Project description:Iron toxicity is one of the most common mineral disorders affecting Oryza sativa production in flooded lowland fields. Efforts have been made to develop new rice varieties tolerant to Fe toxicity (+Fe). Oryza meridionalis is an endemic from Northern Australia and grows in regions with Fe rich soils, which may provide Fe tolerance genes and mechanisms that can be used for adaptive breeding. Aiming to understand tolerance mechanisms in rice, we screened a population of interspecific introgression lines (IL) from a cross between O. sativa and O. meridionalis for the identification of QTLs contributing to Fe excess tolerance. Six putative QTLs were identified. A line carrying one introgression from O. meridionalis on chromosome 9 associated with one QTL for leaf bronzing score was identified as tolerant in terms of lipid peroxidation and electrolyte leakage despite presenting very high shoot Fe concentrations. Further physiological, biochemical, ionomic and transcriptomic analyses showed that the IL tolerance could be partly explained by Fe partitioning between the leaf sheath and culm. After the in silico construction of an interspecific hybrid genome to map the sequences from transcriptomic analysis, we identified 47 and 27 genes from O. meridionalis up and down-regulated, respectively, by Fe treatment on the tolerant IL. Among possible genes associated with shoot-based tolerance, we identified metallothionein-like proteins, genes from glutathione S-transferase family and transporters from ABC and Major Facilitator Superfamily. This is the first work to demonstrate that introgressions of O. meridionalis in O. sativa genome confer increased tolerance to +Fe
Project description:The transcriptomes of resistant BPH15 introgression line and the susceptible recipient line were analyzed using high-throughput RNA sequencing. In total, 2,914 differentially expressed genes (DEGs) were identified. BPH-responsive transcript profiles were distinct between resistant and susceptible plants and between the early stage (6 h after infestation, HAI) and late stage (48 HAI). The key defense mechanism was related to jasmonate signaling, ethylene signaling, receptor kinase, MAPK cascades, Ca2+ signaling, PR genes, transcription factors, and protein post-translational modifications. Note: All samples in SRA were assigned the same sample accession (SRS565690 and SRS565691). This is incorrect as there are different samples, hence Source Name was replaced with new values. Comment[ENA_SAMPLE] contains the original SRA sample accessions.
Project description:Here, we present OryzaPG-DB, a rice proteome database based on shotgun proteogenomics, which incorporates the genomic features of experimental shotgun proteomics data. This version of the database was created from the results of 27 nanoLC-MS/MS runs on a hybrid ion trap-orbitrap mass spectrometer, which offers high accuracy for analyzing tryptic digests from undifferentiated cultured rice cells. Peptides were identified by searching the product ion spectra against the protein, cDNA, transcript and genome databases from Michigan State University, and were mapped to the rice genome. Approximately 3200 genes were covered by these peptides and 40 of them contained novel genomic features. Users can search, download or navigate the database per chromosome, gene, protein, cDNA or transcript and download the updated annotations in standard GFF3 format, with visualization in PNG format. In addition, the database scheme of OryzaPG was designed to be generic and can be reused to host similar proteogenomic information for other species. OryzaPG is the first proteogenomics-based database of the rice proteome, providing peptide-based expression profiles, together with the corresponding genomic origin, including the annotation of novelty for each peptide.
Project description:A biological phenomenon in which hybrids exhibit superior phenotypes from its parental inbred lines known as heterosis, has been widely exploited in plant breeding and extensively used in crop improvement. Hybrid rice has immense potential to increase yield over other rice varieties and hence is crucial in meeting increasing demand of rice globally. Moreover, the molecular basis of heterosis is still not fully understood and hence it becomes imperative to unravel its genetic and molecular basis. In this context, RNA sequencing technology (RNA-Seq) was employed to sequence transcriptomes of two rice hybrids, Ajay and Rajalaxmi, their parental lines, CRMS31A (sterile line, based on WA-CMS) and CRMS32A (sterile line based on Kalinga-CMS) respectively along with the common restorer line of both hybrids, IR-42266-29-3R at two critical rice developmental stages viz., panicle initiation (PI) and grain filling (GF). Identification of differentially expressed genes (DEGs) at PI and GF stages will further pave the way for understanding heterosis. In addition, such kind of study would help in better understanding of heterosis mechanism and genes up-regulated and down-regulated during the critical stages of rice development for higher yield.
Project description:Rice is one of the most important global food crops, and is also a model organism for cereal research 31 . Complete genome sequencing of rice, together with advances in transcriptomics and proteomics, has had a dramatic impact on plant growth and 5 breeding programs 32 . Genomic analysis of DNA methylation in rice has revealed methylation patterns associated with gene bodies and promoters, and the occurrence of high levels of DNA methylation in the centromeric domain 33 . A genome-wide investigation of acetylation in rice revealed that H3K9ac and H3K27ac are mainly enriched at transcription start sites associated with active transcription 34 . Furthermore, global proteome analysis has shown that phosphorylation and succinylation are involved in diverse cellular and metabolic processes 35, 36 . However, despite these considerable advances in our knowledge, additional large-scale analysis of the lysine acetylome in rice is expected to identify many more Kac sites and acetylated proteins in this improtant crop plant. In this study, affinity enrichment and high-resolution LC-MS/MS were used for large-scale analysis of the lysine acetylome in rice variety Nipponbare. In total, 1353 lysine acetylation sites were detected in 866 protein groups in rice seedlings. Proteomic analysis showed that Kac occurs in proteins involved in diverse biological processes with varied cellular functions and subcellular localization.
Project description:Rice blast is one of the most serious diseases and is caused by Magnaporthe grisea. SHZ-2, an indica cultivar with broad spectrum resistance to multiple races of the blast pathogen, was crossed to TXZ-13, a blast susceptible but high-quality variety, to produce one BC3 line, BC10 line, which showed strong to moderate blast resistance over eight cropping seasons in the field. In this study, we compared the transcription between blast-resistant and -susceptive lines by custom microarray. Keywords: time course, blast infection, disease response
Project description:We analyzed the transcriptome profiles for rice grain from heat-tolerant and -sensitive lines in response to high night temperatures at the early milky stage using the Illumina Sequencing method. On the 8th day after the labeled florets flowered, plants with the same label were transferred to chambers and maintained at a temperature of 38.0â±â0.5°C (treatment) or 25.0â±â0.5°C (control) for the dark period (10 h), and 26.0â±â0.5°C (both treatment and control) for the light period (14 h). Three biological replicates of the temperature treatments were grown under the same conditions. After 48 h of treatment, samples containing 45 grains with labels from the same region (middle to bottom part) of labelled ears were harvested, packed in aluminum foil, and flash-frozen in liquid nitrogen until further use. A total of 12 rice grain samples were harvested, i.e., controls (TC1, TC2 and TC3) and treatments (TT1, TT2 and TT3) of the three biological replicates of the heat-tolerant line, and controls (SC1, SC2 and SC3) and treatments (ST1, ST2 and ST3) of the three biological replicates of the heat-sensitive line.