Project description:The phytohormone gibberellic acid (GA) is well known to promote seed germination in plants. One of its functions is to stimulate the production of hydrolytic enzymes in the aleurone and their secretion to the adjacent endosperm. The storage in the endosperm is thus degraded by these hydrolases into small molecules, which are utilized as nutrients for embryo growth to establish the young seedling. ABA in contrast plays antagonistic role to GA to keep seed in dormancy. Cereal aleurone has been established as a model system to investigate giberrellin (GA) and abscisic acid (ABA) responses. Using Barley 1 GeneChip, we examined the mRNA accumulation of over 22 000 genes in barley aleurone treated with GA, ABA, GA plus ABA, and sln1 mutant. Barley aleurone tissues were separated from half-seed without embryo. Three independent RNA samples for each treatment including the control without any hormone were extracted and hybridized onto Affymetrix microarrays. We also did microarray in three replications for sln1 mutant aleurone without hormone treatment.
Project description:The phytohormone gibberellic acid (GA) is well known to promote seed germination in plants. One of its functions is to stimulate the production of hydrolytic enzymes in the aleurone and their secretion to the adjacent endosperm. The storage in the endosperm is thus degraded by these hydrolases into small molecules, which are utilized as nutrients for embryo growth to establish the young seedling. ABA in contrast plays antagonistic role to GA to keep seed in dormancy. Cereal aleurone has been established as a model system to investigate giberrellin (GA) and abscisic acid (ABA) responses. Using Barley 1 GeneChip, we examined the mRNA accumulation of over 22 000 genes in barley aleurone treated with GA, ABA, GA plus ABA, and sln1 mutant.
Project description:Plant seeds prepare for germination already during seed maturation. We performed a detailed transcriptome analysis of barley grain maturation, desiccation and germination in two tissue fractions (endosperm/aleurone = e/a and embryo = em) using the Affymetrix barley1 chip. Keywords: time course
Project description:Plant seeds prepare for germination already during seed maturation. We performed a detailed transcriptome analysis of barley grain maturation, desiccation and germination in two tissue fractions (endosperm/aleurone = e/a and embryo = em) using the Affymetrix barley1 chip. Experiment Overall Design: Barley developing and germinating seeds were harvested at different time points after flowering (developing) and imbibition (germinating). To further disseect the influence of different tissues, seeds were dissecte and tissues were analyzed individually.
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:Hordeum vulgare (barley) hordoindolines (HINs), HINa, HINb1 and HINb2, are orthologous proteins of wheat puroindolines (PINs) that are small, basic, cysteine-rich seed-specific proteins and responsible for grain hardness. Grain hardness, is, next to its protein content, a major quality trait. In barley, HINb is most highly expressed in the mid-stage developed endosperm and is associated with both major endosperm texture and grain hardness. However, data required tounderstand the spatio-temporal dynamics of HIN transcripts and HIN protein regulation during grain filling processes are missing. Using reverse transcription quantitative PCR (RT-qPCR) and proteomics we analyzed HIN transcript and HIN protein abundance from whole seeds (WSs) at four ((6 days after pollination (dap), 10 dap, 12 dap and ≥ 20 dap)) as well as from aleurone, subaleurone and starchy endosperm at two (12 dap and ≥ 20 dap) developmental stages. At the WS level, results from RT-qPCR, proteomics and western blot showed a continuous increase of HIN transcript and HIN protein abundance across these four developmental stages. Miroscopic studies revealed HIN localization mainly at the vacuolar membrane in the aleurone, at protein bodies (PBs) in subaleurone and at the periphery of starch granules in the starchy endosperm. Laser microdissetion (LMD) proteomic analyses identified HINb2 as the most prominent HIN protein in starchy endosperm at ≥ 20 dap. Additionally, our quantification data revealed a poor correlation between transcript and protein levels of HINs in subaleurone during development. Here, we correlated data achieved by RT-qPCR, proteomics and microscopy that reveal different expression and localization pattern of HINs in each layer during barley endosperm development. This indicats a contribution of each tissue to the regulation of HINs during grain filling. The effect of the high protein abundance of HINs in the starchy endosperm and their localization at the periphery of starch granules at late development stages at the high end-product quality is discussed. Understanding the spatio-temporal regulated HINs is essential to improve barley quality traits for high end-product quality, as hard texture of the barley grain is regulated by the ratio between HINb/HINa.
Project description:Microbiota from rats fed with wheat aleurone and plant omega fatty acids In this study we investigated how an AX-rich WA and ALA from linseed oil (LO) modulate the gut microbiota of rats. Wistar rats were fed a standard diet and received either an iso-energetic control oil (PO), control oil + aleurone (A+PO), linseed oil (LO) or linseed oil + aleurone (A+LO) during 12 weeks. Feacal samples were recovered after the 12 week treatments. DNA extractions were performed using using the Qiagen's DNA Stool Kit (Qiagen, West Sussex, UK). 10ng of DNA template were amplified by PCR (16S gene) and purified using Qiagen's Qiaquick PCR purification kit (Qiagen, West Sussex, UK). 1ug of purified PCR product were labelled with either Cy3 or Cy5 using Genomic DNA ULS Labelling kit (Agilent Technologies, Palo Alto, CA). 250ng of labelled DNA were hybridized on the microarray for 24h at 65M-BM-0C. Washings were performed as recommended by the manufacturer. Microarray scanning was performed on a Surescan Microarray scanner (Agilent Technologies, Palo Alto, CA). Data were extracted using the Feature extraction software (Agilent Technologies, Palo Alto, CA). The retained intensity value for each probe was the ratio between the spotM-bM-^@M-^Ys median intensity signals and the median of background signals. A 13 chip study was realized to analyze the feacal microbiota of rats treated with either an iso-energetic control oil (PO), control oil + aleurone (A+PO), linseed oil (LO) or linseed oil + aleurone (A+LO) during 12 weeks. Each microarray corresponding to hybridization with 250ng of labelled 16S rRNA gene amplicons from 2 rat DNA faecal samples. Microbiota structure and diversity were assessed using the HuGChip (Tottey et al., 2013). Each probe (4441) was synthetized in three replicates. On the same array, 2 different samples were hybridized. One labelled with the Cy3 dye and one with the Cy5 dye. The results were processed as single channel (13 raw data files available on Series records for 25 samples).
Project description:Microbiota from rats fed with wheat aleurone and plant omega fatty acids In this study we investigated how an AX-rich WA and ALA from linseed oil (LO) modulate the gut microbiota of rats. Wistar rats were fed a standard diet and received either an iso-energetic control oil (PO), control oil + aleurone (A+PO), linseed oil (LO) or linseed oil + aleurone (A+LO) during 12 weeks. Feacal samples were recovered after the 12 week treatments. DNA extractions were performed using using the Qiagen's DNA Stool Kit (Qiagen, West Sussex, UK). 10ng of DNA template were amplified by PCR (16S gene) and purified using Qiagen's Qiaquick PCR purification kit (Qiagen, West Sussex, UK). 1ug of purified PCR product were labelled with either Cy3 or Cy5 using Genomic DNA ULS Labelling kit (Agilent Technologies, Palo Alto, CA). 250ng of labelled DNA were hybridized on the microarray for 24h at 65°C. Washings were performed as recommended by the manufacturer. Microarray scanning was performed on a Surescan Microarray scanner (Agilent Technologies, Palo Alto, CA). Data were extracted using the Feature extraction software (Agilent Technologies, Palo Alto, CA). The retained intensity value for each probe was the ratio between the spot’s median intensity signals and the median of background signals.