Project description:In seed plants, leaves are born on radial shoots but unlike shoots they are determinate dorsiventral organs made of flat lamina. YABBY genes are found only in seed plants and in all cases studied, are expressed primarily in lateral organs and in a polar manner. Despite their simple expression, Arabidopsis plants lacking all YABBY gene activities have a wide range of morphological defects in all lateral organs as well as the shoot apical meristem. Here we show that leaves lacking all YABBY activities are initiated as dorsiventral appendages but fail to properly activate lamina programs. In particular, the activation of most CIN-TCPs does not commence, SAM-specific programs are reactivated, and a marginal leaf domain is not established. Altered distribution of auxin signalling and the auxin efflux carrier PIN1, highly reduced venation, initiation of multiple cotyledons, and gradual loss of the SAM accompany these defects. We suggest that YABBY functions were recruited to mould modified shoot systems into flat plant appendages by translating organ polarity into lamina specific programs that include marginal auxin flow and activation a maturation schedule directing determinate growth.
Project description:Comparison of gene expression between shoots of root-wounded seedlings and shoots of control seedlings in Arabidopsis. We identified wounding-induced early (30 min) and late (360 min) root to shoot responsive genes (RtS).
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:Background: The unprecedented rise in atmospheric CO2 concentration and injudicious fertilization or heterogeneous distribution of Mg in the soil warrant further research to understand the synergistic and holistic mechanisms involved in the plant growth regulation. The objective of this work is to understand responses in plants along with interactive effect of elevated CO2 and Mg levels by comparing data on single stress with that of combined stresses. Results: This study investigated the influence of elevated CO2 (800 μL L−1) on physiological and transcriptomic profiles in Arabidopsis cultured in hydroponic media treated with 1 μM (low), 1000 μM (normal) and 10000 μM (high) Mg2+. Following 7-d treatment, elevated CO2 increased the shoot growth and chlorophyll content under both low and normal Mg supply, whereas root growth was improved exclusively under normal Mg nutrition. Notably, the effect of elevated CO2 on mineral homeostasis in both shoots and roots was less than that of Mg supply. Irrespective of CO2 treatment, high Mg increased leaf number but decreased root growth and absorption of P, K, Ca, Fe and Mn whereas low Mg increased the concentration of P, K, Ca and Fe in leaves. Elevated CO2 decreased the expression of genes related to cadmium response, cell redox homeostasis and lipid localization, but enhanced photosynthesis, signal transduction, protein phosphorylation, NBS-LRR disease resistance proteins and subsequently programmed cell death in low-Mg shoots. By comparison, elevated CO2 enhanced the response of lipid localization (mainly LTP transfer protein/protease inhibitor), endomembrane system, heme binding and cell wall modification in high-Mg roots. Some of these transcriptomic results are substantially in accordance with our physiological and/or biochemical analysis. Conclusions: Contrasting changes were found between roots and shoots with the shoot transcriptome being more severely affected by low Mg while the root transcriptome more affected by high Mg. Elevated CO2 had a greater effect on transcript response in low Mg-fed shoots as well as in high Mg-fed roots. The present findings broaden our current understanding on the interactive effect of elevated CO2 and Mg levels in the Arabidopsis, which may help to design the novel metabolic engineering strategies to cope with Mg deficiency/excess in crops under elevated CO2.
Project description:Transcriptional profiling of Arabidopsis leaves comparing mock-treated leaves with Botrytis cinerea infected leaves over a time-course (12 and 24 hrs).
Project description:A whole transcriptome (RNA-seq) study of Arabidopsis shoots under iron sufficient, deficient and resupply conditions was carried out to determine the genes that are iron-regulated in the shoots.
Project description:In seed plants, leaves are born on radial shoots but unlike shoots they are determinate dorsiventral organs made of flat lamina. YABBY genes are found only in seed plants and in all cases studied, are expressed primarily in lateral organs and in a polar manner. Despite their simple expression, Arabidopsis plants lacking all YABBY gene activities have a wide range of morphological defects in all lateral organs as well as the shoot apical meristem. Here we show that leaves lacking all YABBY activities are initiated as dorsiventral appendages but fail to properly activate lamina programs. In particular, the activation of most CIN-TCPs does not commence, SAM-specific programs are reactivated, and a marginal leaf domain is not established. Altered distribution of auxin signalling and the auxin efflux carrier PIN1, highly reduced venation, initiation of multiple cotyledons, and gradual loss of the SAM accompany these defects. We suggest that YABBY functions were recruited to mould modified shoot systems into flat plant appendages by translating organ polarity into lamina specific programs that include marginal auxin flow and activation a maturation schedule directing determinate growth. Four repeats of wild type 14 DAS plants were used to compare to fil,y3 and fil,y3,y5 mutants of similar age (two repeats of each)