Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral buds through the course of the year allowing for identification of changing developmental signals. We used RNA samples from floral buds, with bud scale removed, in the upper crown of a sexually mature Populus deltoides tree 2 hours after sunrise. Three independent samples of floral bud tissues with bud scales removes were collected from the upper crown of a single sexually mature male tree. RNA was extracted from tissues and hybridized on Affymetrix Genechip Poplar Genome Array.
Project description:We conducted micro-array analysis to quantify the global transcriptome variations in floral buds through the course of the year allowing for identification of changing developmental signals. We used RNA samples from floral buds, with bud scale removed, in the upper crown of a sexually mature Populus deltoides tree 2 hours after sunrise.
Project description:During embryogenesis, the pancreas develops from separate dorsal and ventral buds, which fuse to form the mature pancreas. Little is known about the functional differences between these two buds or the relative contribution of cells derived from each portion to the pancreas after fusion. To follow the fate of dorsal or ventral bud derived cells in the pancreas after fusion, we produced chimeric Elas-GFP transgenic/wild type embryos in which either dorsal or ventral pancreatic bud cells expressed GFP. We found that ventral pancreatic cells migrate extensively into the dorsal pancreas after fusion, whereas the converse does not occur. Moreover, we found that annular pancreatic tissue is composed exclusively of ventral pancreas derived cells. To identify ventral pancreas specific genes that may play a role in pancreatic bud fusion, we isolated individual dorsal and ventral pancreatic buds, prior to fusion, from stage 38/39 Xenopus laevis tadpoles and compared their gene expression profiles. Morpholino-mediated knockdown of one of these ventral specific genes, transmembrane 4 superfamily member 3 (tm4sf3), inhibited dorsal-ventral pancreatic bud fusion as well as acinar cell differentiation. Conversely, overexpression of tm4sf3 promoted the development of annular pancreas. Our results are the first to define molecular and behavioral differences between the dorsal and ventral pancreas, and suggest an unexpected role for the ventral pancreas in pancreatic bud fusion. Keywords: Developmental genomics
Project description:Bud dormancy is a critical developmental process for perennial plant survival, and also an important physiological phase that affects the next seasonM-bM-^@M-^Ys growth of temperate fruit trees. Bud dormancy is regulated by multiple genetic factors, and affected by various environmental factors, tree age and vigor. To understand molecular mechanism of bud dormancy in Japanese apricot (Prunus mume Sieb. et Zucc.), we constructed a custom oligo DNA microarray covering the Japanese apricot dormant bud ESTs referring to peach (P. persica) genome sequence. Because endodormancy release is a chilling temperature-dependent physiological event, genes showing chilling-mediated differential expression patterns are candidates to control endodormancy release. Using the microarray constructed in this study, we monitored gene expression changes of dormant vegetative buds of Japanese apricot during prolonged artificial chilling exposure. In addition, we analyzed seasonal gene expression changes. M-bM-^@M-^XNankoM-bM-^@M-^Y vegetative buds collected in November, and those exposed to chilling for 40 or 60 days were used as microarray samples. Among the 58539 different unigene probes, 2345 and 1059 genes were identified as being more than two-fold up-regulated and down-regulated, respectively, following chilling exposure for 60 days (P value < 0.05). The down-regulated genes included P. mume DORMANCY-ASSOCIATED MADS-box genes, which supported the previous quantitative RT-PCR and EST analyses showing that these genes are repressed by prolonged chilling treatments. The genes encoding lipoxygenase were remarkably up-regulated by prolonged chilling. Cluster analysis suggested that the expression of the genes showing expression changes by artificial chilling exposure were coordinately regulated by seasonal changes. Our parametric analysis of gene set enrichment suggested that genes related to jasmonic acid (JA) and oxylipin biosynthesis and metabolic processes were significantly up-regulated by prolonged chilling, whereas genes related to circadian rhythm were significantly down-regulated. The results obtained from the microarray analyses were verified by quantitative RT-PCR analysis of selected genes. Taken together, this study raised the possibility that the microarray platform constructed in this study is applicable for deeper understanding of molecular network related to agronomically important bud phisiologies including dormancy release. In this study, we used chilling exposed bud samples (0, 40, 60 days starting at November) and seasonal monthly bud samples (June to March). For the samples in dataset 1 (three different time points during chilling treatment), three technical replicates (60K M-CM-^W 3 per sample) with three biological replicates were averaged, whereas three technical replicates were averaged for the samples in dataset 2 (10 different seasonal time points)
Project description:Bud dormancy is a critical developmental process for perennial plant survival, and also an important physiological phase that affects the next season’s growth of temperate fruit trees. Bud dormancy is regulated by multiple genetic factors, and affected by various environmental factors, tree age and vigor. To understand molecular mechanism of bud dormancy in Japanese apricot (Prunus mume Sieb. et Zucc.), we constructed a custom oligo DNA microarray covering the Japanese apricot dormant bud ESTs referring to peach (P. persica) genome sequence. Because endodormancy release is a chilling temperature-dependent physiological event, genes showing chilling-mediated differential expression patterns are candidates to control endodormancy release. Using the microarray constructed in this study, we monitored gene expression changes of dormant vegetative buds of Japanese apricot during prolonged artificial chilling exposure. In addition, we analyzed seasonal gene expression changes. ‘Nanko’ vegetative buds collected in November, and those exposed to chilling for 40 or 60 days were used as microarray samples. Among the 58539 different unigene probes, 2345 and 1059 genes were identified as being more than two-fold up-regulated and down-regulated, respectively, following chilling exposure for 60 days (P value < 0.05). The down-regulated genes included P. mume DORMANCY-ASSOCIATED MADS-box genes, which supported the previous quantitative RT-PCR and EST analyses showing that these genes are repressed by prolonged chilling treatments. The genes encoding lipoxygenase were remarkably up-regulated by prolonged chilling. Cluster analysis suggested that the expression of the genes showing expression changes by artificial chilling exposure were coordinately regulated by seasonal changes. Our parametric analysis of gene set enrichment suggested that genes related to jasmonic acid (JA) and oxylipin biosynthesis and metabolic processes were significantly up-regulated by prolonged chilling, whereas genes related to circadian rhythm were significantly down-regulated. The results obtained from the microarray analyses were verified by quantitative RT-PCR analysis of selected genes. Taken together, this study raised the possibility that the microarray platform constructed in this study is applicable for deeper understanding of molecular network related to agronomically important bud phisiologies including dormancy release.
Project description:During embryogenesis, the pancreas develops from separate dorsal and ventral buds, which fuse to form the mature pancreas. Little is known about the functional differences between these two buds or the relative contribution of cells derived from each portion to the pancreas after fusion. To follow the fate of dorsal or ventral bud derived cells in the pancreas after fusion, we produced chimeric Elas-GFP transgenic/wild type embryos in which either dorsal or ventral pancreatic bud cells expressed GFP. We found that ventral pancreatic cells migrate extensively into the dorsal pancreas after fusion, whereas the converse does not occur. Moreover, we found that annular pancreatic tissue is composed exclusively of ventral pancreas derived cells. To identify ventral pancreas specific genes that may play a role in pancreatic bud fusion, we isolated individual dorsal and ventral pancreatic buds, prior to fusion, from stage 38/39 Xenopus laevis tadpoles and compared their gene expression profiles. Morpholino-mediated knockdown of one of these ventral specific genes, transmembrane 4 superfamily member 3 (tm4sf3), inhibited dorsal-ventral pancreatic bud fusion as well as acinar cell differentiation. Conversely, overexpression of tm4sf3 promoted the development of annular pancreas. Our results are the first to define molecular and behavioral differences between the dorsal and ventral pancreas, and suggest an unexpected role for the ventral pancreas in pancreatic bud fusion. Experiment Overall Design: We analyzed two samples of dorsal and two samples of ventral pancreatic buds.
Project description:Aims: To determine the changes in the Arabidopsis axillary bud transcriptome in response to changes in the red light (R) to far red light (FR) ratio (R:FR). Background: The branching habit of plants is a key determinant of overall plant form and function with great relevance to modern agriculture. Shade signals transduced by phytochromes are major regulators of axillary bud outgrowth, and in turn control branching in both natural and agricultural environments. To continue our investigations into the regulation of branching by R:FR, we have developed a system using supplemental FR LEDs to tightly control the outgrowth of Arabidopsis axillary buds. Depending on the position of the bud in the rosette, outgrowth is either repressed (uppermost bud) or rapidly promoted (bud in the axil of the third leaf down) by the transition from low to high R:FR. Treatment: Two separate experiments were conducted to evaluate the effects of R:FR on transcriptome changes in the uppermost rosette bud (bud n) and the axillary bud in the axil of the third leaf from the top (bud n-2). WT Col-60000 was used as the experimental material. Plants were grown individually in 25 by 50 mm tubes and watered and fertilized optimally. Plants were grown in a split growth chamber (providing uniform temperature and PPFD but allowing for differential R:FR) with 18 h photoperiods (185 Moles m-2 s-1 PPFD provided by T12 VHO CW fluorescent lamps) and 24 C/18 C day/night temperatures. One day after sowing, the R:FR was reduced on both sides of the chamber from 3.5 to 0.08 using FR LEDs fixed in clear overhead arrays. Prior to anthesis, the plants were matched and split into two treatment groups. In experiment 1, the FR source for one of the groups was switched off at 12:00 pm on the day of anthesis, causing the R:FR to increase to 3.5. Unelongated axillary buds in the axil of the uppermost leaves (approx. 2.5 mm long) were harvested for RNA preparation from both groups (low and transiently increased R:FR) 3 h after changing the R:FR. Each treatment was composed of three biological replicates, each containing buds from about 15-18 plants. Experiment 2 was conducted exactly the same as experiment 1, except the R:FR was altered 3 days after anthesis and the unelongated axillary buds in the axils of the third leaves down (approx. 1 mm long) were harvested for RNA preparation. 12 samples (3 bud n and low R:FR, 3 bud n and high R:FR, 3 bud n-2 and low R:FR, 3 bud n-2 and high R:FR) were used in this experiment.
Project description:Holm oak (Quercus ilex) is the most important and representative specie of the Mediterranean forest and of the Spanish agrosilvo-pastoral ecosystem “Dehesa”. Despite its environmental and economic interest, Holm oak is still an orphan species whose biology is very little known, especially at the molecular level. In this research, we have performed a shotgun proteomic approach (nLC-MSMS, Orbitrap) to analyze the Holm oak proteome, using, as starting material, a pool generated by mixing equal amounts of homogenized tissue, including embryo, cotyledons (from mature acorns), and leaves and roots (from 6-month old plantlets grown in a greenhouse under environmental conditions). The proteome generated will be the bases of further studies on population variability, growth, development and responses to stresses in this species.