Project description:The shoots and roots of a plant respond differently to osmotic stress, as they have distinct functions and anatomical structures. Under conditions of high solute concentration, such as in saline soils or drought, water uptake by the roots is reduced, resulting in cellular dehydration. In this study, we performed transcriptional profiling of roots of Arabidopsis under osmotic stress conditions such as high salinity and drought using mRNA-Seq for the assessment of gene expression changes in roots of Arabidopsis. mRNA-Seq analysis showed that many differentially expressed genes showed differential expressions under both salt stress and drought stress conditions in roots and were distinct from aerial parts. We confirmed 68 transcription factor genes which is involved in osmotic stress signal transduction in roots and are connected tightly. Interestingly, well-known ABA-dependent and/or -independent osmotic stress-responsive genes were less increased in roots, indicating that osmotic stress response in roots might be regulated by stress pathways other than well-known pathways. We identified 26 osmotic stress-responsive genes, which have alternative splicing variant isoforms, showed distinct expression in roots under osmotic stress conditions from the mRNA-Seq analysis. Quantitative RT-PCR confirmed that alternative splicing variants, such as ANNAT4, MAGL6, TRM19, and CAD9, have differential expressions in roots under osmotic stress conditions, indicating that alternative splicing is an important regulatory mechanism in osmotic stress response in roots. Taken together, our study suggest that many transcription factor families are involved in osmotic stress response in roots and tightly connected each other. In addition, alternative splicing and function of alternative splicing variant isoforms are also important in osmotic stress response in roots. To understand the alternative splicing mechanism in roots, further study is necessary.
Project description:The goal of this project is to compare the primary metabolite profile in different tissue types of the model plant Arabidopsis thaliana. Specifically, plants were grown hydroponically under the long-day (16hr light/day) condition at 21C. Tissue samples, including leaves, inflorescences, and roots were harvest 4 1/2 weeks post sowing. Untargeted primary metabolites profiling was carried out using GCTOF.
Project description:Drought is an important environmental factor affecting plant growth and biomass production. Despite this importance, little is known on the molecular mechanisms regulating plant growth under water limiting conditions. The main goal of this work was to investigate, using a combination of growth and molecular profiling techniques, how Arabidopsis thaliana leaves adapt their growth to prolonged mild osmotic stress. Fully proliferating, expanding and mature leaves were harvested from plants grown on plates without (control) or with 25mM mannitol (osmotic stress) and compared to seedlings at stage 1.03.
Project description:Drought is an important environmental factor affecting plant growth and biomass production. Despite this importance little is known on the molecular mechanisms regulating plant growth under water limiting conditions. The main goal of this work was to investigate, using a combination of growth and molecular profiling techniques, how stress arrests CELl proliferation in Arabidopsis thaliana leaves upon osmotic stress imposition.
Project description:To identifiy osmotic stress responsive smRNAs, we used a deep-sequencing technique to profile small RNA populations in leaf and root tissues of plants under high osmotic stress and control conditions. We treated 30day-old plants with high osmotic stress and sampled leaves and roots from the same plant with 3 biologial replicates. Then, 3 replicates were pooled and total RNA was extracted and prepared for smRNA deep sequencing. After normalization and annotation, we selected potential osmotic stress responsive smRNAs.