Project description:To better understand the regulatory mechanisms of water stress response in wheat, the transcript profiles in roots of two wheat genotypes, namely, drought tolerant 'Luohan No.2' (LH) and drought susceptible 'Chinese Spring' (CS) under water-stress were comparatively analyzed by using the Affymetrix wheat GeneChip®. A total of 3831 transcripts displayed 2-fold or more expression changes, 1593 transcripts were induced compared with 2238 transcripts were repressed, in LH under water-stress; Relatively fewer transcripts were drought responsive in CS, 1404 transcripts were induced and 1493 were repressed. Comparatively, 569 transcripts were commonly induced and 424 transcripts commonly repressed in LH and CS under water-stress. 689 transcripts (757 probe sets) identified from LH and 537 transcripts (575 probe sets) from CS were annotated and classified into 10 functional categories, and 74 transcripts derived from 80 probe sets displayed the change ratios no less than 16 in LH or CS. Several kinds of candidate genes were differentially expressed between the LH and CS, which could be responsible for the difference in drought tolerance of the two genotypes. Two common wheat (Triticum aestivum L.) cultivars, Luohan No.2 (LH) and Chinese Spring (CS), were used for this study. Seedlings at the two leaf stage were stressed by cultured in PEG solutions for 6h, and some other seedlings were cultured in tap water as control. Root samples of LH and CS at 6h after the stress treatment and untreated control were prepared for microarray analysis.
Project description:To better understand the regulatory mechanisms of water stress response in wheat, the transcript profiles in roots of two wheat genotypes, namely, drought tolerant 'Luohan No.2' (LH) and drought susceptible 'Chinese Spring' (CS) under water-stress were comparatively analyzed by using the Affymetrix wheat GeneChip®. A total of 3831 transcripts displayed 2-fold or more expression changes, 1593 transcripts were induced compared with 2238 transcripts were repressed, in LH under water-stress; Relatively fewer transcripts were drought responsive in CS, 1404 transcripts were induced and 1493 were repressed. Comparatively, 569 transcripts were commonly induced and 424 transcripts commonly repressed in LH and CS under water-stress. 689 transcripts (757 probe sets) identified from LH and 537 transcripts (575 probe sets) from CS were annotated and classified into 10 functional categories, and 74 transcripts derived from 80 probe sets displayed the change ratios no less than 16 in LH or CS. Several kinds of candidate genes were differentially expressed between the LH and CS, which could be responsible for the difference in drought tolerance of the two genotypes.
Project description:Fusarium graminearum (F.g) is responsible for Fusarium head blight (FHB), which is a destructive disease of wheat that accumulates mycotoxin such as deoxynivalenol (DON) and makes its quality unsuitable for end use. Several FHB resistant varieties development is going on world-wide. However the complete understanding of wheat defence response, pathogen (Fusarium graminearum) disease development mechanism and the gene crosstalk between organisms is still unclear. In our study focused to analyse pathogen (F. graminearum) molecular action in different Fusarium head blight resistance cultivars during the disease development. To understand the Fusarium graminearum pathogen molecular reaction, microarray gene expression analysis was carried out by using Fusarium graminearum (8 x 15k) Agilent arrays at two time points (3 & 7 days after infection) on three wheat genotypes (Japanese landrace cv. Nobeokabouzu-komugi - highly resistant, Chinese cv. Sumai 3 - resistant and Australian cv. Gamenya - susceptible), which spikes infected by Fusarium graminearum ‘H-3’strain. During the disease development the pathogen biomass as well as the expression of Trichothecene biosynthesis involved genes (Tri genes) in three wheat cultivars was determined. In our material no relation between fungus biomass and the disease symptoms were observed, however, it showed relation with fungus virulence factors expression (Tri genes). For the first time, we report the nature of Fusarium graminearum gene expression in the FHB-highly resistant cv. Nobeokabouzu-komugi during the disease development stage and the possible underlying molecular response.
Project description:High plasticity of common wheat is attributed to the captured and polyploidization-promoted diversity. However, uncontrolled subgenome diversification can lead to hybrid conflict and dysgenesis, resulting in decreased diversity. How genomic diversity is maintained and interpreted to increase plasticity is unclear. By data-mining from the binding of 193 genome-wide trans-factors and genetic perturbations in common wheat, we identified LHP1 as a major regulator of subgenome-diversified defense genes, enhancer RNAs, and metabolite synthesis-related gene clusters via H3K27me3. Stripe rust infection leads to a global decrease in LHP1-mediated H3K27me3, deprivation of which enhances common wheat stripe rust resistance. We also revealed the consistency between subgenome diversity and population diversity, potentially promoted by LHP1, implying the recent diversification preferentially occurred in the captured subgenome-diversified regions regulated by LHP1. Thus, common wheat benefitted from multi-faced role of LHP1 in promoting sequence diversity and repressing subgenome-diversified defenses; this constraint is eliminated by pathogen infections, enabling timely release and fixation of favorable variations, conferring the evolutionary advantage and high plasticity of common wheat.
Project description:The study was conducted in order to find out the differential change in the transcript of tolerant and susceptible wheat cultivar under heat stress and to decipher the mechanism of thermotolerance in wheat by identifying novel genes and transcription factors involved in the pathways. Wheat cultivar HD2985 (thermotolerant) and HD2329 (thermosusceptible) were exposed to heat stress of 42 degree for 4h at pollination stage and samples were collected from both control and heat shock treated plants for further characterization.