Project description:Camelina is an annual oilseed plant that is gaining momentum as a biofuel winter cover crop. Understanding gene regulatory networks (GRNs) is essential to deciphering plant metabolic pathways, including lipid metabolism. Here, we take advantage of a growing collection of gene expression datasets to predict transcription factors (TFs) associated with the control of Camelina lipid metabolism. Also, we performed RNA-seq assays of Camelina's seed at 5, 8, and 11 days post-anthesis (DPA) to improve the transcriptomic resolution of the early stages of the Camelina seed development. We identified ~350 TFs highly co-expressed with lipid-related genes (LRGs). After prioritizing the top 22 TFs for further validation, we identified DNA-binding sites and predicted target genes for 16/22 TF using DNA affinity purification sequencing (DAP-seq). Enrichment analyses supported the co-expression prediction for most TF candidates, and the comparison to Arabidopsis revealed some common themes and aspects unique to Camelina. Altogether, the integration of co-expression data and DNA-binding assays permitted us to generate a high-confident and shortlist of Camelina TFs involved in controlling lipid metabolism during seed development.
Project description:This study was performed to investigate assess the impacts of CO and/or CM containing diets on Atlantic salmon hepatic gene expression in order to identify candidate molecular biomarkers of responses to camelina-containing diets. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial (Control diet: FO; Test diet: 100% FO replacement with CO, with solvent-extracted FM and inclusion of 10% CM (100COSEFM10CM). A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to FO controls at week 16.
2015-05-12 | GSE56784 | GEO
Project description:Hippobosca camelina De novo whole genome sequencing
Project description:Camelina sativa (hereafter Camelina) has emerged as a promising platform for metabolic engineering due to its short lifecycle, high seed oil content, and amenability to transformation. Previous work has demonstrated the successful introduction of non‑native pathways for the synthesis of very long chain polyunsaturated fatty acids (VLC‑PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These achievements required the coordinated expression of up to seven heterologous genes encoding desaturases and elongases from microalgae and other marine organisms. Although the accumulation of EPA and DHA in Camelina seeds has been well characterised, the impact of introducing such a complex pathway on endogenous seed metabolism remains largely unexplored. Here, we apply these two quantitative proteomics strategies to characterise the seed proteomes of elite EPA‑ and DHA‑producing Camelina lines. Our goals were to: 1. assess global proteomic changes associated with multigene engineering. 2. identify proteomic signatures associated with the differing oil‑yield penalties observed in EPA and DHA lines.
Project description:Camelina sativa (hereafter Camelina) has emerged as a promising platform for metabolic engineering due to its short lifecycle, high seed oil content, and amenability to transformation. Previous work has demonstrated the successful introduction of non‑native pathways for the synthesis of very long chain polyunsaturated fatty acids (VLC‑PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These achievements required the coordinated expression of up to seven heterologous genes encoding desaturases and elongases from microalgae and other marine organisms. Although the accumulation of EPA and DHA in Camelina seeds has been well characterised, the impact of introducing such a complex pathway on endogenous seed metabolism remains largely unexplored. Here, we apply these two quantitative proteomics strategies to characterise the seed proteomes of elite EPA‑ and DHA‑producing Camelina lines. Our goals were to: 1. assess global proteomic changes associated with multigene engineering. 2. identify proteomic signatures associated with the differing oil‑yield penalties observed in EPA and DHA lines. 3. quantify the (relative) abundance of transgene‑encoded enzymes relative to endogenous lipid biosynthetic proteins.
Project description:This study was performed to investigate assess the impacts of CO and/or CM containing diets on Atlantic salmon hepatic gene expression in order to identify candidate molecular biomarkers of responses to camelina-containing diets. Atlantic salmon were fed diets with complete or partial replacement of FO and/or FM with camelina oil (CO) and/or camelina meal (CM) in a 16-week trial (Control diet: FO; Test diet: 100% FO replacement with CO, with solvent-extracted FM and inclusion of 10% CM (100COSEFM10CM). A 44K microarray experiment identified liver transcripts that responded to 100COSEFM10CM (associated with reduced growth) compared to FO controls at week 16. Atlantic salmon were fed for 16 weeks with the FO or 100COSEFM10CM diet (three tanks per diet). Liver samples were taken from 7 fish from each tank at week 16. A universal reference design was used for the microarray experiment. For the test samples, RNA was used from individual livers of fish from the 2 treatment groups: FO and 100COSEFM10CM. For each treatment group we used 9 biological replicates (3 fish from each of 3 tanks). All test samples were labeled with Cy5. The common reference was a pool of 18 RNA samples from livers of fish from all individuals invovled in microarray experiment. The common reference was labeled with Cy3. Each individual test sample was hybridized together with the common reference sample on an array, so the experiment consisted of 18 arrays
Project description:Soil salinity presents a notable challenge to agriculture and to increasing the use marginal lands for farming. Here we provide a detailed analysis of the physiology, chemistry and gene expression patterns in roots and shoots of Camelina sativa in response to salt stress. Salt treatment reduced shoot, but not root length. Root and shoot weight were affected by salt, as was photosynthetic capacity. Salt treatment did not alter micro-element concentration in shoots, but increased macro-element (Ca and Mg) levels. Gene expression patterns in shoots indicated that salt stress may have led to shuttling of Na+ from the cytoplasm to the tonoplast and to an increase in K+ and Ca+2 import into the cytoplasm. In roots, gene expression patterns indicated that Na+ was exported from the cytoplasm by the SOS pathway and that K+ was imported in response to salt. Genes encoding proteins involved in chelation and storage were highly up-regulated in shoots, while metal detoxification appeared to involve various export mechanisms in roots. In shoots, genes involved in secondary metabolism leading to lignin, anthocyanin and wax production were up-regulated, probably to improve desiccation tolerance. Partial genome expression partitioning was observed in roots and shoots based on the expression of homeologous genes from the three C. sativa genomes. Genome I and II were involved in the response to salinity stress to about the same degree, while about 10 % more differentially-expressed genes were associated with Genome III. This study has provided valuable information and insight into the response of camelina to salt stress. Examination of this data and comparison to similar studies in more halophytic species will allow development of even more salt-tolerant varieties of this emerging industrial crop.