Transcript profiling of transgenic Arabidopsis thaliana seedlings constitutively overexpressing UGT74E2 (35S::UGT74E2).
Perturbation of indole-3-butyric acid homeostasis by the UDP-glucosyltransferase UGT74E2 modulates Arabidopsis architecture and water stress tolerance.
Specimen part
View SamplesIn response to WRKY40 and WRKY60 perturbation (and high light stress), significant transcriptional re-programming occurs particularly for genes encoding stress responsive mitochondrial and choloplast proteins.
AtWRKY40 and AtWRKY63 modulate the expression of stress-responsive nuclear genes encoding mitochondrial and chloroplast proteins.
Specimen part, Treatment
View SamplesDrought 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.
Developmental stage specificity and the role of mitochondrial metabolism in the response of Arabidopsis leaves to prolonged mild osmotic stress.
Specimen part
View SamplesMitochondrial stress stimuli such as AA caused a transient suppression of auxin signaling and conversely, auxin treatment represses a part of the response to AA treatment.
A Functional Antagonistic Relationship between Auxin and Mitochondrial Retrograde Signaling Regulates Alternative Oxidase1a Expression in Arabidopsis.
Treatment
View SamplesStresses that target mitochondrial function lead to altered transcriptional responses for 100-1000s of genes genome wide, and are signalled via retrograde communication pathways within the cell. rao2 mutants contain a mutation in the NAC family transcription factor ANAC017 and cannot induce stress responsive genes (such as the mitochondrial alternative oxidase 1a) in response to mitochondrial dysfunction. We sought to define the global gene network regulated through RAO2 function in response to mitochondrial stress (mimicked through treatment of plants with antimycin A - a specific inhibitor of complex III in the mitochondrial electron transfer chain), and non-specific stress signals such as hydrogen peroxide. We have defined global stress responses that are positively and negatively mediated by RAO2 function, and show that greater than 80% of transcripts that are differentially regulated under H2O2 stress require proper functioning of ANAC017 for a normal stress responses.
A membrane-bound NAC transcription factor, ANAC017, mediates mitochondrial retrograde signaling in Arabidopsis.
Treatment
View SamplesThe translocase of the inner membrane 17-1 (Tim17-1) plays a defined role in germination in Arabidopsis thaliana
The mitochondrial protein import component, TRANSLOCASE OF THE INNER MEMBRANE17-1, plays a role in defining the timing of germination in Arabidopsis.
Specimen part, Time
View SamplesArabidopsis ATH1 Genome Arrays were used to analyse changes in transcript abundance between Col-0 (wild-type) Arabidopsis seedlings and either single T-DNA insertional KO mutants of LETM1 (At3g59820)(T-DNA lines; SALK_067558C (letm1-1) and SALK_058471 (letm1-2)) or LETM2 (At1g65540) (T-DNA line; SALK_068877 (letm2-1)). Additionally, letm1 and letm2 knock out Arabidopsis lines were crossed to generate double mutants, however a double knock-out of these two genes results in an embryo lethal phenotype. Hemizygous plants were generated that were homozygous knock out for LETM1 and heterozygous knock out for LETM2, and visa versa, termed (letm1(-/-)LETM2(+/-) and (LETM1(+/-)letm2(-/-) respectively. Note that (letm1(-/-)LETM2(+/-) displays a mild developmental defective phenotype in the first 10-14 days of growth, while (LETM1(+/-)letm2(-/-) shows no phenotype. Microarray analysis was carried out on all three single homozygous knock out lines, and also on both combinations of the hemizygous mutation between the two genes, and compared with a wild-type Col-0 control to gain insight into global transcript abundance changes in these mutant lines. Arrays were performed in triplicate for each genotype, from RNA isolated from 3 independent pools of 5-10 Arabidopsis seedlings at 10 days old.
LETM proteins play a role in the accumulation of mitochondrially encoded proteins in Arabidopsis thaliana and AtLETM2 displays parent of origin effects.
Age, Specimen part
View SamplesThe energetic (ATP) cost of biochemical pathways critically determines the maximum yield of metabolites of vital or commercial relevance. Cytosolic acetyl-CoA is a key precursor for biosynthesis in eukaryotes and for many industrially relevant product pathways that have been introduced into Saccharomyces cerevisiae, such as isoprenoids or lipids. In this yeast, synthesis of cytosolic acetyl-CoA via acetyl-CoA synthetase (ACS) involves hydrolysis of ATP to AMP and pyrophosphate. Here, we demonstrate that expression and assembly in the yeast cytosol of a pyruvate dehydrogenase complex (PDH) from Enterococcus faecalis can fully replace the ACS-dependent pathway for cytosolic acetyl-CoA synthesis. In vivo activity of E. faecalis PDH required the simultaneous expression of E. faecalis genes encoding its E1a, E1ß, E2 and E3 subunits, as well as genes involved in lipoylation of E2 and addition of lipoate to growth media. A strain lacking ACS, that expressed these E. faecalis genes, grew at near-wild-type rates on glucose synthetic medium supplemented with lipoate, under aerobic and anaerobic conditions. A physiological comparison of the engineered strain and an isogenic Acs+ reference strain showed small differences in biomass yields and metabolic fluxes. Cellular fractionation and gel filtration studies revealed that the E. faecalis PDH subunits were assembled in the yeast cytosol, with a subunit ratio and enzyme activity similar to values reported for PDH purified from E. faecalis. This study indicates that cytosolic expression and assembly of PDH in eukaryotic industrial micro-organisms is a promising option for minimizing the energy costs of precursor supply in acetyl-CoA-dependent product pathways. Overall design: For both strains - mutant strain IMY104 and reference strain CEN.PK113-7D'' three independent chemostat cultures were performed. Each of the chemosta was sampled for transcriptome analysis. Samples were processed as described below.
Engineering acetyl coenzyme A supply: functional expression of a bacterial pyruvate dehydrogenase complex in the cytosol of Saccharomyces cerevisiae.
Cell line, Subject
View SamplesTotal RNA microarray data from Fresh-Frozen Glioblastoma tumor samples.
Epigenetic suppression of EGFR signaling in G-CIMP+ glioblastomas.
Specimen part, Disease stage
View SamplesMuscle biopsy samples were obtained from two groups of male subjects prior to endurance training. The samples were used to predict training responses.
Using molecular classification to predict gains in maximal aerobic capacity following endurance exercise training in humans.
Sex
View Samples