansion.
Project description:We report global gene expression profilies of Brassinosteroid related Arabidopsis mutants in response to dehydration and fixed-carbon starvation stresses by RNA-seq