Project description:To obtain better insight into the underlying mechanism of melatonin in switchgrass growth, flowering and defence, we performed proteomics analyses between transgenic lines overexpressing melatonin biosynthesis genes and transgenic control (expressing only the empty vector) plants.
Project description:Soil-borne microbes can establish compatible relationships with host plants, providing a large variety of nutritive and protective compounds in exchange for photosynthesized sugars. However, the molecular mechanisms mediating the establishment of these beneficial relationships remain unclear. Our previous genetic mapping and whole-genome resequencing studies identified a gene deletion event of a Populus trichocarpa lectin receptor-like kinase gene PtLecRLK1 in Populus deltoides that was associated with poor root colonization by the ectomycorrhizal fungus Laccaria bicolor. By introducing PtLecRLK1 into a perennial grass known to be a non-host of L. bicolor, switchgrass (Panicum virgatum L.), we found that L. bicolor colonizes ZmUbipro-PtLecRLK1 transgenic switchgrass roots, which illustrates that the introduction of PtLecRLK1 has the potential to convert a non-host to a host of L. bicolor. Furthermore, transcriptomic and proteomic analyses on inoculated transgenic switchgrass roots revealed genes/proteins overrepresented in the compatible interaction and underrepresented in the pathogenic defense pathway, consistent with the view that pathogenic defense response is downregulated during compatible interaction. Metabolomic profiling revealed that root colonization in the transgenic switchgrass was associated with an increase in N-containing metabolites and a decrease in organic acids, sugars, and aromatic hydroxycinnamate conjugates, which are often seen in the early steps of establishing compatible interactions. These studies illustrate that PtLecRLK1 is able to render a plant susceptible to colonization by the ectomycorrhizal fungus L. bicolor and shed light on engineering mycorrhizal symbiosis into a non-host to enhance plant productivity and fitness on marginal lands.
Project description:The combined heat and drought stress influence the plant growth and development. Switchgrass is an economically important crop due to the availability of high biomass with little water and nutrient requirements. Earlier reports suggested that switchgrass growth and yield highly influenced by heat and drought. The mechanism behind heat and drought stress is not fully understood in switchgrass. This study has undertaken to analyze the epigenetic modification using ChIP-Seq analysis with the activation histone mark H3K4me3. Conclusion: Our study provides the first epigenomic analysis of heat and drought response in switchgrass. This comprehensive resource will provide other epigenomic regulated information in non-model plant species.
Project description:Purpose: Increasing biomass yield and quality of feedstock have been a recent interest in switchgrass research. Despite the economic importance of switchgrass, increasing temperature and water deficit are limiting factors to the cultivation of bioenergy crops in the semi-arid areas. The effect of individual drought or heat stress has been studied separately in switchgrass. However, there is relatively limited or no report on the molecular basis of combined abiotic stress tolerance in switchgrass particularly the combination of drought and heat stress. We used RNA-Seq approaches to elucidate the transcriptome changes of switchgrass in response to drought and high temperatures simultaneously. Method: We conducted solely drought treatment in switchgrass plant Alamo AP13 by withholding water after 45 days of growing. For the combination of drought and heat effect, heat treatment (35 °C/25 °C day/night) was imposed after 72 h of the initiation of drought. Samples were collected at 0 h, 72 h, 96 h, 120 h, 144 h, and 168 h after treatment imposition, total RNA was extracted, and RNA-Seq conducted. Results:Out of total 32,190 genes, we identified 3,912, as DT responsive genes, 2,339 and 4,635 as , heat (HT) and drought and heat (DTHT) responsive genes, respectively. There were 209, 106, and 220 transcription factors (TFs) differentially expressed under DT, HT and DTHT respectively Conclusion: Through RNA-Seq analysis, we have identified unique and overlapping genes in response to DT and combined DTHT stress in switchgrass. The combination of DT and HT stress may affect the photosynthetic machinery and phenylpropanoid pathway of switchgrass which negatively impacts lignin synthesis and biomass production of switchgrass. The biological function of genes identified particularly in response to DTHT stress could further be confirmed by techniques such as single point mutation or RNAi.
2022-03-31 | GSE174278 | GEO
Project description:RNA-seq analysis of transgenic switchgrass
Project description:Clonal QSuB switchgrass plants (3 independent transformation events), and their corresponding wild type (var Alamo), grown in a growth chamber and the field, were harvested at two time points (five replicates) during the growing season across two years (2018, 2019), to compare the effects of environment on genetically identical engineered plants. To complement this, we used QsuB plus wild type for Arabidopsis grown in a walk in growth chamber. Three replicates of tissue will be harvested at a single time point. Plants will be well-watered or drought stressed.
The work (proposal:https://doi.org/10.46936/10.25585/60000997) conducted by the U.S. Department of Energy Joint Genome Institute (https://ror.org/04xm1d337), a DOE Office of Science User Facility, is supported by the Office of Science of the U.S. Department of Energy operated under Contract No. DE-AC02-05CH11231.
Project description:Soil-borne microbes can establish compatible relationships with host plants, providing a large variety of nutritive and protective compounds in exchange for photosynthesized sugars. However, the molecular signals mediating the establishment of these beneficial relationships remain unclear. Our previous genetic mapping and whole-genome resequencing studies identified a gene deletion event of a Populus trichocarpa lectin receptor-like kinase gene PtLecRLK1 in Populus deltoides that was associated with poor root colonization by the ectomycorrhizal fungus Laccaria bicolor. By introducing PtLecRLK1 into a perennial grass known to be a non-host of L. bicolor, switchgrass (Panicum virgatum L.), we found that the L. bicolor colonizes the ZmUbipro-PtLecRLK1 transgenic switchgrass roots which illustrates that introduction of PtLecRLK1 has the potential to convert a non-host to a host of L. bicolor. Further transcriptomic and proteomic analyses on inoculated transgenic switchgrass root samples revealed genes/proteins overrepresented in the compatible interaction and underrepresented in the pathogenic defense pathway, consistent with the view that pathogenic defense response is downregulated during compatible interaction. Metabolomic profiling revealed that root colonization in the transgenic switchgrass was associated with an increase in N-containing metabolites and a decrease in organic acids, sugars, and phenolics-like hydroxycinnamate conjugates, which are often seen in the early steps of establishing compatible interactions in compatible partners. This work illustrates that PtLecRLK1 is able to render a plant susceptible to colonization by the ectomycorrhizal fungus L. bicolor and sheds light on engineering mycorrhizal symbiosis into a non-host to enhance plant productivity and fitness in marginal lands.