Project description:Nitrogen (N) and phosphorus (P) are pivotal element for proper plant growth and development. We performed microarray analysis of rice shoot and root after nitrogen deficiency (-N) treatment under phosphorus deficiency (-P) condition to obtain a global view of gene regulations associated with plant response to -N under -P condition.
Project description:Purpose: To compare RNASeq data of Frankia strains (EAN1pec, EuIC and EUN1f) under nitrogen stress. Frankia cultures were grown for 2 days under nitrogen replete (+NH4) or nitrogen- deficient (N2) conditions. RNA-seq analysis provided insight into how the the bacteria responds to nitrogen stress.
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:The metabolic response of maize source leaves to low nitrogen supply was analyzed in maize seedlings by parallel measurements of transcriptome and metabolome profiling. Inbred lines A188 and B73 were cultivated under controlled growth chamber conditions and supplied with either sufficient (15mM) or limiting (0.15mM) nitrate supply. Leaf lamina material was harvested at day 20 and day 30 after germination with the fifth and sixth leaf representing the main source leaf respectively. Four replicates were collecetd from individual plants for each combination of genotype, growth stage and nitrogen treatment. The leaf material was frozen, homogenised and aliquoted for transcriptome and metabolome analysis. The molecular data was further supplemented by phenotypic characterisation of the maize seedlings under investigation. Limited availability of nitrogen caused strong shifts in the metabolite profile of leaves. The transcriptome was less affected by the nitrogen stress but showed strong genotype and age dependent patterns. Nitrogen starvation initiated the selective down-regulation of processes involved in nitrate reduction and amino acid assimilation; ammonium assimilation related transcripts on the other hand were not influenced. Carbon assimilation related transcripts were characterized by high transcriptional coordination and general down-regulation under low nitrogen conditions. Nitrogen deprivation caused a slight accumulation of starch, but also directed increased amounts of carbohydrates into the cell wall and secondary metabolites. The decrease in N availability also resulted in accumulation of phosphate and by strong down-regulation of genes usually involved in phosphate starvation response, underlining the great importance of phosphate homeostasis control under stress conditions.
Project description:We study the effect of nitrogen limitation on the growth and development of poplar roots. We used microarrays to detail the global program of gene expression underlying morphological and developmental changes driven by low nitrogen in the growth media. We report the effect of nitrogen limitation on the growth and development of poplar roots. Low nitrogen concentration led to increased root elongation followed by lateral root proliferation and finally increased root biomass. These morphological responses correlated with high and specific activation of genes encoding regulators of cell cycle and enzymes involved in cell wall biogenesis, growth and remodeling. Comparative analysis of poplar and Arabidopsis root transcriptomes under nitrogen deficiency indicated many similarities and diversification in the response in the two species. A reconstruction of genetic regulatory network (GRN) analysis revealed a sub-network centered on a PtaNAC1-like transcription factor. Consistent with the GRN predictions, root-specific upregulation of PtaNAC1 in transgenic poplar plants increased root biomass and led to significant changes in the expression of the connected genes specifically under low nitrogen. PtaNAC1 and its regulatory miR164 showed inverse expression profiles during response to LN, suggesting of a micro RNA mediated attenuation of PtaNAC1 transcript abundance in response to nitrogen deprivation.
Project description:Transcriptome sequencing (RNA-seq) was used to sequence the leaves of Xanthoceras sorbifolia Bunge under low nitrogen, so as to analyze the resistance of Xanthoceras sorbifolia Bunge to low nitrogen.
Project description:The purpose of this study was to evaluate a set of 6-7 long oligonucleotide probes developed based on the sequence of the Populus trichocarpa genome, that are optimal for gene expression analysis of P. deltoides and a hybrid of P. deltoides and P. trichocarpa. To evaluate these probes, multiple tissues (differentiating xyle, leaf and whole-root) of a pure P. deltoides and a hybrid (P. deltoides X P. trichocarpa) were transcript profiled for identification of one or more probes that are not biased towards one or the other genotype.