RNAseq evaluation of nicotinamide seed treatment analysed in Norway spruce seedlings
Ontology highlight
ABSTRACT: Nicotinamide seed treatment is investigated as a method for production of robust plants. Previous studies have shown that nicotinamide promotes the plant defence system and decreases DNA methylation levels. The purpose of the present work was to learn more about the underlying molecular mechanisms. The RNA was extracted from roots of three months old Norway spruce seedlings treated at seed stage. Stress was an overrepresented biological process of upregulated genes. Stress response genes are involved in adaption to and defence against stress. Upregulated stress response genes in the seedling roots were for example transcription factors MYB77 and LHY and two chitinases. Chitinases defend against biotic stress, such as pine weevils. Epigenetic regulating genes were generally downregulated, such as DDM1 which is known to promote DNA-methylation. Previous works suggest the hypothesis that nicotinamide is a defense signal mediator, which is supported by the present study.
Project description:Current protection strategies against the fungal pathogen Botrytis cinerea rely on a combination of conventional fungicides and host genetic resistance. Defence elicitors can stimulate plant defence mechanisms through a phenomenon known as priming. Priming results on a faster and/or stronger expression of resistance upon pathogen attack. This work aims to study priming of a commercial formulation of the elicitor Chitosan. Treatments with Chitosan result in induced resistance in solanaceous and brassicaceous plants. Large-scale transcriptomic analysis in this study revealed that Chitosan primes gene expression at early time-points after infection. Four conditions were analysed using microarrays: (i) water-treated and non-infected plants (Water + Mock); (ii) Chitosan-treated and non-infected plants (Chitosan + Mock); (iii) water-treated and B. cinerea-infected plants (Water + B. cinerea); (iv) Chitosan-treated and B. cinerea-infected plants (Chitosan + B. cinerea). Inoculations were performed four days after treatment with Chitosan, and leaf discs from four independent plants (biological replicates) per treatment were sampled at 6 h, 9 h and 12 h post-inoculation (hpi) with water mock or B. cinerea spores.
Project description:Mycosphaerella graminicola is the causal agent of Mycosphaerella graminicola infection (STB) disease of wheat. Wheat genotypes vary in their response to this disease. Cultivar (cv.) Longbow is susceptible and cv. Flame is resistant to STB disease, with cv. Flame possessing the STB resistance locus Stb6 that confers resistance to pathogen strain IPO323. Gene expression profiling (conducted using Affymetrix wheat gene chip) identified transcripts that accumulate in leaves of both these wheat cultivars as an early response to M. graminicola strain IPO323 (at 24h post-treatment). At this initial time point, microscopic analysis verified that fungal spores had germinated, but not penetrated the leaves of both genotypes. Results showed that basal defence genes were activated in both the compatible and incompatible interactions. A subset of genes were identified that were more pathogen-responsive in the cv. Flame v. IPO323 incompatible interaction as compared to the cv. Longbow v. IPO323 compatible interaction, including defence genes such as peroxidases, beta-1,3-glucanase, annexin, chitinases, brassinosteroid-associated kinase 1 and a jasmonate-inducible protein.
Project description:In order to identify novel stress-induced signalling peptides, we searched for Arabidopsis thaliana transcripts encoding short proteins (<150 amino acids) with a predicted signal peptide, which were induced upon biotic elicitor treatment (Bjornson et al., 2021). Through this analysis, we identified an uncharacterised family of peptides with 5 predicted members, which we named CTNIP1 to 5 (pronounced catnip) based on relatively conserved residues within the peptides. CTNIP4 is perceived by Arabidopsis, inducing some hallmark outputs of defence (Pattern-Triggered Immunity) signalling. Mass spectrometric analyses indicated that HSL3 may be the receptor mediating CTNIP recognition. Through assaying transcriptomic responses in wild type and hsl3-1 mutants, we were able to confirm similarity of CTNIP and defence responses at the transcriptional level, and the dependence of these responses on HSL3.
Project description:Nanotechnology has the potential to revolutionize agriculture by developing engineered nanomaterials to be used as biostimulants, fertilizers, pesticides or smart sensors. Seed priming may represent an opportunity for nano-enabled plant technology to match economic, agronomic and environmental needs. This study investigates the effects of seed priming mediated by iron oxide magnetic nanoparticles (MNPs) in plants. We performed a multilevel integrated study to understand the basic interactions between MNPs and seeds in pepper (Capsicum annuum). Moreover, phenotypic, physiological and molecular analyses were performed to elucidate the biological impact of MNPs from seed to plant development. Interestingly, our findings show positive effects of MNPs on vegetative growth and a profound impact on pepper gene expression patterns. Indeed, we found 2,204 differentially expressed transcripts in nanoprimed seeds, most of them involved in plant defence mechanisms, potentially establishing a seed memory that might enhance the plant's capacity to counteract diverse forms of stress. In conclusion, this work provides a comprehensive investigation about nanoparticle-seed interactions with interesting implications for agricultural technology.
Project description:We report on the kiwifruit postharvest phase through an approach consisting of 2D-DIGE/nanoLC-ESI-LIT-MS/MS-based proteomic measurements. Kiwifruit samples stored under conventional, cold-based postharvest conditions were sampled at four stages (from fruit harvest to pre-commercialization) and analyzed in comparison protein content. Proteomics showed that proteins associated with disease/defense, energy, protein destination/storage, cell structure and metabolism functions were affected at precise fruit postharvest times. By lining up kiwifruit postharvest processing to a proteomic depiction, this study integrates previous observations on protein content in postharvest pomes treated with specific chemical additives, and provides a reference framework for further studies on the optimization of fruit storage before its commercialization.
Project description:Mitochondrial antioxidant defence was manipulated by dexamthasone inducible RNAi knockdown of the mitochondrial superoxide dismutase (MSD1) to study transcriptional changes in response.
Project description:SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) proteins drive vesicle fusion and contribute to homoeostasis, pathogen defence, cell expansion, and growth in plants. In Arabidopsis thaliana, the two homologous Qa-SNAREs, SYP121 and SYP122 facilitate the majority of secretory traffic to the plasma membrane. In the absence of stress, the single mutants are indistinguishable from wild-type plants, implying a redundancy in their functions. Nonetheless, several studies suggest differences among the secretory cargo of these SNAREs. To address this issue, we conducted an analysis of the proteins secreted by cultured wild-type, syp121 and syp122 mutant Arabidopsis seedlings. Here, we report that a number of cargo proteins are associated differentially with traffic mediated by SYP121 and SYP122. The data also point to important overlaps between the SNAREs. The findings lead us to conclude that the two Qa-SNAREs mediate distinct, but complementary secretory pathways during vegetative plant growth.
Project description:To determine the effect of different temperature on strawberry after harvest, physiological indicator analysis and proteomics analysis were conducted on ripened strawberry (‘Sweet Charlie’) fruit stored at 4 °C, 23 °C, and 37 °C (±2) for 10 or 20 days. Results showed that 4 °C maintained a better visual quality of strawberry, and the weight loss and firmness remained stable within 3 days. Low temperature negatively affected anthocyanin but positively affected soluble sugars. Though anthocyanin content was higher with increasing temperature, anthocyanin synthesis related proteins were downregulated. Higher indole-acetic acid (IAA) content in seeds and lower abscisic acid (ABA) content were found in berry at 4 °C. Antioxidant related proteins were upregulated during storage, showing a significant up-regulation of POD at 4 °C, and AsA-GSH cycle related proteins and heat shock proteins (HSPs) at 37 °C. In addition, overexpressed sugar phosphate/phosphate translocator, 1-aminocyclopropane-1-carboxylate oxidase and aquaporin PIP2-2 had a positive effect in response to low temperature stress for containing higher protopectin content and POD activity.