Project description:Durum wheat (Triticum turgidum L. ssp. durum) is a major cereal and staple in the semi-arid regions of the Mediterranean Basin. After assembling the Platinum-quality reference genome for Svevo durum wheat cultivar, coupling PACBIO HiFi long read 35X sequencing with BIONANO Optical Mapping and Hi-C conformation capture, a complete and accurate gene annotation was then obtained by coupling Illumina RNASeq and Nanopore Isoseq sequencing from multiple tissues. Gene expression was investigated in spikelets inoculated with Fusarium graminearum and in not infected controls to profile the transcriptional regulation of Fusarium head blight infection.
Project description:Durum wheat (Triticum turgidum L. ssp. durum) is a major cereal and staple in the semi-arid regions of the Mediterranean Basin. It originates from BBAA wild tetraploid domesticated in Neolithic era, later evolving to domesticated emmer and then to up to 11 T. turgidum subspecies, including durum wheat landraces and modern cultivars. Tetraploid wheat is the donor of the A and B genomes of hexaploid bread wheat (DDAABB), representing therefore a valuable source of genetic variability and beneficial alleles for both durum and bread wheat breeding. After assembling the Platinum-quality reference genome for Svevo durum wheat cultivar coupling PACBIO HiFi long read 35X sequencing with BIONANO Optical Mapping and Hi-C conformation capture, a complete and accurate gene annotation was then obtained by coupling Illumina RNASeq and Nanopore Isoseq sequencing from multiple tissues. The expression of 68,154 high confidence genes together with more than 100,000 low confidence, TE-related or long non-coding genes was investigated on 30 diverse tissues from grain, root, leaf, and spike samples across multiple developmental time points to create a transcriptional atlas of durum wheat development.
Project description:Durum wheat (Triticum turgidum L. ssp. durum) is a major cereal and staple in the semi-arid regions of the Mediterranean Basin. After assembling the Platinum-quality reference genome for Svevo durum wheat cultivar, coupling PACBIO HiFi long read 35X sequencing with BIONANO Optical Mapping and Hi-C conformation capture, a complete and accurate gene annotation was then obtained by coupling Illumina RNASeq and Nanopore Isoseq sequencing from multiple tissues. The gene expression was investigated in root and shoot samples collected from plants grown under control condition or subjected to heat, salinity and osmotic stresses or to nitrogen application to create a transcriptional atlas of durum wheat response to abiotic stresses.
Project description:We have employed whole genome microarray expression profiling as a discovery platform to identify genes to alter the transcript accumulation levels in grass-clump dwarf lines, which are synthetic hexaploid lines from triploid hybrids crossed between tetraploid wheat (Triticum turgidum ssp. durum cv. Langdon or T. turgidum ssp. carthlicum) and diploid wheat progenitor Aegilops tauschii (KU2025). No up-regulation of defense-related genes was observed under the normal temperature, and down-regulation of wheat APETALA1-like MADS-box genes, considered to act as flowering promoters, was found in the grass-clump dwarf lines. Together with small RNA sequencing analysis of the grass-clump dwarf line, unusual expression of the miR156/SPLs module could explain the grass-clump dwarf phenotype.
Project description:The increasing presence of nanoplastics in agricultural soils, particularly polystyrene nanoplastics (PSNPs), poses a novel and underestimated threat to crop productivity and food security. The impact of plastics has recently been investigated in cereals confirming that PSNPs can be absorbed by plants through the roots and subsequently translocated to other plant organs. While extensive research has focused on bread wheat, the effects of PSNPs on durum wheat (Triticum turgidum ssp. durum) remain largely unexplored. In this study, we examined the transcriptomic response to PSNPs exposure in two durum wheat lines: Kronos (wild type) and MRP3, a low-phytate mutant generated via TILLING. The MRP3 line carries deleterious mutation in the Multidrug Resistance-Associated Protein 3 (MRP3) genes, which encodes a vacuolar transporter of phytic acid.
Project description:Wheat is one of the most significant crops in terms of human consumption in the world. In a climate change scenario, extreme weather event such as heatwaves will be more frequent especially during the grain-filling (GF) stage and could affect grain weight and quality of crops. Molecular mechanisms underlying the response to short heat stress (HS) have been widely reported for the hexaploid wheat (Triticum aestivum) but the regulatory heat stress mechanisms in tetraploid durum wheat (Triticum turgidum ssp. durum) remain partially understood. In this work, we performed a transcriptomic analysis of durum wheat grains to HS during early GF to identify key HS response genes and their predicted regulatory networks under glasshouse conditions.
Project description:We have employed whole genome microarray expression profiling as a discovery platform to identify genes to alter the transcript accumulation levels in grass-clump dwarf lines, which are synthetic hexaploid lines from triploid hybrids crossed between tetraploid wheat (Triticum turgidum ssp. durum cv. Langdon or T. turgidum ssp. carthlicum) and diploid wheat progenitor Aegilops tauschii (KU2025). No up-regulation of defense-related genes was observed under the normal temperature, and down-regulation of wheat APETALA1-like MADS-box genes, considered to act as flowering promoters, was found in the grass-clump dwarf lines. Together with small RNA sequencing analysis of the grass-clump dwarf line, unusual expression of the miR156/SPLs module could explain the grass-clump dwarf phenotype. Expression patterns were compared between the three synthetic hexaploid lines showing the wild-type phenotype (as a reference) and grass-clump dwarf. Total RNA samples were isolated from crown tissues of the plants grown at 24°C under long day (18-h light and 6-h dark) condition for 8 weeks. Two independent experiments were conducted in each exprement.
Project description:Background: MicroRNAs are endogenous small noncoding RNAs that play critical roles in plant abiotic stress responses. The interaction between miRNA-mRNA targets and their regulatory pathways in response to water deficit stress has been investigated in many plant species. However, the miRNA transcriptome of durum wheat (Triticum turgidum L. ssp. durum) is poorly characterised, with little known about miRNA functions related to water deficit stress. Yield loss in durum wheat can be exacerbated due to minimal rainfall in the early reproductive stages of development during Spring in Australia. This study describes genotypic differences in the miRNAome between water deficit tolerant/sensitive durum, using flag leaf and developing head tissue, and more specifically identifies miRNAs associated with water deficit stress. Results: Small RNA libraries (96 in total) were constructed from flag leaf and developing head tissues of four durum genotypes (Tamaroi, Yawa, EGA Bellaroi, Tjilkuri), with or without water deficit stress. Illumina sequencing and subsequent analysis detected 110 conserved miRNAs and 159 novel candidate miRNA hairpins. Statistical analysis of the abundance of sequencing reads revealed 66 conserved miRNAs and five novel miRNA hairpins showing differential expression under water deficit stress. During stress, several conserved and novel miRNAs showed unambiguous inverted regulatory profiles between the durum genotypes studied. Several miRNAs were also identified to have different abundance in the flag leaf compared to the developing head regardless of treatment. Predicted mRNA targets from four novel durum miRNAs were characterised using Gene Ontology (GO) which revealed functions common to stress responses and plant development. Conclusion: For the first time, we present a comprehensive study of the miRNA transcriptome of flag leaf and developing head tissues in different durum genotypes under water deficit stress. The identification of differentially expressed miRNAs provides molecular evidence that miRNAs are potential determinants of water stress tolerance in durum wheat. GO analysis of predicted targets contributes to the understanding of genotype-specific physiological responses leading to stress tolerance capacity. Further functional analysis of specific stress responsive miRNAs identified, and their interaction with mRNA targets is ongoing and will assist in developing future durum wheat varieties with enhanced water deficit stress tolerance.
Project description:Roots adaptation to drought stress was analyzed using transcriptome and metabolomics profiles in two wild emmer wheat (Triticum turgidum ssp. dicoccoides) genotypes: Y12-3 (drought resistance) and A24-39 (drought susceptible).
Project description:Crop reproduction is highly sensitive to water-deficit and heat stress. The molecular networks of stress adaptation and grain development in tetraploid wheat (T. turgidum durum) are not well understood. Small RNAs (sRNAs) are important epigenetic regulators connecting the transcriptional and post-transcriptional regulatory networks. This study presents the first multi-omics analysis of the sRNAome, transcriptome and degradome in T. turgidum developing grains, under single and combined water-deficit and heat stress. We identified 690 microRNAs (miRNAs), with 84 being novel, from 118 sRNA libraries. Complete profiles of differentially expressed miRNA (DEMs) specific to genotypes, stress types and different reproductive time-points are provided. The first degradome-seq report for developing durum grains discovered a significant number of new target genes regulated by miRNAs post-transcriptionally. Transcriptome-seq profiled 53,146 T. turgidum genes, with differentially expressed genes (DEGs) enriched in functional categories such as nutrient metabolism, cellular differentiation, transport, reproductive development and hormone transduction pathways. miRNA-mRNA networks that affect grain characteristics such as starch synthesis and protein metabolism were constructed, based on integrated analysis of the three omics. This study provides a substantial amount of novel information on the post-transcriptional networks in T. turgidum grains, which will facilitate innovations for breeding programs aiming to improve crop resilience and grain quality.