Project description:Polyploidy has played an extensive role in the evolution of flowering plants. Allopolyploids, with subgenomes containing duplicated gene pairs called homeologs, can show rapid transcriptome changes including novel alternative splicing (AS) patterns. The extent to which abiotic stress modulates AS of homeologs is a nascent topic in polyploidy research. We subjected both natural and resynthesized lines of polyploid Brassica napus, along with the progenitors B. rapa and B. oleracea, to infection with the fungal pathogen Sclerotinia sclerotiorum. RNA-seq analyses revealed widespread divergence between polyploid subgenomes in both gene expression and AS patterns. Resynthesized B. napus displayed significantly more A and C subgenome biased homeologs under pathogen infection than during uninfected growth. Differential AS (DAS) in response to infection was highest in natural B. napus (12,709 DAS events) and lower in resynthesized Brassica napus (8,863 DAS events). Natural B. napus had more up-regulated events and fewer down-regulated events. There was a global expression bias towards the B. oleracea-derived (C) subgenome in both resynthesized and natural B. napus, enhanced by widespread non-parental downregulation of the B. rapa-derived (A) homeolog. In the resynthesized B. napus specifically, this resulted a disproportionate C subgenome contribution to pathogen defense response, characterized by biases in both transcript expression levels and the proportion of induced genes. Our results elucidate the complex ways in which Sclerotinia infection affects expression and AS of homeologous genes in natural and resynthesized B. napus, and indicate that abiotic stress can influence the evolution of homeologous genes in polyploids.
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:Analysis of the different gene expression profiles of natural and resynthesized Brassica polyploids with Illumina deep sequencing technology could help to improve our knowledge of polyploid genome evolution. We obtained approximately 6 million sequence tags per sample,and 6018254, 5930726, 6022170, 5950123, 5991210, 5798939, 5823113, 5772449,5858527 and 5657697 clean tags were obtained in libraries of B. rapa, B. oleracea, B. napus-F1, B. napus-F2, B. napus-F3, B. napus-F4, natural B. napus, B. nigra, B. juncea and B. carinata, respectively.16574, 15970, 22059, 18155, 16479, 18196, 17448, 13867, 19424 and 16645 genes of B. rapa genome were unambigously mapped by sequence tags of these ten DGE libraries, respectively. Differentially expressed genes during polyploidization were broadly discovered by comparing the tetraploids with their progenitors. mRNA obtained from young leaves of 28-days-old seedlings were compared during polyploidization.
Project description:Analysis of the different gene expression profiles of natural and resynthesized Brassica polyploids with Illumina deep sequencing technology could help to improve our knowledge of polyploid genome evolution. We obtained approximately 6 million sequence tags per sample,and 6018254, 5930726, 6022170, 5950123, 5991210, 5798939, 5823113, 5772449,5858527 and 5657697 clean tags were obtained in libraries of B. rapa, B. oleracea, B. napus-F1, B. napus-F2, B. napus-F3, B. napus-F4, natural B. napus, B. nigra, B. juncea and B. carinata, respectively.16574, 15970, 22059, 18155, 16479, 18196, 17448, 13867, 19424 and 16645 genes of B. rapa genome were unambigously mapped by sequence tags of these ten DGE libraries, respectively. Differentially expressed genes during polyploidization were broadly discovered by comparing the tetraploids with their progenitors.
Project description:Changes to gene expression and splicing are investigated between parental species (B. oleracea and B. rapa) and three resynthesized allopolyploids, as well as a natural B. napus
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:Time course of gene expression profiles during seed development and maturation in Brassica napus were studied using Combimatrix Brassica microarray.
Project description:Time course of gene expression profiles during seed development and maturation in Brassica napus were studied using Combimatrix Brassica microarray. The time course expression of 90K Brassica napus EST contigs were measured at 8 developing seed stages of 10, 15, 20, 25, 30, 35, 40 and 45 DAF (days after flowering) using single color microarray