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: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:Microarray analysis is a technique that can be employed to provide expression profiles of single genes and a new insight to elucidate the biological mechanisms responsible for fruit development. To evaluate expression of genes mostly engaged in fruit development between P. mume and P. armeniaca, we first identified differentially expressed transcripts along the entire fruit life cycle by using microarrays spotted with 10,641 ESTs collected from P. mume and other Prunus EST sequences. A total of 1,418 ESTs were selected after quality control of microarray spots and analyzed for differential gene expression patterns during fruit development of P. mume and P. armeniaca. Among them, 707 up-regulated and 711 down-regulated differentially expressed genes showing more than 2.0-fold differences in expression level were annotated by GO based on biological processes, molecular functions and cellular components. These differentially expressed genes were found to be involved in several important pathways of carbohydrate metabolism, galactose metabolism, starch and sucrose metabolism, and biosynthesis of other secondary metabolites via KEGG, which could provide detailed information on the fruit quality differences during development and ripening. With the obtained results, we provide a practical database for comprehensive understanding of molecular events during fruit development and also lay the theoretical foundation for the cloning of genes involved in a series of important rate-limiting enzymes in the vital metabolic pathways during the fruit development.
Project description:Microarray analysis is a technique that can be employed to provide expression profiles of single genes and a new insight to elucidate the biological mechanisms responsible for fruit development. To evaluate expression of genes mostly engaged in fruit development between P. mume and P. armeniaca, we first identified differentially expressed transcripts along the entire fruit life cycle by using microarrays spotted with 10,641 ESTs collected from P. mume and other Prunus EST sequences. A total of 1,418 ESTs were selected after quality control of microarray spots and analyzed for differential gene expression patterns during fruit development of P. mume and P. armeniaca. Among them, 707 up-regulated and 711 down-regulated differentially expressed genes showing more than 2.0-fold differences in expression level were annotated by GO based on biological processes, molecular functions and cellular components. These differentially expressed genes were found to be involved in several important pathways of carbohydrate metabolism, galactose metabolism, starch and sucrose metabolism, and biosynthesis of other secondary metabolites via KEGG, which could provide detailed information on the fruit quality differences during development and ripening. With the obtained results, we provide a practical database for comprehensive understanding of molecular events during fruit development and also lay the theoretical foundation for the cloning of genes involved in a series of important rate-limiting enzymes in the vital metabolic pathways during the fruit development. Fruits from 4 cultivar at different stages, replicated 2 times
Project description:The TCP4 transcription factor plays an important role in plant growth and development, especially in flower development. PmTCP4 is involved in the process of pistil abortion in Japanese apricot, but its molecular mechanism, particularly the DNA binding sites and co-regulatory genes, are quite unknown. Therefore, to identify the genome-wide binding sites of PmTCP4 transcription factors and their co-regulatory genes, chromatin immunoprecipitation sequencing (ChIPSeq) was carried out. ChIP-Seq data produced the maximum enriched peaks in two Japanese apricot cultivars ‘Daqiandi’ (DQD) and ‘Longyan’ (LY), which showed that the majority ofDNA-protein interactions are relevant and have a significant function in binding sites. Moreover, 720 and 251 peak-associated genes regulated by PmTCP4 were identified in DQD and LY, respectively, and most of them were involved in the flower and pistil development process. Furthermore, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that photosynthesis and oxidative phosphorylation were the most enriched pathways in both cultivars and all identified genes related to these pathways were down-regulated. This study will provide a reference for a better understanding of the PmTCP4 regulatory mechanism during pistil abortion in Japanese apricot.
Project description:454-pyrosequencing of the Transcriptome in Leaf and Flower Buds of Japanese Apricot (Prunus mume Sieb. et Zucc.) at Different Dormant Stages