Project description:Plants aquire nitrogen from the soil, most commonly in the form of either nitrate or ammonium. Unlike ammonium, nitrate must be reduced (with NADH and ferredoxin as electron donors) prior to assimilation. Thus, nitrate nutrition imposes a substantially greater energetic cost than ammonium nutrition. Our goal was to compare the transcriptomes of nitrate-supplied and ammonium-supplied plants, with a particular interest in characterizing the differences in redox metabolism elicited by different forms of inorganic nitrogen. We used microarrays to compare the short-term transcriptional response to either nitrogen supply or ammonium supply in Arabidopsis roots. Genes upregulated or downregulated by nitrate only, ammonium only, or both ammonium and nitrate were identified and analyzed. Arabidopsis thaliana (Col-0) plants were grown hydroponically until they reached growth stage 5.10. They were then transferred to a nitrogen-free medium for 26 hr and then supplied with 1 mM nitrate or 1 mM ammonium. RNA isolation (and subsequent microarray analysis) was performed on root tissue isolated just before nitrogen supply (time 0) and at 1.5 hr and 8 hr after nitrogen supply (1.5 hr nitrate, 8 hr nitrate, 1.5 hr ammonium, 8 hr ammonium).
Project description:This experiment was set up in order to identify the (direct) transcriptional targets of the Ethylene Response Factor 115 (ERF115) transcription factor. Because ERF115 expression occurs in quiescent center (QC) cells and strong effects on the QC cells were observed in ERF115 overexpression plants, root tips were harvested for transcript profiling in order to focus on root meristem and QC specific transcriptional targets. Wild-type (Col-0 ecotype), erf115 mutant (SALK_021981) and ERF115 overexpressing (p35S:ERF115 ORF) root tips (three replicates each) were harvested and subjected to transcript profiling, using the Col-0 samples as control reference.
Project description:To gain insight into the molecular mechanisms underlying the increased growth of Col-0:MtNPF1.7 CE plants compared to WT, leaves from plants grown for 21 days on defined media were subjected to transcript profiling using the Affymetrix Arabidopsis ATH1 microarray. We tested gene expression from plants grown at 0.1 mM nitrate and at 10 mM nitrate. The 0.1 mM nitrate concentration is below MtNPF1.7’s Km and at that nitrate concentration, large growth differences between Col-0:MtNPF1.7 CE and wild-type Col-0 plants were observed, while 10 mM nitrate is well above MtNPF1.7’s Km, where fewer differences in growth were seen. Three independent biological replicates were collected.
Project description:Transcriptional profiling of an Fd-GOGAT1/GLU1 mutant in Arabidopsis thaliana reveals a multiple stress response and extensive reprogramming of the transcriptome Glutamate plays a central position in the synthesis of a variety of organic molecules in plants and is synthesised from nitrate through a series of enzymatic reactions. Glutamate synthases catalyse the last step in this pathway and two types are present in plants: NADH- or ferredoxin-dependent. Here we report a genome wide microarray analysis of the transcriptional reprogramming that occurs in leaves and roots of the A. thaliana mutant glu1-2 knocked-down in the expression of Fd-GOGAT1 (GLU1; At5g04140), one of the two genes of A. thaliana encoding ferredoxin-dependent glutamate synthase. Rosette leaves and roots from the glu1-2 mutant, which is a T-DNA knockout of a ferredoxin dependent glutamate synthase in Arabidopsis (locus ID: At5g04140), were analyzed on Affymetrix microarrays. As a reference control, leaves and roots from Col(0) plants were used. The glu1-2 mutant is derived from a Col(0) accession. Four independent biological replicas from leaves and roots were used in the analysis (from both glu1-2 and Col(0) reference). In total 16 hybridizations were done.
Project description:The RETINOBLASTOMA–RELATED (RBR) is a key regulator of cell proliferation and differentiation in plants, and plays an important role in maintenance of the stem cell niche in the root. We used microarray analysis to characterize the transcriptional response of Arabidopsis thaliana root tips from rRBr mutant (7 samples) against Col-0 wild type (6 samples) after 4, 6 and 10 das.
Project description:Transcriptional profiling of Arabidopsis thaliana 12-days old seedlings comparing Col-0 wild type with transgenic plants with altered expression of dual-targetting plastid/mitochondrial organellar RNA-polymerase RPOTmp. Transgenic plants used for experiment were: overexpressor plants obtained by transformation of Col-0 WT plants with genetic constructs created in [Tarasenko et al., 2016] contained catalytic part of RPOTmp enzyme with transit peptides of RPOTm (mitochondrial) and RPOTp (plastid) by agrobacterial transformation; plants with complementation of RPOTmp functions in mitochondria or chloroplasts obtained from transformation of GABI_286E07 rpotmp knockout-mutant plants with genetic constructs created in [Tarasenko et al., 2016]. Goal was to determine the effects of RPOTmp knockout/overexpression on global Arabidopsis thaliana gene expression.
Project description:Expression analysis was performed with two TDNA insertion mutants of taf4b i.e; taf4bprm (TDNA insertion in promoter region) and taf4bint (TDNA insertion in intronic region), Taf4b overexpression lines, taf4bprmcpr5 double mutant lines (Double mutant was generated by crossing taf4bprm with cpr5) and Col-0 in normal condition as well as with taf4bprm mutant and Col-0 infected with fungi AB (Alternaria brassicicola) and bacteria ES4 (Pseudomonas syringae pv.maculicola ES4326 ) in different perspectives. Affymatrix expression analysis was executed to provide mechanistic details of regulation of genes by Taf4b in plants.
Project description:This study evaluated the transcriptomic profiles of Arabidopsis thaliana (Col-0) plants grown along bacterial isolates whose interactions induce root morhology changes in the plant
Project description:Arabidopsis Affymetrix ATH1 GeneChips were used to compare the mRNA profiles of root tissues of the grf1/grf2/grf3 triple mutant and transgenic plants overexpressing miR396-resistant variants of GRF1 (P35S:rGRF1) or GRF3 (P35S:rGRF3) with those of the corresponding wild-type (Col-0 or WS). Wild-type (Arabidopsis thaliana ecotypes Col-0 and Ws), the triple mutant grf1/grf2/grf3, and transgenic plants overexpressing rGRF1 or rGRF3 were grown in vertical culture dishes on modified Knop’s medium for 2 weeks and then root tissues were collected for RNA extraction. ****[PLEXdb(http://www.plexdb.org) has submitted this series at GEO on behalf of the original contributor, Tarek Hewezi. The equivalent experiment is AT109 at PLEXdb.]