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 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. Total RNAs were extracted using Trizol method from vegetative part of seedlings at stage 1.03 and leaves that are fully proliferating, expanding or mature. All plants were grown in vitro on medium without (0mM) or with mannitol (25mM) in three independent biological experiments. Each sample was pooled from multiple plants and multiple plates in one experiment. RNA samples were submitted to ATH1 array hybridization.
Project description:Genome-wide transcriptome analysis of Arabidopsis thaliana was performed to understand the role of auxin in the response of leaf growth to osmotic stress. We studied transcriptional changes in proliferating leaves of the seedlings grown in vitro on control medium, medium supplemented with 25mM mannitol, 0.1μM NAA and 0.1μM NAA + 25mM mannitol.
Project description:Environmental conditions contributing to abiotic stresses such as drought and salinity result in large annual economic losses around the world. As sessile organisms, plants cannot escape the environmental stresses they encounter, but instead must adapt to survive. Previous studies investigating osmotic and/or salt responses have largely focused on understanding short-term responses (0-1h) at the transcriptomic, proteomic and phosphoproteomic level; however, our understanding of intermediate to longer-term adaptation (24h - days) is relatively limited. In addition to protein abundance and phosphorylation changes, recent evidence suggests reversible protein acetylation may be important for abiotic stress responses. Therefore, to characterize the effects of osmotic and salt stress, we undertook a label-free proteomic and PTMomic analysis of Arabidopsis roots exposed to 300mM Mannitol and 150mM NaCl for 24 h. We quantitatively assessed protein abundance, phosphorylation and acetylation.
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. Plants were grown on nylon meshes overlaying control 0.5MS media. At 9 DAS when third leaf is fully proliferating seedlings were transfered to either mannitol (25mM) or control plates, and proliferating leaves were micro-dissected at 1.5h, 3h, 12h and 24h after stress imposition and using RNAlater solution (25mM). Samples were from three independent biological experiments. Each sample was pooled from multiple plants and multiple plates in one experiment. RNA samples were submitted to ATH1 array hybridization.
Project description:Magnesium (Mg) is essential for many biological processes in plant cells and its deficiency causes yield reduction in crop systems. Low Mg status reportedly impacts on photosynthesis, sucrose partitioning and biomass allocation. However, earlier responses to Mg deficiency are scarcely described. Generally, symptoms of nutrient deficiency appear in specific ages of leaves. Therefore, we hypothesised that transcriptional responses to Mg deficiency are different depending on the ages of leaves, and performed a global transcriptomic analysis in two types of leaves; source and sink leaves of the model plant species Arabidopsis thaliana to reveal the earlier responses to Mg deficiency. The global transcriptomic study revealed that short-term Mg deficiency triggers the expression of defence response genes in sink leaves. In roots, although short-term Mg deficiency enhanced the Mg2+ uptake from the environmnet, transcriptional levels of genes encoding putative Mg2+ transporters in roots were unchanged, suggesting non-transcriptional regulation of Mg2+ uptake in roots.
Project description:Typically, when fully developed leaves of Arabidopsis thaliana are exposed to an increase in light intensity, they are able to increase their photosynthetic capacity in a process known as dynamic acclimation. Fully developed leaves of Arabidopsis thaliana were exposed to a fourfold increase in light intensity for 7 days to induce high light acclimation. This treatment was subjected to wild-type and a non-acclimating mutant lacking the gpt2 gene. The proteomic responses of the leaves were investigated using label-free mass spectrometry. A large reorganisation of the proteome was shown, with increases in the abundance of proteins of photosynthesis and carbon metabolism. Subtle differences were seen between the WT and gpt2 mutant: in the mutant, an increased stress response was seen, and some differences in the responses of metabolism. Proteomic responses generally correlated with physiological responses.
Project description:Typically, when fully developed leaves of Arabidopsis thaliana are exposed to an increase in light intensity, they are able to increase their photosynthetic capacity in a process known as dynamic acclimation. Fully developed leaves of Arabidopsis thaliana were exposed to a fourfold increase in light intensity for 7 days to induce high light acclimation. This treatment was subjected to wild-type and a non-acclimating mutant lacking the gpt2 gene. The proteomic responses of the leaves were investigated using label-free mass spectrometry. A large reorganisation of the proteome was shown, with increases in the abundance of proteins of photosynthesis and carbon metabolism. Subtle differences were seen between the WT and gpt2 mutant: in the mutant, an increased stress response was seen, and some differences in the responses of metabolism. Proteomic responses generally correlated with physiological responses.