Project description:Apple seeds were subjected to accelerated aging. After 7, 14, and 21 days of aging, embryos were isolated. Part of the embryos were shortly fumigated with nitric oxide (NO). After 48 h of embryos culture (aged embryos or aged embryos treated with NO), embryonic axes were used to extract the total RNA. RT-qPCR were done to analyze the changes in the expression of genes related to seed aging. Short-term (3 h) treatment of embryos isolated from accelerated aged apple seeds (Malus domestica Borkh.) with NO partially reduced the effects of aging. The aim of the study was to investigate the impact of the short-term NO treatment of embryos isolated from apple seeds subjected to accelerated aging on the expression of genes potentially linked to the regulation of seed aging. Apple seeds were artificially aged for 7, 14, or 21 days. Then the embryos were isolated from the seeds, treated with NO, and cultured for 48 h. Progression of seeds aging was associated with the decreased transcript levels of most of the analyzed genes (Lea1, Lea2a, Lea4, Hsp70b, Hsp20a, Hsp20b, ClpB1, ClpB4, Cpn60a, Cpn60b, Raptor, and Saur). The role of NO in the mitigation of seed aging depended on the duration of the aging. After 7 and 14 days of seed aging, a decreased expression of genes potentially associated with the promotion of aging (Tor, Raptor, Saur) was noted. NO-dependent regulation of seed aging was associated with the stimulation of the expression of genes encoding chaperones and proteins involved in the repair of damaged proteins. After NO application, the greatest upregulation of ClpB, Pimt was noted in the embryos isolated from seeds subjected to 7-day long accelerated aging, Hsp70b, Hsp70c, Cpn in the embryos of seeds aged for 14 days, and Lea2a in the embryos of seeds after 21 days of aging.
Project description:This Project investigates the impact of elevated temperatures and relative humidity on the aging process of chia seeds (Salvia hispanica L.). The study employs proteomics to examine molecular responses to accelerated aging in two chia genotypes. The results underscore the importance of evaluating changes in proteins of aged seeds to gain insights into the biological mechanisms responsible for maintaining chia seed integrity during the aging process.
Project description:As a species mostly planted in tropical and subtropical regions, rice is sensitive to chilling temperature, especially at reproductive stage. However, the effect of low temperature on seed development has not been well characterized. The transcriptome of two rice cultivars Zhonghua11 and Hanfeng were analyzed to characterize the gene regulatory networks of rice seed during low temperature treatment.
Project description:We designed an array based on the release 7 of Michigan State University (MSU) rice genome annotation database (http://rice.plantbiology.msu.edu). The array was used for investigating the expression divergence and regulation between two contrasting rice genotypes under high salinity stress. The expression analysis was carried out using 14-day old whole seedlings from both japonica and indica rice lines. Two samples from NaCl treatment (0h and 8h) for each line were collected for the analysis. Two biological replicates were carried out for both control and NaCl treatments, resulting in a dataset of 8 microarrays.
Project description:Seed longevity is a crucial trait in agriculture as it determines the ability of seeds to maintain viability during dry storage. However, the molecular mechanism underlying seed aging and reduced seed longevity are currently not well understood. Here we report the comparative proteome and metabolome profiling of three rice cultivars varying in aging tolerance including an aging tolerant indica cultivar Dharial, an aging sensitive japonica cultivar Ilmi, and a moderately aging tolerant cultivar A2 that was generated by crossing between Dharial and Ilmi. Results obtained from comparative proteome and metabolome profiling suggest that aged seeds of all the cultivars utilize ubiquitin proteasome-mediated protein degradation which results in the accumulation of free amino acids in Ilmi while tolerant cultivars utilize those for energy production and synthesis of heat shock proteins, especially hsp20/alpha crystallin family protein. Additionally, aging tolerant cultivar seems to activate brassinosteroid signalling and suppress jasmonate signaling to initiate a signaling cascade that allows efficient detoxification of aging induced ROS to maintain the seed longevity during aging. Taken together, these results provide an in-depth understand of aging induced changes in rice seeds.
Project description:As a species mostly planted in tropical and subtropical regions, rice is sensitive to chilling temperature, especially at reproductive stage. However, the effect of low temperature on seed development has not been well characterized. The transcriptome of two rice cultivars Zhonghua11 and Hanfeng were analyzed to characterize the gene regulatory networks of rice seed during low temperature treatment. Whole plants of two rice cultivars Zhonghua11 (low temperature sensitive) and Hanfeng (low temperature tolerance) were treated at 14°C for 2 days during seed development stage. The plants without treatment serve as controls. Rice seeds were harvested for RNA extraction.
Project description:Purpose: The goal of our study is to compare two different ecotypes of Oryza sativa L., PHS-susceptible rice trait and PHS-resistant rice trait under three different maturation stages in rice seed embryo with profile of miRNA-seq. Methods: Oryza sativa. L miRNA profiles of two different ecotypes with 3 different maturation stages of rice seed embryo were generated by NGS, in duplicate, following Illumina NGS workflow. Results: We found the differentially expressed microRNAs between PHS-susceptible rice trait and PHS-resistant rice trait according to the three different seed maturation stages. Target transcripts of differentially expressed microRNAs have been predicted via psRNATarget web server, and a part of those target genes are likely to be regulated by microRNAs, affecting overall responses to heat stress and the regulation of seed dormancy during maturation. Conclusions: Our study represents the analysis of rice seed small RNAs, specifically microRNAs, under two different ecotypes, three different seed maturation stages in rice seed embryo. Our results show that microRNAs are involved in response to heat stress and the regulation of seed dormancy. This study will provide a foundation for understanding dynamics of seed dormancy during the seed development and overcoming pre-harvest sprouting.
Project description:A submergence tolerant indica rice cultivar FR13A, was also reported to withstand salt stress and proven in our experiments. The mechanism of tolerance is yet to be studied by forward genetics approach. However, it is known that salt stress tolerance is governed by several QTLs and not by a single gene. To understand the mechanism of such a complex mechanism of salt tolerance we selected, two indica rice genotypes namely, I) FR13A, a tolerant indica variety and ii) IR24, a susceptible genotype for this study. We used the 22K rice Oligoarray from Agilent technologies to study the transcript profile in the leaves of the two contrasting rice genotypes under constitutive and salt stress conditions at seedling stage. Experiment Overall Design: We used Agilent rice gene chips (G4138A) to investigate the transcript level changes in rice plant tissues during salt stress treatment. We used two contrasting rice genotypes (FR13A tolerant and IR24 susceptible) differing in salt stress response. Plants were grown in growth chambers and treated with 150 mM salt concentration at 14th DAS. Sampling was done in both constitutive and treated plants at 3 time points. Two replications of microarray experiments were carried out by hybridizing the RNA from tolerant samples against the susceptible lines on the same slide.
Project description:The current knowledge of drought stress transcriptomes in rice are mostly relying on comparative studies of diverse genetic background under drought. A more reliable approach is to use near-isogenic lines (NILs) with a common genetic background (Donar parent: Aday Sel, Recurrent parent: IR64), but contrasting levels of resistance to drought stress under initial exposure to water deficit. Here, we examined two pairs of NILs in IR64 background with contrasting drought tolerance. We obtained gene expression profile in roots of rice NILs under different levels of drought stress help to identify genes and mechanisms involved in drought stress.