Phosphorus starvation induced genes in Brassica carinata
ABSTRACT: The purpose of the present study is to determine the effect of Phosphorus deficiency on gene expression level using microarray analysis to identify genes responsible for root hair development. Phosphorus deficiency induced the formation of root hairs to explore a greater soil volume but molecular mechanisms were unknown. Therefore, microarray experiments were performed using root tips of Brassica carinata cultivars Bale and Bacho, respectively differing in root hair length during Phosphorus deficiency. Experimental design was carried out in nutrient solution in a climate chamber with controlled environmental conditions (20°C, 16h day/8h night cycle, 70% relative humidity) in a randomized design. 25 root tips from 10 day old seedlings grown without Phosphorus of 1cm length were harvested and immediately frozen in liquid nitrogen. Gene expression analyses were performed Results from xy microarrays are summarized in this study. The samples originate from roots of cultivars Bale and Bacho grown in Phosphorus deficient conditions. Microarrays were hybridized with Cy3 and Cy5 labeled cDNA from Bale and Bacho both during Phosphorus deficiency using a dye swap approach
Project description:The purpose of the present study is to determine the effect of Phosphorus deficiency on gene expression level using microarray analysis to identify genes responsible for root hair development. Phosphorus deficiency induced the formation of root hairs to explore a greater soil volume but molecular mechanisms were unknown. Therefore, microarray experiments were performed using root tips of Brassica carinata cultivars Bale and Bacho, respectively differing in root hair length during Phosphorus deficiency. Experimental design was carried out in nutrient solution in a climate chamber with controlled environmental conditions (20°C, 16h day/8h night cycle, 70% relative humidity) in a randomized design. 25 root tips from 10 day old seedlings grown without Phosphorus of 1cm length were harvested and immediately frozen in liquid nitrogen. Gene expression analyses were performed Overall design: Results from xy microarrays are summarized in this study. The samples originate from roots of cultivars Bale and Bacho grown in Phosphorus deficient conditions. Microarrays were hybridized with Cy3 and Cy5 labeled cDNA from Bale and Bacho both during Phosphorus deficiency using a dye swap approach
Project description:The objective of this project is to identify genes that are expressed in the Arabidopsis thaliana root tip and that are early induced (or repressed) by phoshate deficiency. Seedlings were germinated and grown (for 6 days) on phosphate rich medium and transfered to either a phosphate poor medium (Pi- = 20uM Pi treatment) or a phosphate rich medium (Pi+ = 500uM, Pi = control). Fifteen and 60 minutes after transfer, the tip (~800um) of the primary root was cut under a dissecting microscope. About 100 root tips per condition were harvested and there mRNA was analysed with the use of microarrays. 6 dye-swap - time course,treated vs untreated comparison
Project description:Phosphate (Pi) deficiency severely affects crop yield. Modern high yielding rice genotypes are sensitive to Pi deficiency whereas traditional rice cultivars are naturally compatible to low Pi ecosystems. However, the underlying molecular mechanisms for low Pi tolerance in traditional genotypes remain largely elusive. To delineate the molecular mechanisms for low Pi tolerance, two contrasting rice genotypes - Dular (low Pi tolerant) and PB1 (low Pi sensitive) - have been selected. Comparative morphophysiological, global transcriptome and lipidome analyses of root and shoot tissues of both genotypes raised under Pi deficient and sufficient conditions revealed the potential low Pi tolerance mechanisms of traditional genotype. Most of the genes associated with enhanced internal Pi utilization (phospholipid remobilization) and modulation of root system architecture (RSA) are highly induced in traditional rice genotype, Dular. Higher reserve of phospholipid and greater accumulation of galactolipids under low Pi in Dular indicated its better internal Pi utilization. Furthermore, Dular also maintained better root growth than PB1 under low Pi resulting in larger root surface area due to increased lateral root density and root hair length. Genes involved in enhanced low Pi tolerance of traditional genotype can be exploited to improve the low Pi tolerance of modern high yielding rice cultivars. Overall design: 15-days-old Root and shoot tissue of rice seedlings (variety: Dular and PB1) grown under Phosphorus deficient conditions were compared with corresponding Phosphorus sufficient conditions
Project description:Phosphorus, in its orthophosphate form (Pi), is one of the most limiting macronutrients in soils for plant growth and development. However, the whole genome molecular mechanisms contributing to plant acclimation to Pi deficiency remain largely unknown. White lupin (Lupinus albus L.) has evolved unique adaptations for growth in Pi deficient soils including the development of cluster roots to increase root surface area. In this study, we utilized RNA-Seq technology to assess global gene expression in white lupin cluster roots, normal roots, and leaves in response to Pi supply. We de novo assembled 277,224,180 Illumina reads from 12 cDNA libraries to build the first white lupin gene index (LAGI 1.0). This index contains 125,821 unique sequences with an average length of 1,155 bp. Of these sequences 50,734 were transcriptionally active (RPKM = 3) representing approximately 7.8% of the Lupinus albus genome, using the predicted genome size of Lupinus angustifolius as a reference. We identified a total of 2,128 sequences differentially expressed in response to Pi deficiency with a = 2-fold change and a p-value = 0.05. Twelve sequences were consistently differentially expressed due to Pi deficiency stress in three species, making them ideal candidates to monitor the Pi status of plants. Additionally, classic physiological experiments were coupled with RNA-Seq data to examine the role of cytokinin and gibberellic acid in Pi deficiency-induced cluster root development. This global gene expression analysis provides new insights into the biochemical and molecular mechanisms involved in the acclimation to Pi deficiency. Examination of 2 different tissue types (roots and leaves) under phosphorus (P) -sufficient or P-deficient condition with 3 biological replications per condition in white lupin (Lupinus albus).
Project description:Masson pine (Pinus massoniana) has evolved some adaptations for growth in low P soils. To elucidate these mechanisms, we investigated global gene expression profiles of the masson pine responding to long-term phosphorus starvation and different Pi levels (P1, 0.01 mM P; P2, 0.06 mM P). Analysis used phosphorus-sufficient treatment RNA as control samples for comparison to the experimental samples (P1 and P2) taken at 12, 24, 48 and 60 day. Indirect comparisons were made across multiple arrays with raw data pulled from different channels for data analysis and comparison to the control data.
Project description:Deep sequencing of Arabidopsis thaliana small RNAs was conducted to reveal microRNAs (miRNAs) and other small RNAs that were differentially expressed in response to phosphate (Pi) deficiency. About 3.5 million sequence reads corresponding to 0.6-1.2 million unique sequence tags from each Pi-sufficient or -deficient root or shoot sample were mapped to the Arabidopsis genome. We showed that upon Pi deprivation, the expression of miR156, miR399, miR778 and miR827 was induced, whereas the expression of miR169, miR395 and miR398 was repressed. We found crosstalks coordinated by these miRNAs under different nutrient deficiencies. Moreover, we found a new miRNA family upregulated specifically by Pi deficiency. In addition to miRNAs, we identified one Pi starvation-induced DCL1-dependent small RNA derived from the long terminal repeat of a retrotransposon and a group of 19-nucleotide small RNAs corresponding to the 5' end of tRNA and expressed at a high level in Pi-starved roots. Interestingly, we observed an increased abundance of TAS4-derived trans-acting siRNAs (ta-siRNAs) in Pi-deficient shoots and uncovered an autoregulatory mechanism of PAP1/MYB75 via miR828 and TAS4-siR81(-) that regulates the biosynthesis of anthocyanin. This finding sheds light on the regulatory network between miRNA/ta-siRNA and its target gene. Of note, a substantial amount of miR399* accumulated under Pi deficiency. Like miR399, miR399* can move across the graft junction, implying a potential biological role for miR399*. This study represents a comprehensive expression profiling of Pi-responsive small RNAs and advances our understanding of the regulation of Pi homeostasis mediated by small RNAs. Keywords: Transcriptome analysis Examination of 4 samples from root and shoot tissues of Arabidopsis in either phosphate-sufficient or phosphate-deficient condition
Project description:The Chlamydomonas reinhardtii transcription factor PSR1 is required for the control of activities involved in scavenging phosphate from the environment during periods of phosphorus limitation. Increased scavenging activity reflects the development of high-affinity phosphate transport and the expression of extracellular phosphatases that can cleave phosphate from organic compounds in the environment. A comparison of gene expression patterns using microarray analyses and quantitative PCRs with wild-type and psr1 mutant cells deprived of phosphorus has revealed that PSR1 also controls genes encoding proteins with potential "electron valve" functions--these proteins can serve as alternative electron acceptors that help prevent photodamage caused by overexcitation of the photosynthetic electron transport system. In accordance with this finding, phosphorus-starved psr1 mutants die when subjected to elevated light intensities; at these intensities, the wild-type cells still exhibit rapid growth. Acclimation to phosphorus deprivation also involves a reduction in the levels of transcripts encoding proteins involved in photosynthesis and both cytoplasmic and chloroplast translation as well as an increase in the levels of transcripts encoding stress-associated chaperones and proteases. Surprisingly, phosphorus-deficient psr1 cells (but not wild-type cells) also display expression patterns associated with specific responses to sulfur deprivation, suggesting a hitherto unsuspected link between the signal transduction pathways involved in controlling phosphorus and sulfur starvation responses. Together, these results demonstrate that PSR1 is critical for the survival of cells under conditions of suboptimal phosphorus availability and that it plays a key role in controlling both scavenging responses and the ability of the cell to manage excess absorbed excitation energy. Set of arrays that are part of repeated experiments Biological Replicate Computed
Project description:Nipponbare performs poorly in phosphorus (P) deficient soil whereas a Nipponbare-derived NIL containing the Pup1 allele of donor parent Kasalath is tolerant to P deficiency. In this experiment we compared gene expression patterns in roots of this NIL to Nipponbare, grown either in a P deficient or P fertilized soil. The aim is to separate constitutive differences in expression from those induced by P deficiency. Experiment Overall Design: Total RNA was extrancted from root that were grown under two conditions and prepared three biological replicant in each line (total 6 samples in each line). Experiment Overall Design: We used 6 slides for this experiment, in each slide, Nipponbare and 6-4 samples grown under same condition were hybridized.
Project description:What are the gene expressed during meiosis pathway in Arabidopsis thalina. Comparison of total RNAs from isolated meiocytes with those isolated from root tips, and those from leaves. Comparison of transcriptomes of normal stamen (ecotype columbia) with root tips and leaves. And, comparison of transcriptomes of normal stamens (ecotype L. erecta) with stamens from sporocyteless mutant (L. erecta). Keywords: organ comparison 11 dye-swap - CATMA arrays
Project description:OsPSTOL1 confers phosphorus (P)-deficiency tolerance in rice through enhancement of early root growth. The larger root surface area at early stage provides the plants an advantage for nutrient uptake. We conducted microarrays to determine the genes which are constitutively regulated by OsPSTOL1, independent of P supply and developmental stage. For Affymetrix microarrays, root RNA samples from IR64 35S::OsPSTOL1 plants (transgenic: T) and Nulls (non-transgenic: NT) grown in P-deficient soil +/- application of P fertilizer were used. Plants were at the reproductive/heading stage (- P treatment) and at mid-tillering (+P treatment), respectively.