Project description:The purposes of this study are to compare euploid B. napus cv. “Oro” and the C1 nullisomics transcriptome profiling (RNA-seq) and quantitative reverse transcription polymerase chain reaction (qRT–PCR) methods and to evaluate protocols for optimal high-throughput data analysis. Methods: Leaves mRNA profiles of 30-day-old euploid B. napus cv. “Oro” and the C1 nullisomics were generated by deep sequencing, in triplicate, using Illumina. The sequence reads that passed quality filters were analyzed at the transcript isoform level with two methods. qRT–PCR validation was performed. Results: After the high-throughput sequencing, each sample generated 7.2G Clean data on average and the 44.6-53.8 million clean reads were generated. Our study represents detailed analysis of leaves transcriptomes in euploid B. napus and nullisomic, with biologic replicates, generated by RNA-seq technology for comparative investigations of expression profiles. Our results show that Dose complementary effect exists between highly homologous genes, and partial loss of C subgenomic chromosome will lead to increased expression of A genome.
Project description:Using a combination of laser microdissection coupled with high-throughput RNA sequencing we profiled the epidermis, mesophyll and vascular leaf tissue layers in response to S. sclerotiorum. We find individual tissue layers reveal distinct defense processes, as well as processes enriched shared between all three layers
Project description:The hemibiotrophic fungal pathogen Leptosphaeria maculans is the causal agent of blackleg disease in Brassica napus (canola, oilseed rape) and causes significant losses in crop yields worldwide. While genetic resistance has been used to mitigate the disease, little information about the genes and gene regulatory networks underlying blackleg resistance is currently available. High-throughput RNA sequencing and rigorous bioinformatics approaches revealed dynamic changes in the host transcriptome and identified plant defense pathways specific to the host-pathogen incompatible LepR1-AvrLepR1 interaction.
Project description:We profiled the gene regulatory landscape of Brassica napus reproductive development using RNA sequencing. Comparative analysis of this nascent allotetraploid across the plant lifecycle revealed the contribution of each subgenome to plant reproduction. Global mRNA profiling across reproductive development revealed lower accumulation of C subgenome transcripts relative to the A subgenome. Subgenome-specific transcriptional networks identified distinct transcription factor families enriched in each of the A and C subgenome in early seed development. Analysis of a tissue specific transcriptome of early seed development revealed transcription factors predicted to be regulators encoded by the A subgenome are expressed primarily in the seed coat whereas regulators encoded by the C subgenome were expressed primarily in the embryo. Whole genome transcription factor networks identified BZIP11 as an essential regulator of early B. napus seed development. Knockdown of BZIP11 using RNA interference resulted in knockdown of predicted target genes, and a reproductive-lethal phenotype. Our data indicate that subgenome bias are characteristic features of the B. napus seed throughout its development, and that such bias might not be universal across the embryo, endosperm, and seed coat of the developing seed. We also find that examining transcriptional networks spanning both the A and C genomes of the whole B. napus seed can identify valuable targets for seed development research. We suggest that-omics level approaches to studying gene regulation in B. napus can benefit from both broad and high-resolution analyses.
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:<p>Genome-wide association studies (GWAS) identified thousands of genetic loci associated with complex plant traits, including many traits of agronomical importance. However, functional interpretation of GWAS results remains challenging because of large candidate regions due to linkage disequilibrium. High-throughput omics technologies, such as genomics, transcriptomics, proteomics, and metabolomics open new avenues for integrative systems biological analyses and help to nominate systems information supported (prime) candidate genes. In the present study, we capitalize on a diverse canola population with spring-type 477 lines which was previously analysed by high-throughput phenotyping (Knoch et al., 2020), and by RNA sequencing and metabolite profiling for multi-omics-based hybrid performance prediction (Knoch et al., 2021). We deepened the phenotypic data analysis, now providing 123 time-resolved image-based traits, to gain insight into the complex relations during early vegetative growth and re-analysed the transcriptome data based on the latest Darmor-bzh v10 genome assembly (Rousseau-Gueutin et al., 2020). Genome-wide association testing revealed 61,298 robust quantitative trait loci (QTL) including 187 metabolite-QTL, 56,814 expression-QTL, and 4,297 phenotypic QTL, many clustered in pronounced hotspots. Combining information about QTL colocalisation across omics layers and correlations between omics features allowed us to discover prime candidate genes for metabolic and vegetative growth variation. Prioritized candidate genes for early biomass accumulation include A06p05760.1_BnaDAR (PIAL1), A10p16280.1_BnaDAR, C07p48260.1_BnaDAR (PRL1), and C07p48510.1_BnaDAR (CLPR4). Moreover, we observed unequal effects of the Brassica A and C subgenomes on early biomass production.</p><p><br></p>
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.