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: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:Cotton fiber is actually unicellular trichome, therefor its length is really hard to be modified but very meaningful to fiber quality and yield. We have reported the function of the second RRM domain of Oryza sativa FCA in rice cell size regulation. Data shows it is highly conserved across dicotyledonous and monocotyledonous plants. Here we provide evidence showing that the second RRM domain of Brassica napus FCA worked in Gossypium hirsutum, leading to the enlargement of multiple types of cells, such as pollen, cotyledon petiole and cotton fiber. In the transgenic cotton, the length of unicellular cotton fiber increased by about 10% and fiber yield per plant also showed a dramatic increase, ranging from 35% to 66%, over the control. Thus, this RRM domain may be an ancient and common cell size regulator and has great economic value on cotton industry.
Project description:We establish global maps of regulatory elements and chromatin states and their dynamics, for both the whole and subgenomes of four tissue types (young leaf, flower bud, silique, and root) of two B. napus lines. Approximately 52 % of the genome was annotated with different epigenomic signals. We also uncover a new bivalent chromatin state in B. napus and suggest its key roles in regulating tissue-specific gene expression. Furthermore, we observe that different types of duplicated genes have differential patterns of histone modifications, DNA methylation, and selection pressures. Together, we provide valuable epigenetic data resources of allopolyploid B. napus and reveal the central role of epigenomic information in understanding transcriptional regulation in polyploid plants.
Project description:We establish global maps of regulatory elements and chromatin states and their dynamics, for both the whole and subgenomes of four tissue types (young leaf, flower bud, silique, and root) of two B. napus lines. Approximately 52 % of the genome was annotated with different epigenomic signals. We also uncover a new bivalent chromatin state in B. napus and suggest its key roles in regulating tissue-specific gene expression. Furthermore, we observe that different types of duplicated genes have differential patterns of histone modifications, DNA methylation, and selection pressures. Together, we provide valuable epigenetic data resources of allopolyploid B. napus and reveal the central role of epigenomic information in understanding transcriptional regulation in polyploid plants.
Project description:Cotton fiber is actually unicellular trichome, therefor its length is really hard to be modified but very meaningful to fiber quality and yield. We have reported the function of the second RRM domain of Oryza sativa FCA in rice cell size regulation. Data shows it is highly conserved across dicotyledonous and monocotyledonous plants. Here we provide evidence showing that the second RRM domain of Brassica napus FCA worked in Gossypium hirsutum, leading to the enlargement of multiple types of cells, such as pollen, cotyledon petiole and cotton fiber. In the transgenic cotton, the length of unicellular cotton fiber increased by about 10% and fiber yield per plant also showed a dramatic increase, ranging from 35% to 66%, over the control. Thus, this RRM domain may be an ancient and common cell size regulator and has great economic value on cotton industry. FCA encodes a strong promoter of the transition to flowering in Arabidopsis thaliana, which contains two RRM (RNA recognition motif) domain and a WW protein interaction domain (Macknight et al., 1997). We have previously found that cell size and yield of rice (Oryza sativa) can be increased by ectopic expression of the first RRM domain of OsFCA (Hong et al., 2007). The second RRM domain of OsFCA can also increase cell size (Attia et al., 2005), suggesting OsFCA-RRMs each play a role in homeostatic cell size regulation. We designate them as Oryza sativa cell size RRM 1 (Os-csRRM1) and Oryza sativa cell size RRM 2 (Os-csRRM2), respectively. Both of them exhibit a high degree of evolutionary conservation in plant. For Os-csRRM2, significant homology was observed in Triticum aestivum (90% identity), Hordeum vulgare (90% identity), Lolium perenne (82% identity), Zea mays (81% identity),Ricinus communis (76% identity), Vitis vinifera (68% identity), Arabidopsis thaliana (68% identity) and Brassica napus (64% identity) (Fig. 1). The high degree of conservation suggests that this RRM domain might have similar function in different plants. Indeed, we observed that overexpression of Bn-csRRM2 also increased the cell size of B. napus (unpublished data). As cotton fiber length is a key factor in cotton yield and quality, we investigated whether this attribute could be enhanced by constitutive expression of Bn-csRRM2. Transgenic and wild-type cotton were grown in same condition. The leaves of 25 day and 45 day plants were harvested for microarray analysis. RNA samples were isolated from 3 biological replications using TRIzol (Invitrogen) as described by the manufacturer. Microarray analyses were carried out using Agilent Cotton Gene Expression Microarray (G2519F-022523). Microarrays were scanned on Agilent Technologies Scanner G2505C and data points were extracted using Agilent Feature Extraction software (Version 10.7.1.1). Comparisons were made between transgenic samples and their corresponding wild-type samples.
Project description:Differentially expressed genes in developing pods of CpFatB4- and CpFatB5- expressing transgenic Brassica napus in seed specific manner were investigated using RNA-seq method at 8, 25, and 45 days after fertilization
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:We establish global maps of regulatory elements and chromatin states and their dynamics, for both the whole and subgenomes of four tissue types (young leaf, flower bud, silique, and root) of two B. napus lines. Approximately 52 % of the genome was annotated with different epigenomic signals. We also uncover a new bivalent chromatin state in B. napus and suggest its key roles in regulating tissue-specific gene expression. Furthermore, we observe that different types of duplicated genes have differential patterns of histone modifications, DNA methylation, and selection pressures. Together, we provide valuable epigenetic data resources of allopolyploid B. napus and reveal the central role of epigenomic information in understanding transcriptional regulation in polyploid plants.