Project description:Fourteen days plants growth under hydroponic +P condition (200 μM) were treated under –P (no phosphate) condition for another 7 days, shoot of plants from 3 biological repeats were sampled for Affymetrix microarray analysis. We used microarrays to detail the global programme of gene expression underlying -Pi condition among WT and mutants of phr1, phr3 and triple mutant of phr1phr2phr3.
Project description:We performed a transcriptomic analysis of Pi starvation responses in Arabidopsis thaliana (Columbia-0) phr1 mutant plants expressing PHR1 in presence of cicloheximide, that inhibit protein translation, thus preventing any effect of PHR1 on the expression of indirect targets. Results show the primary target genes of PHR1 in the responses to Pi starvation.
Project description:We performed a transcriptomic analysis of Pi starvation responses in Arabidopsis thaliana (Columbia-0) phr1 mutant plants expressing PHR1 in presence of cicloheximide, that inhibit protein translation, thus preventing any effect of PHR1 on the expression of indirect targets. Results show the primary target genes of PHR1 in the responses to Pi starvation. The analysis was performed in phr1 plants and phr1 plants overexpressing a fusion GR:PHR1 (OXGR:PHR1) whose activity is postranslationally controlled by dexamethasone (DEX), that allows studying gene expression upon PHR1 activation and the concomitant inhibition of translation with cycloheximide (CHX), thus preventing any effect of PHR1 on the expression of indirect targets. To perform this study, phr1 and OXGR:PHR1 phr1 plants were grown for seven days in complete Johnson liquid media (+Pi), 2 days in Pi-lacking media (-Pi) and then supplemented with 5 µM DEX and 10 µM CHX for 6 hours before harvesting. Three independent biological samples of total RNA from shoot and root were hybridized separately.
Project description:Fourteen days plants growth under hydroponic +P condition (200 μM) were treated under –P (no phosphate) condition for another 7 days, shoot of plants from 3 biological repeats were sampled for Affymetrix microarray analysis. We used microarrays to detail the global programme of gene expression underlying -Pi condition among WT and mutants of phr1, phr3 and triple mutant of phr1phr2phr3. Fourteen days plants growth under hydroponic +P condition (200 μM) were treated under –P (no phosphate) condition for another 7 days, shoot of plants from 3 biological repeats were sampled for Affymetrix microarray analysis.
Project description:To better understand the complex mechanisms regulating Pi homeostasis in rice (Oryza sativa L. cv. Nipponbare), a time course experiment was performed, where pre-germinated seedlings were grown hydroponically for two weeks on Pi-sufficient medium (0.32 mM Pi), before transferring half of the plants to Pi-deficient solution (0 mM Pi) for 21 days (d). After three weeks of Pi-starvation treatment, half of these plants where then re-supplied with Pi sufficient media for up to 24 hours (h). In total, nine time points were selected in order to cover short and long term responses to Pi starvation as well as the effects of Pi re-supply on Pi starved plants.
Project description:A comprehensive time-course experiment of Pi-starved plants was undertaken, spanning medium (3 and 7 days), and long-term (21 days up to 52 days) Pi deprivation (âPi), as well as both short term (1 and 3 days) and long-term (31 days) recovery. The 52 days time point consisting of 21 days starvation +31 days recovery enabled investigation of the effects of long term resupply on Pi starved plants, and coincided with the emergence of the first panicles and grains. Pre-germinated rice seedlings were grown for 14 days in Pi sufficient conditions (0.32 mM Pi) before being transferred to either Pi sufficient (0.32 mM Pi) or Pi deficient (0 mM Pi) media for 21 days. After 21 days of Pi deficient treatment, half of the plants were either maintained under Pi deficient conditions or re-supplied with Pi (0.32 mM) for 1, 3 or 31 days. To confirm the effectiveness of the Pi starvation and resupply treatments, physiological and molecular analyses were performed.
Project description:Phosphate starvation/sufficient rice seedling, root or shoot Pi-starvation or Pi-sufficient stresses responsible rice genes, including previously unannotated genes were identified by Illumina mRNA-seq technology. 53 million reads from Pi-starvation or Pi-sufficient root or shoot tissues were uniquely mapped to the rice genome, and these included 40574 RAP3 transcripts in root and 39748 RAP3 transcripts in shoot. We compared our mRNA-seq expression data with that from Rice 44K oligomicroarray, and about 95.5% (root) and 95.4% (shoot) transcripts supported by the array were confirmed expression both by the array and by mRNA-seq, Moreover, 11888 (root) and 11098 (shoot) RAP genes which were not supported by array, were evidenced expression with mRNA-seq. Furthermore, we discovered 8590 (root) and 8193 (shoot) previously unannotated transcripts upon Pi-starvation and/or Pi-sufficient.
Project description:We performed a transcriptomic analysis of Pi-starvation and recovery after resupplying Pi in Arabidopsis thaliana (Columbia-0) wild type plants and double mutant spx1,spx2. Results show that SPX1 is a Pi-dependent inhibitor of the transcription factor PHR1, a central regulatory protein in the control of transcriptional responses to Pi starvation.
Project description:We performed a transcriptomic analysis of Pi starvation responses in Arabidopsis thaliana (Columbia-0) wild type plants under phosphate starvation stress and in plants with altered PHR1(-like) activity, comparing mutants of phr1 and phr1-phl1 grown in phosphate-lacking medium. Results show the central role of PHR1 and functionally redundant members of its family in the control of transcriptional responses to Pi starvation. The analysis was performed in wild-type plants grown for seven days in complete (+Pi) and Pi-lacking (-Pi) Johnson solid media and the single phr1 and double phr1-phl1 mutants grown for 7 days in –Pi medium. Three independent biological samples of total RNA from shoot and root were hybridized separately.