Project description:Sugar is an important resource for energy generation and developmental regulation in plants, and sucrose starvation causes enormous changes in cellular morphology, enzyme activities and gene expression. Genome-wide gene expression profiling provides a comprehensive knowledge into gene expression under nutrients depletion and senescence, however, that of monocot model plant rice under sucrose depletion is still under investigation. Here, the time-course monitoring of gene expression profiles in sucrose-starved rice (Oryza sativa cv Tainung67) suspension cells was investigated by 21495 probes-containing Agilent rice chip. In sucrose-starved cells, the induced vacuolar biogenesis was coincided with the significantly upregulated expression of genes encoding H+-pyrophosphatase, delta-TIP, one putative alpha-TIP, several vacuolar proteases and proteinase inhibitors, and one OsATG3. To survey the overall metabolic adaptations under sucrose depletion the genes significantly alternating expression level were incorporated into multiple metabolic pathways. The majority of genes encoding enzymes involved in biosynthesis and degradation pathways of various macromolecules were comprehensively down- and upregulated, respectively, by sucrose starvation. Transcriptional regulation of gene expression is important for the physiological adaptations to environmental stress and many transcription factors, including bZIPs, NACs, and WRKY showed significant increase in transcript levels under sucrose starvation. Concurrently, statistical analysis reveals that their corresponding consensus cis-elements, such as ABA-responsive element, CACG, ACI, ACII and CTTATCC, are frequently found in the promoter regions of many Suc starvation-upregulated genes. Particle bombardment-mediated transient promoter activity assays further showed that the CTTATCC, derived form TATCCA, and the AC motifs, are the promising sucrose starvation responsive activators in sucrose-starved rice suspension cells. Keywords: stress response
Project description:Sugar is an important resource for energy generation and developmental regulation in plants, and sucrose starvation causes enormous changes in cellular morphology, enzyme activities and gene expression. Genome-wide gene expression profiling provides a comprehensive knowledge into gene expression under nutrients depletion and senescence, however, that of monocot model plant rice under sucrose depletion is still under investigation. Here, the time-course monitoring of gene expression profiles in sucrose-starved rice (Oryza sativa cv Tainung67) suspension cells was investigated by 21495 probes-containing Agilent rice chip. In sucrose-starved cells, the induced vacuolar biogenesis was coincided with the significantly upregulated expression of genes encoding H+-pyrophosphatase, ï?¤-TIP, one putative ï?¡-TIP, several vacuolar proteases and proteinase inhibitors, and one OsATG3. To survey the overall metabolic adaptations under sucrose depletion the genes significantly alternating expression level were incorporated into multiple metabolic pathways. The majority of genes encoding enzymes involved in biosynthesis and degradation pathways of various macromolecules were comprehensively down- and upregulated, respectively, by sucrose starvation. Transcriptional regulation of gene expression is important for the physiological adaptations to environmental stress and many transcription factors, including bZIPs, NACs, and WRKY showed significant increase in transcript levels under sucrose starvation. Concurrently, statistical analysis reveals that their corresponding consensus cis-elements, such as ABA-responsive element, CACG, ACI, ACII and CTTATCC, are frequently found in the promoter regions of many Suc starvation-upregulated genes. Particle bombardment-mediated transient promoter activity assays further showed that the CTTATCC, derived form TATCCA, and the AC motifs, are the promising sucrose starvation responsive activators in sucrose-starved rice suspension cells. Experiment Overall Design: We used Agilent rice gene chips to investigate the gene expression profiling in rice cells after periods of 12, 24 and 48 h Suc starvation. To eliminate the effect of osmotic stress on alternation of gene expression, an additional set of control, 88 mM Sorbitol in MS medium verse Suc-free samples for 12 h Suc starvation, was also applied for array analysis.
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:This experiment was designed to identify transcribed regions of japonica subspecies of the rice genome. A series of high-density oligonucleotide tiling arrays that represent sense and antisense strands of the entire nonrepetitive sequence of all the 12 chromosomes were designed to measure genome-wide transcription. A total of 12253842 36mer oligonucleotide probes positioned every 46 nt on average were used for this purpose. The probes were synthesized via maskless photolithography at a feature density of approximately 389,000 probes per slide. The arrays were hybridized with fluorescence-labeled cDNA reverse-transcribed from equal amounts of four selected poly(A)+ RNA population (seedling root, seedling shoot, panicle, and suspension cultured cells). Keywords: tiling array, genome-wide transcription
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:Nitrogen (N), a critical macronutrient for plant growth and development, is a major limiting factor in most agricultural systems. Microarray analyses have been conducted to investigate genome-wide gene expression in response to changes in N concentrations. Although RNA-Seq analysis can provide a more precise determination of transcript levels, it has not previously been employed to investigate the expression of N-starvation-induced genes. We constructed cDNA libraries from leaf sheaths and roots of rice plants grown under N-deficient or -sufficient conditions for 12 h. Sequencing the libraries resulted in identification of 33,782 annotated genes. A comparison of abundances revealed 1,650 transcripts that were differentially expressed (fold-changeââ¥â2) due to an N-deficiency. Among them, 1,158 were differentially expressed in the leaf sheaths (548 up-regulated and 610 down-regulated) and 492 in the roots (276 up, 216 down).
Project description:In this study, we used RNA-Seq to understand the mechanisms of Cd toxicity, cellular detoxification and protection pathways in response to Cd in rice roots. To gain additional insight into the rice transcriptomic response to environmental Cd stress, 15-day-old rice seedlings were treated with 10 or 100 μM solutions of Cd2+, or without Cd (control), for 24 h, at which point root samples were harvested and labeled as Cd+, Cd++, and control, respectively. These samples were used for 101 bp paired-end (PE) deep sequencing on an Illumina HiSeq 2500 platform.