Project description:Small RNAs are common and effective modulators of gene expression in eukaryotic organisms. To characterize the small RNAs expressed during rice seed development, massively parallel signature sequencing (MPSS) was performed, resulting in the obtainment of 22-nt sequence signatures. Through integrative analysis,novel miRNAs were identified mostly based on the miRNA* accumulation.
Project description:Small RNAs are common and effective modulators of gene expression in eukaryotic organisms. To characterize the small RNAs expressed during rice seed development, massively parallel signature sequencing (MPSS) was performed, resulting in the obtainment of 22-nt sequence signatures. Through integrative analysis,novel miRNAs were identified mostly based on the miRNA* accumulation. Total RNA was isolated separately from rice seeds collected at 3, 6, 9 and 12 days after anthesis (DAA), then mixed into a library and separated on denatured polyacrylamide gel electrophoresis (PAGE). The fraction of 18-26 nt small RNA was recovered by small RNA gel extraction Kit.
Project description:Seed germination is a complicated physiological process, during which structures of mitochondria and plastids are recovered, and metabolisms are re-activated (Han and Yang, 2015). It has been shown that metabolism reactivation is very important for rice germination (He et al., 2011b;Han et al., 2014a). It is still unknown if protein acetylation involved in and regulate these metabolisms during rice seed germination. To answer this question, we globally profiled the acetylome in rice embryos from the germinating seeds. A number of acetylated enzymes were identified. The results provide more information about the metabolism regulation in germinating seeds.
Project description:affy_rice_2012_01 - ivt - One of the key questions for future agriculture will be to save agronomical relevant biodiversity. To do so, it is important to select the best crop cultivars that will germinate efficiently (good seed vigor) and for a long period of time (good seed longevity). Surprisingly, while mankind rely heavily on cereals, very few studies have identified genes positively related to cereal seed vigor and longevity. To close this scientific gap, we aimed to identify genes positively involved in rice seed vigor and longevity. We thus used a “controlled deterioration treatment (Tesnier et al., 2002) to mimic natural seed ageing. Seeds are first equilibrated at 25°C and 85% relative hygrometry during three days. Then, during 15 days, three different batch of seeds are either (i) kept at 25°C and 85% RH (control seeds), (ii) placed at 40°C and 85% RH (loss of seed vigor) or (iii) placed at 45°C and 85% RH (loss of germination capacity). Finally, seeds are equilibrated at 25°C and 32% RH during three days. Using this CDT treatment, we obtained rice seeds with contrasted seed vigor or germination capacity. We extracted the total RNA from the embryos and we analysed their transcriptome using the Affymetrix Rice Genome Array.-We applied a Controlled Deterioration Treatment (CDT) to seeds from the reference rice cultivar Nipponbare. First, all seeds are equilibrated at 25°C and 85% relative hygrometry. Then, depending on the treatment, seeds are placed at 25, 40 or 45°C in 85% relative hygrometry before being finally equilibrated at 25°C and 32% relative hygrometry. The germination of the three seed batches was measured during five days with one measure every 8h. Seeds placed at 25°C during the whole experiment were similar to control seeds kept in the fridge and germinated at nearly 100% in 48h. Seeds placed at 40°C during 15 days germinate at 74% but show altered seedling phenotypes (loss of seed vigor). Finally, seeds placed at 45°C do not germinate.
Project description:affy_rice_2012_01 - ovation - One of the key questions for future agriculture will be to save agronomical relevant biodiversity. To do so, it is important to select the best crop cultivars that will germinate efficiently (good seed vigor) and for a long period of time (good seed longevity). Surprisingly, while mankind rely heavily on cereals, very few studies have identified genes positively related to cereal seed vigor and longevity. To close this scientific gap, we aimed to identify genes positively involved in rice seed vigor and longevity. We thus used a “controlled deterioration treatment (Tesnier et al., 2002) to mimic natural seed ageing. Seeds are first equilibrated at 25°C and 85% relative hygrometry during three days. Then, during 15 days, three different batch of seeds are either (i) kept at 25°C and 85% RH (control seeds), (ii) placed at 40°C and 85% RH (loss of seed vigor) or (iii) placed at 45°C and 85% RH (loss of germination capacity). Finally, seeds are equilibrated at 25°C and 32% RH during three days. Using this CDT treatment, we obtained rice seeds with contrasted seed vigor or germination capacity. We extracted the total RNA from the embryos and we analysed their transcriptome using the Affymetrix Rice Genome Array.-We applied a Controlled Deterioration Treatment (CDT) to seeds from the reference rice cultivar Nipponbare. First, all seeds are equilibrated at 25°C and 85% relative hygrometry. Then, depending on the treatment, seeds are placed at 25, 40 or 45°C in 85% relative hygrometry before being finally equilibrated at 25°C and 32% relative hygrometry. The germination of the three seed batches was measured during five days with one measure every 8h. Seeds placed at 25°C during the whole experiment were similar to control seeds kept in the fridge and germinated at nearly 100% in 48h. Seeds placed at 40°C during 15 days germinate at 74% but show altered seedling phenotypes (loss of seed vigor). Finally, seeds placed at 45°C do not germinate.
Project description:In this study, we sequenced the sRNAs population from embryos of 0, 12, and 24 HAI rice seeds using next-generation deep sequencing technology. A series of miRNAs were identified, including both known and novel miRNAs. We also predicted the potential targets for the miRNAs. RT-PCR and 5’ RACE assay were performed to confirm some deep sequencing and target prediction results. This study provides the unique composition and expressional profiles of miRNAs and their potential regulations in the embryo at the early stages of rice seed germination.
Project description:affy_rice_2011_03 - affy_compartimentation_rice_albumen_embryon - During germination, the rice seed goes from a dry quiescent state to an active metabolism. As with all cereals, the rice seed is highly differentiated between the embryo (that will give rise to the future plantlet) and the endosperm (that contains the seed storage compounds and that will degenerate). The molecular mechanisms operating in the rice seed embryo have begun to be described. Yet, very few studies have focused specifically on the endosperm during the germination process. In particular, the endosperm is mostly addressed with regards to its storage proteins but we have detected a large protein diversity by two-dimensional electrophoresis. Similarly, the endosperm is rich in total RNA which suggest that gene expression coming from seed maturation could play a role during the germination process. In this context, we want to compare the transcriptome of the embryo and the endosperm during rice seed germination. -We germinate rice seeds of the first sequenced rice cultivar i.e. Nipponbare during 0, 4, 8, 12, 16 and 24h of imbibition in sterile distilled water. Germination occurs under constant air bubbling, in the dark at 30°C. These rice seeds are then manually dissected into embryo and endosperm fractions. -The embryo-derived samples are abbreviated in “E” while the endosperm samples are abbreviated “A”. The germination time-point is indicated after the letter (e.g. E8 for embryo samples harvested after 8 hours of germination). Finally, the biological repetition number is indicated before the letter and the time digit (e.g. 1-E8 for an embryo sample from the first repetition at 8 hours of imbibition).
Project description:affy_rice_2012_01 - ovation - One of the key questions for future agriculture will be to save agronomical relevant biodiversity. To do so, it is important to select the best crop cultivars that will germinate efficiently (good seed vigor) and for a long period of time (good seed longevity). Surprisingly, while mankind rely heavily on cereals, very few studies have identified genes positively related to cereal seed vigor and longevity. To close this scientific gap, we aimed to identify genes positively involved in rice seed vigor and longevity. We thus used a “controlled deterioration treatment (Tesnier et al., 2002) to mimic natural seed ageing. Seeds are first equilibrated at 25°C and 85% relative hygrometry during three days. Then, during 15 days, three different batch of seeds are either (i) kept at 25°C and 85% RH (control seeds), (ii) placed at 40°C and 85% RH (loss of seed vigor) or (iii) placed at 45°C and 85% RH (loss of germination capacity). Finally, seeds are equilibrated at 25°C and 32% RH during three days. Using this CDT treatment, we obtained rice seeds with contrasted seed vigor or germination capacity. We extracted the total RNA from the embryos and we analysed their transcriptome using the Affymetrix Rice Genome Array.-We applied a Controlled Deterioration Treatment (CDT) to seeds from the reference rice cultivar Nipponbare. First, all seeds are equilibrated at 25°C and 85% relative hygrometry. Then, depending on the treatment, seeds are placed at 25, 40 or 45°C in 85% relative hygrometry before being finally equilibrated at 25°C and 32% relative hygrometry. The germination of the three seed batches was measured during five days with one measure every 8h. Seeds placed at 25°C during the whole experiment were similar to control seeds kept in the fridge and germinated at nearly 100% in 48h. Seeds placed at 40°C during 15 days germinate at 74% but show altered seedling phenotypes (loss of seed vigor). Finally, seeds placed at 45°C do not germinate. 6 arrays - rice; treated vs untreated comparison