Project description:Understanding the regulation of lipid metabolism is vital for genetic engineering of Brassica napus (B. napus) to increase oil yield or modify oil composition. We report the application of Illumina Hiseq 2000 for transcriptome profiling of seeds of B. napus at different developmental stages, which may uncover the dynamic changes in lipid metabolism and reveal key genes involved in lipid biosynthesis and degradation. Total RNA from developing seeds at 2, 4, 6, and 8 weeks after pollination (WAP) were isolated and sequenced separately. The gene expression levels of all samples were quantified and normalized by the DESeq normalization. We found that the biosynthesis of fatty acids is a dominant cellular process from 2 to 6 WAP, while the degradation mainly happens after 6 WAP. Two genes, encoding for acetyl-CoA carboxylase and acyl-ACP desaturase, might be critical for fatty acid biosynthesis in oil rape seeds. This study provides insight into the mechanism underlying lipid metabolism and reveals candidate genes that are worthy of further investigation for their values in genetic engineering of B. napus. Whole Transcriptome profiling of developing Brassica napus seeds at 2, 4, 6, 8 WAP by RNA sequencing using Illumina HiSeq 2000.
Project description:Understanding the regulation of lipid metabolism is vital for genetic engineering of Brassica napus (B. napus) to increase oil yield or modify oil composition. We report the application of Illumina Hiseq 2000 for transcriptome profiling of seeds of B. napus at different developmental stages, which may uncover the dynamic changes in lipid metabolism and reveal key genes involved in lipid biosynthesis and degradation. Total RNA from developing seeds at 2, 4, 6, and 8 weeks after pollination (WAP) were isolated and sequenced separately. The gene expression levels of all samples were quantified and normalized by the DESeq normalization. We found that the biosynthesis of fatty acids is a dominant cellular process from 2 to 6 WAP, while the degradation mainly happens after 6 WAP. Two genes, encoding for acetyl-CoA carboxylase and acyl-ACP desaturase, might be critical for fatty acid biosynthesis in oil rape seeds. This study provides insight into the mechanism underlying lipid metabolism and reveals candidate genes that are worthy of further investigation for their values in genetic engineering of B. napus.
Project description:mRNA expression profiling of the embryo, endosperm (micropylar, peripheral, chalazal), and seed coat (outer, inner, chalazal, chalazal proliferating tissue) of the developing Brassica napus seed. Tissues were isolated using laser microdissection (LMD) from Brassica napus seeds at the globular, heart, and mature green stages of seed development.
Project description:High temperature stress results in yield loss and alterations to seed composition during seed filling in oilseed rape (Brassica napus). However, the mechanism underlying this heat response is poorly understood. In this study, we employed a microarray analysis with silique walls and seeds from the developing siliques (20 days after flowering) of Brassica napus that had undergone heat stress.
Project description:Gene expression profiles during seed development and fatty acid (FA) metabolism, as well as the relevant regulation, of Brassica napus were studied through multiple high-throughput genomic approaches. Serial Analysis of Gene Expression (SAGE) using seed materials obtained a total of 68,718 tags, of which 23,897 were unique and 503 tags were functionally identified, and revealed the transcriptome of approximately 35,000 transcripts in B. napus developing seeds. Further, ~22,000 independent ESTs were obtained by large-scale sequencing using immature embryos at different stages, and 8343 uni-ESTs and 3355 full-length cDNAs were identified respectively, resulting in the systemic identification of B. napus FA biosynthesis-related genes. Gene expression profiles were further studied employing cDNA chip hybridization to reveal the global regulatory network of FA metabolism in developing seeds. Together with the analysis on FA amounts and composition, it was shown that 17-21 days after pollination (DAP) was a crucial stage for transition of seed to sink tissue. High expressions of FA biosynthesis-related genes and transition of FA components are mainly at stages 21 DAP or 21-25 DAP respectively. In addition, compared to Arabidopsis, more critical roles of starch metabolism are detected for B. napus seed FA metabolism and storage components accumulation. Crucial effects of starch metabolism, carbon flux, oxidative pentose phosphate pathway (OPPP), photosynthesis, and other regulators in FA metabolism were discussed. Keywords: Brassica napus, immature seed, SAGE, EST, cDNA microarray
Project description:High temperature stress results in yield loss and alterations to seed composition during seed filling in oilseed rape (Brassica napus). However, the mechanism underlying this heat response is poorly understood. In this study, we employed a microarray analysis with silique walls and seeds from the developing siliques (20 days after flowering) of Brassica napus that had undergone heat stress. Two-condition experiment, control vs heat stress, 2 time points
Project description:MicroRNAs (miRNAs) are important post-transcriptional regulators of plant development and seed formation. In Brassica napus, an important edible oil crop, valuable lipids are synthesized and stored in specific seed tissues during embryogenesis. The miRNA transcriptome of B. napus is currently poorly characterized, especially at different seed developmental stages. This work aims to describe the miRNAome of developing seeds of B. napus by identifying plant-conserved and novel miRNAs and comparing miRNA abundance in mature versus developing seeds. A total of 62 miRNA families were detected through a computational analysis of a large number of reads obtained from deep sequencing two small RNA and two RNA-seq libraries of (i) pooled immature developing stages and (ii) mature B. napus seeds. Among these miRNA families, 17 families are currently known to exist in B. napus; additionally, 32 families not reported in B. napus but conserved in other plant species were identified by alignment with known plant mature miRNAs. The contigs from the assembled mRNA-seq data allowed for a search for putative new precursors and led to the identification of 13 novel miRNA families. Differential expression between the libraries was determined through a statistical analysis of normalized miRNA reads and revealed several miRNAs and isomiRNAs that were more abundant during the developing stages. The predicted miRNA target genes encode a broad range of proteins related to seed development and energy storage. This work presents a comprehensive study of the miRNA transcriptome of B. napus seeds and will provide a basis for future research on more targeted studies of individual miRNAs and their functions in embryogenesis, seed maturation and lipid accumulation in B. napus. RNA profiles in 2 different seed libraries (mature seeds and a pool of developing seed stages) of Brassica napus by deep sequencing (Illumina HiSeq2000).
Project description:MicroRNAs (miRNAs) are important post-transcriptional regulators of plant development and seed formation. In Brassica napus, an important edible oil crop, valuable lipids are synthesized and stored in specific seed tissues during embryogenesis. The miRNA transcriptome of B. napus is currently poorly characterized, especially at different seed developmental stages. This work aims to describe the miRNAome of developing seeds of B. napus by identifying plant-conserved and novel miRNAs and comparing miRNA abundance in mature versus developing seeds. A total of 62 miRNA families were detected through a computational analysis of a large number of reads obtained from deep sequencing two small RNA and two RNA-seq libraries of (i) pooled immature developing stages and (ii) mature B. napus seeds. Among these miRNA families, 17 families are currently known to exist in B. napus; additionally, 32 families not reported in B. napus but conserved in other plant species were identified by alignment with known plant mature miRNAs. The contigs from the assembled mRNA-seq data allowed for a search for putative new precursors and led to the identification of 13 novel miRNA families. Differential expression between the libraries was determined through a statistical analysis of normalized miRNA reads and revealed several miRNAs and isomiRNAs that were more abundant during the developing stages. The predicted miRNA target genes encode a broad range of proteins related to seed development and energy storage. This work presents a comprehensive study of the miRNA transcriptome of B. napus seeds and will provide a basis for future research on more targeted studies of individual miRNAs and their functions in embryogenesis, seed maturation and lipid accumulation in B. napus. microRNA profiles in 2 different seed libraries (mature seeds and a pool of developing seed stages) of Brassica napus by deep sequencing (Illumina HiSeq2000).
Project description:To broadly identify genes regulated by Transparent Testa16 in Brassica napus In order to broadly identify genes regulated by BnTT16s, microarray technology was employed to compare gene expression levels in developing seeds (2-DAP) of Bntt16 RNAi and wild-type plants.
Project description:Identification of differentially expressed genes in seeds and silique walls at the seed-filling stage in Brassica napus through transcriptional profiling