Project description:Three rice major tissues, namely flag leaf, shoot and panicle, were involved in this study. Each tissue had two kinds stress treatment, drought and high salinity, in 3 different time courses. For drought treated samples, an additional water recovery was applied. Each experiment had three replicates. Keywords: Comparison of gene expression in three tissues with stress treatment and without treatment To globally elucidate potential genes involved in drought and high-salinity stresses responses in rice, an oligomer microarray covering 37,132 genes including cDNA or EST supported and putative genes was applied to study the expression profiling of shoot, flag leaf, and panicle under drought or high-salinity treatment. Three rice major tissues, namely flag leaf, shoot and panicle, were involved in this study. Each tissue had two kinds stress treatment, drought and high salinity, in 3 different time courses. For drought treated samples, an additional water recovery was applied. Each experiment had three replicates.
Project description:To comprehend the gene expression profile in rice flag leaf under high temperature, Agilent 4×44k rice oligo microarray experiments were carried out using rice flag leaf of reproductive stage at 0 min, 20 min, 60 min, 2 hr, 4 hr, and 8 hr after the treatment of 40 degree centigrade, and the significantly expressed genes mainly involved in transcriptional regulation, transport, protein binding, antioxidant, and stress response were identified. Among them, the predominant transcription factor gene families were Hsf, NAC, AP2/ERF, WRKY, MYB, and C2H2. KMC analysis discovered the time-dependent gene expression pattern under heat. The metabolism pathway analysis demonstrated that, under heat treatment, glycolysis and ubiquitin-proteasome was enhanced, and TCA, gluconeogenesis, the secondary metabolism and light-reaction in the photosystem was dramatically repressed, which revealed the great importance of maintaining primary metabolism and protein homeostasis in response to heat in rice flag leaf.
Project description:Three rice major tissues, namely flag leaf, shoot and panicle, were involved in this study. Each tissue had two kinds stress treatment, drought and high salinity, in 3 different time courses. For drought treated samples, an additional water recovery was applied. Each experiment had three replicates. Keywords: Comparison of gene expression in three tissues with stress treatment and without treatment
Project description:To comprehend the gene expression profile in rice flag leaf under high temperature, Agilent 4M-CM-^W44k rice oligo microarray experiments were carried out using rice flag leaf of reproductive stage at 0 min, 20 min, 60 min, 2 hr, 4 hr, and 8 hr after the treatment of 40 degree centigrade, and the significantly expressed genes mainly involved in transcriptional regulation, transport, protein binding, antioxidant, and stress response were identified. Among them, the predominant transcription factor gene families were Hsf, NAC, AP2/ERF, WRKY, MYB, and C2H2. KMC analysis discovered the time-dependent gene expression pattern under heat. The metabolism pathway analysis demonstrated that, under heat treatment, glycolysis and ubiquitin-proteasome was enhanced, and TCA, gluconeogenesis, the secondary metabolism and light-reaction in the photosystem was dramatically repressed, which revealed the great importance of maintaining primary metabolism and protein homeostasis in response to heat in rice flag leaf. Heat shock induced gene expression in rice flag leaf of reproductive stage was measured at 0 min, 20 min, 60 min, 2 hr, 4 hr, and 8 hr after the treatment of 40 degree centigrade in plant growth chamber. Two independent replicate experiments were performed at each time point.
Project description:Leaf rolling and discoloration are two chilling injury symptoms that are widely adopted as indicators for evaluation of cold tolerance at the seedling stage in rice, respectively. However, their relationship has not been well investigated, in particular the mechanism on how low temperature causes leaf rolling at a genome-wide level. In this study, a cold-tolerant japonica cultivar Lijiangxintuanheigu and a cold-sensitive indica cultivar Sanhuangzhan-2 were subjected to different low temperature treatments and physiological and genome-wide gene expression analysis were conducted. Our results showed that leaf rolling happened at temperatures lower than 11℃, but discoloration appeared at moderately low temperatures, such as 13℃. Chlorophyll contents of the two cultivars significantly decreased under 13℃, but didn’t change under 11℃. Contrastly, their relative water contents and the relative electrolyte leakages decreased significantly. Genome-wide gene expression profiling of LTH revealed that the calcium signaling related genes and the genes related to ABA degradation significantly changed under 11℃. Moreover, numerous genes in DREB, MYB, bZIP, NAC, Zin finger, bHLH, WRKY gene families were differently expressed. Furthermore, many aquaporin genes, the key genes in trehalose and starch synthesis were down-regulated under 11℃. These results suggest that the two chilling injury symptoms are controlled by different mechanisms. Cold-induced leaf rolling is associated with calcium and ABA signaling pathways, and subjected to regulation of multiple transcription regulators. The suppression of aquaporin genes and reduced accumulation of soluble sugars under cold stress result in reduction of water potential in cells and consequently, leaf rolling.
Project description:We analyzed the transcriptome profiles for rice grain from heat-tolerant and -sensitive lines in response to high night temperatures at the early milky stage using the Illumina Sequencing method. On the 8th day after the labeled florets flowered, plants with the same label were transferred to chambers and maintained at a temperature of 38.0â±â0.5°C (treatment) or 25.0â±â0.5°C (control) for the dark period (10 h), and 26.0â±â0.5°C (both treatment and control) for the light period (14 h). Three biological replicates of the temperature treatments were grown under the same conditions. After 48 h of treatment, samples containing 45 grains with labels from the same region (middle to bottom part) of labelled ears were harvested, packed in aluminum foil, and flash-frozen in liquid nitrogen until further use. A total of 12 rice grain samples were harvested, i.e., controls (TC1, TC2 and TC3) and treatments (TT1, TT2 and TT3) of the three biological replicates of the heat-tolerant line, and controls (SC1, SC2 and SC3) and treatments (ST1, ST2 and ST3) of the three biological replicates of the heat-sensitive line.
Project description:Higher temperature conditions during the final stages of rice seed development (seed filling and maturation) are known to cause damage to both rice yield and rice kernel quality. Japan, especially western and central parts, has seen record high temperatures in the last decade, and the rice kernel quality has decreased; specifically a reduction the first-grade of rice has been seen. In this study, we specifically looked at the harvested rice in a town of the central Kanto-plains (Japan) during the year 2010, which saw day-time temperatures go above the critical limits ranging from 34 to 38C at the final stages of seed development and maturity to investigate high-temperature effects in the actual field condition. Three sets of dry mature rice seeds (commercial) were obtained Japan Agriculture (JA Zen-Noh) branch in Ami-town of Ibaraki prefecture in September 2010, as grade 1 (labeled as Y1), grade 2 (labeled as Y2), and grade 3 (out-of-grade, labeled as Y3). The research objective was to examine in particular alterations in gene expressions genome-wide in grade 2 (Y2) and grade 3 (Y3) seeds over the grade 1 (Y1) following the high-temperature spike using a high-throughput omic-approach DNA microarray (Agilent 4 x 44K rice oligo DNA chip) in conjunction with MapMan bioinformatics analysis. Rice seed quality analysis revealed, as expected, low quality in Y3 > Y2 over Y1, in taste, amylose, protein and fatty acid degree, but not in water content. Transcriptome profiling data revealed 124 and 373 up-regulated and 106 and 129 down-regulated genes in Y2 and Y3, respectively. Bioinformatics analysis of differentially expressed genes revealed changes in function of genes related to metabolism, including starch metabolism (e.g., alpha amylase), defense/stress response, fatty acid biosynthesis and hormones. This research provides for the first time the seed transcriptome profile for the classified low grades (2 and out-of-grade) of rice under an actual stressed environmental condition of high temperature.