Project description:Transcriptional profiling of developing rice endosperm at seven days after flowering comparing aleurone layers with central starchy endosperm. Cereal productivity is dependent on the accumulation of storage compounds in the endosperm, a nutritive tissue that is composed of aleurone cells in the outermost regions and starchy endosperm in the inner region. The transcriptional analyses provides clues to the molecular basis for different metabolic pathways in response to the spatial and nutritional differences between rice aleurone cells and starchy endosperm. Two-condition experiment, Aleurone layers vs. central starchy endosperm. 3 biological replicates with color swap for each biological replicate
Project description:Transcriptional profiling of developing rice endosperm at seven days after flowering comparing aleurone layers with central starchy endosperm. Cereal productivity is dependent on the accumulation of storage compounds in the endosperm, a nutritive tissue that is composed of aleurone cells in the outermost regions and starchy endosperm in the inner region. The transcriptional analyses provides clues to the molecular basis for different metabolic pathways in response to the spatial and nutritional differences between rice aleurone cells and starchy endosperm.
Project description:The objective of the current study is to unravel the gene regulatory networks controlled by the nkd genes during maize endosperm development. We compared wild type (B73) vs. nkd mutant (introgressed into B73 background) transcriptomes in aleurone vs. starchy endosperm cell types captured by laser capture microdissection technology. We performed RNA seq analysis of mid-mature (15DAP) endosperm in two cell types [aleurone (A) and starchy endosperm (S)] of wild type B73 (B) and nkd mutant (N) kernels with three independent biological replicates.
Project description:The high molecular weight (HMW) subunits of wheat glutenin are synthesised only in the starchy endosperm tissue of the developing wheat grain. To place the differences observed between the endosperms of the transgenic and non-transgenic lines in a wider developmental context, the transcriptomes of endosperm at 14 dpa and leaf at 8 dpg of the transgenic line B102,1-1 were also compared.The experiment was performed with three biological replicates and hybridisations were performed in reverse dye labelling.
Project description:Transcriptome of starchy endosperm of hexaploid wheat var. Cadenza at 5 stages during grain-fill. This provides a reference set of all genes which are expressed in this single cell type during development which is of huge importance for human nutrition and for industrial uses of wheat grain. Here we focus on genes in glycosyl transferase and glycosyl hydrolase families which are responsible for the non-starch polysaccharide composition of wheat flour.
Project description:Starchy endosperm proteins determine wheat quality and exhibit, besides a quantitative protein gradient, a qualitative protein gradient from the outer to inner starchy endosperm. The goal was to investigate the relative differences in protein composition between the aleurone, sub-aleurone and inner endosperm. Using laser microdissection followed by nanoLC-MS/MS, an innovative method combining a high spatial specificity and analytical selectivity in sample-limited situations, 780 proteins were detected and classified by function. Relatively more gluten proteins were detected in the sub-aleurone compared to inner endosperm. Gluten composition-wise, the sub-aleurone is relatively more enriched in ω-gliadins, but impoverished in LMW-GS and γ-gliadins. While a basic set of albumins and globulins is detected across the entire endosperm, some proteins, like puroindoline-B, display an increasing (or decreasing) gradient. Histological origin and relative positioning of the endosperm cells are hypothesized to drive the protein gradient. Knowledge on this gradient provides major opportunities for the wheat manufacturing industry.
Project description:Grain development is a key life cycle stage of many plants. The development of seeds is the basis of agriculture and the primary source of calories consumed by humans. Here, we employ laser micro dissection (LMD) combined with shotgun proteomics to generate a cell-type proteome atlas of developing wheat endosperm at the early and late grain filling stages. We identified 1803 proteins from four different cell layers (aleurone (AL), sub-aleurone (SA), starchy endosperm (SE), and endosperm transfer cells (ETCs)) of developing endosperm at 15 Days after anthesis (DAA) and 26 DAA. Sixty-seven differentially expressed proteins in the aleurone, 31 in the sub-aleurone, 27 in the starchy endosperm, and 50 in the endosperm transfer cells were detected between these two-time points. The results revealed highly distinguishable proteome dynamics in the different cell layers of endosperm over the time course. We observed high general metabolic activity of the grain with regard to carbohydrate metabolism, defence against oxidative stress, and signalling in the different cell layers during the grain filling process. Cell-specific identification of SUT and GLUT transporters suggest a grain filling model via nucellar projections and endosperm transfer cells (ETCs) initiating starch biosynthesis in the starchy endosperm (SE). The identification and regulation dynamics of proteins in the different cell layers demonstrate a functional switch of the proteome from the early to the late grain filling stage. Based on these data, we proposed a model for sugar loading and starch biosynthesis in wheat developing endosperm, including an abundance switch of cell-type-specific key proteins.
Project description:Grain development in the Poaceae defines important end-use properties such as yield, quality and nutritive value. Microarray analyses have been performed on barley grain endosperm extracts from three to eight days after pollination (DAP), when cellularization of the syncytium occurs through the growth of cell walls around individual nuclei. Profiling of transcripts differentially expressed over time reveal 56 specific modules of genes that cluster into 15 groups. Expression patterns have been superimposed upon microscopy data, which identify the timing of key stages in grain development. Thus, cellularization is complete at six DAP, aleurone-related genes can be detected at seven to eight DAP, and starch synthase and hordein genes increase dramatically at seven and eight DAP, respectively. Genes known to be involved in cell wall metabolism are found predominantly in a single module, but analysis using a gene ontology approach splits these genes into four modules, which remain in a single cluster. Transcript levels of the cell wall-related genes peak at seven DAP and the developmental patterns of genes involved in arabinoxylan and (1,3;1,4)-β-glucan synthesis are defined. The transcript data are publicly available (www.etc.) and can be used to interrogate co-expression and differential expression patterns for other groups of genes. In addition, the examination of transcription factor genes that are co-expressed in modules of genes involved in specific processes, such as aleurone differentiation, can be used to identify candidate genes for the control of those particular processes during barley grain development.
Project description:This reports the transcript profiling of the aleurone and starchy endosperm layers of wheat seed over 3 time points critical in the development of the aleurone layer. Wheat is a critical food source globally. The aleurone layer develops from the starchy endosperm and is a concentrated source of vitamins and minerals, essential for the germination of the plant embryo. However the molecular mechanisms behind the development of this layer remain poorly understood. Here we present the first direct systematic comparison of the transcriptomes of the aleurone and starchy endosperm tissues of the wheat seed (Triticum aestivum) at time points critical to the development of the aleurone layer of 6, 9 and 14 days post anthesis. Gene expression patterns reflect the changing role of these tissues in seed development. Illumina sequencing gave 25 to 55 million sequence reads per tissue, of the trimmed reads, 70 – 81% mapped to reference expressed sequence transcripts. To quantify transcript abundance, RNA-Seq normalisation was performed to generate RPKM values, these were used in comparative analyses between the tissues at each time point using Kals Z-test. Sequences with significantly different RPKM values were categorised on the basis of tissue and time point expression and functionally annotated using standardised gene ontology vocabularies, revealing two very distinct tissues. In conclusion we show the relationships between and the fundamental biological reprogramming of the two major biologically and economically significant tissues of the wheat seed over time. Understanding these changes in gene expression profiles is essential to mining the potential these tissues hold for human nutrition and contributing to foundational and systems biology of this important crop.