Project description:To optimize access to nitrogen under limiting conditions, root systems must continuously sense and respond to local or temporal fluctuations in nitrogen availability. In Arabidopsis thaliana and several other species, external N levels that induce only mild deficiency stimulate the emergence of lateral roots and especially the elongation of primary and lateral roots. However, the identity of the genes involved in this coordination remains still largely elusive. In order to identify novel genes and mechanisms underlying nitrogen-dependent root morphological changes, we investigated time-dependent changes in the root transcriptome of Arabidopsis thaliana plants grown under sufficient nitrogen or under conditions that induced mild nitrogen deficiency.
Project description:To gain further insights into a larger number of processes potentially altered by high nickel (Ni), we performed a transcriptional profiling of whole roots of Arabidopsis thaliana accession Columbia-0 (Col-0) exposed to 100 µM nickel, a concentration that induces slight chlorosis and intermediate inhibition of root and shoot growth.
Project description:Phosphate (Pi) deficiency alters root hair length and frequency as a means of increasing the absorptive surface area of roots. Three partly redundant single R3 MYB proteins, CAPRICE (CPC), ENHANCER OF TRY AND CPC1 (ETC1) and TRIPTYCHON (TRY), positively regulate the root hair cell fate by participating in a lateral inhibition mechanism. To identify putative targets and processes that are controlled by these three transcription factors (TFs), we conducted transcriptional profiling of roots from Arabidopsis thaliana wild-type plants, and cpc, etc1 and try mutants grown under Pi-replete and Pi-deficient conditions using RNA-seq.
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:Arabidopsis thaliana plants were grown from seeds in Petri dishes on MS medium. 4 days old plants were co-incubated with L. bicolor without physical contact. After 2 days of co-incubation, roots were either harvested whole or separated into the root tip (ca. 1/4 of the whole root) and the lateral root zone (= remaining root).
