Project description:The aims of our study were: 1) to elucidate physiological responses in three Miscanthus species and newly bred triploid hybrid in three water stress treatment conditions 2) utilise the induced physiological conditions for an in-depth transcriptome study on the molecular basis of water stress in Miscanthus spp.
Project description:Cymbopogon spp. are grass species widely used around the world as medicinal plants and in various industries for the production of perfumes and pharmaceuticals. Despite their extensive use, there are relatively few studies at the genomic and transcriptomic levels. In this study, transcriptomic data were generated for two species—Cymbopogon flexuosus and Cymbopogon winterianus—to investigate evolutionary aspects and the expression of genes associated with secondary metabolite biosynthesis. The transcriptome assembly revealed a total of 18,286 and 22,458 transcripts for C. flexuosus and C. winterianus, respectively. Furthermore, the reads were mapped against the genomes of related species, including Andropogon gerardii, Sorghum bicolor, Saccharum officinarum, Miscanthus sinensis, Miscanthus lutarioriparius, and Zea mays, to assess their conservation across these genomes. The results indicated which species are more closely related to the Cymbopogon genus and highlighted key differences in metabolic pathways.
Project description:The genome sizes of five Miscanthus species, including 79 accessions of M. lutarioriparius, 8 of M. floridulus, 6 of M. sacchariflorus, 7 of M. sinensis, and 4 of M. × giganteus were examined using flow cytometry. The overall average nuclear DNA content were 4.256 ± 0.6 pg/2C in M. lutarioriparius, 5.175 ± 0.3 pg/2C in M. floridulus, 3.956 ± 0.2 pg/2C in M. sacchariflorus, 5.272 ± 0.2 pg/2C in M. sinensis, and 6.932 ± 0.1 pg/2C in M. × giganteus. Interspecific variation was found at the diploid level, suggesting that DNA content might be a parameter that can be used to differentiate the species. Tetraploid populations were found in M. lutarioriparius, M. sacchariflorus, and M. sinensis, and their DNA content were 8.34 ± 1.2, 8.52, and 8.355 pg, respectively. The association between the DNA content of M. lutarioriparius, collected from representative ranges across the Yangtze River, and its geographic distribution was statistically analyzed. A consistent pattern of DNA content variation in 79 M. lutarioriparius accessions across its entire geographic range was found in this study. Along the Yangtze River, the DNA content of M. lutarioriparius tended to increase from the upstream to the downstream areas, and almost all tetraploids gathered in the upstream area extended to coastal regions.
Project description:Small RNAs (21-24 nt) are pivotal regulators of gene expression that guide both transcriptional and post-transcriptional silencing mechanisms in diverse eukaryotes, including most if not all plants. MicroRNAs (miRNAs) and short interfering RNAs (siRNAs) are the two major types, both of which have a demonstrated and important role in plant development, stress responses and pathogen resistance. In this work, we used a deep sequencing approach (Sequencing-By-Synthesis, or SBS) to develop sequence resources of small RNAs from different Miscanthus x giganteus tissues (including leaves, flowers, and rhizomes). The high depth of the resulting datasets enabled us to examine in detail critical small RNA features such as size distribution, tissue-specific regulation and sequence conservation between different organs in this species. We also developed database resources and a dedicated website (http://smallrna.udel.edu/) with computational tools for allowing other users to identify new miRNAs or siRNAs involved in specific regulatory pathways, verify the degree of conservation of these sequences in other plant species and map small RNAs on genes or larger regions of the genome under study.