Project description:To investigate the impact of a plant´s response to abiotic stress on plant defense against subsequent biotic stress, we determined the transcriptional response of Arabidopsis thaliana to low temperature stress (4°C) and subsequent mechanical wounding or larval feeding damage by the herbivores Mamestra brassicae (generalist) and Pieris brassicae (specialist). In total, 21%, 4% and 14% of all genes responsive to M. brassicae, P. brassicae or mechanical wounding were differentially regulated in previously cold-treated compared to untreated plants.
Project description:Oviposition by lepidopteran herbivores on Nicotiana attenuata primes plant defence responses that are induced by the feeding larvae. While oviposition by both the generalist Spodoptera exigua and the specialist Manduca sexta primes the production of defensive phenylpropanoids, their larvae are differentially affected. We investigate here the impact of prior oviposition on the transcriptome and phytohormone levels of plants that were later attacked by larvae to find regulatory signals of this priming. In a full-factorial design, we evaluated the effects of oviposition and herbivory by both species. Oviposition alone had only subtle effects at the transcriptional level. Laval feeding alone induced species-specific plant responses. Larvae of the generalist regulated phytohormones and gene expression stronger than larvae of the specialist. A day after larvae started to feed, we detected no significant alterations of the plant's response to larval feeding due to prior oviposition by conspecific moths. Yet, oviposition by each of the species profoundly influenced the plant's transcriptional and phytohormonal response to feeding larvae of the other species. Remarkably, the species-specific plant responses to larval feeding shifted towards the response normally elicited by larvae of the ovipositing species. Thus, plants may already recognise an insect's identity upon its oviposition.
Project description:In the rhizosphere, plants are exposed to a multitude of different biotic and abiotic factors, to which they respond by exuding a wide range of secondary root metabolites. So far, it has been unknown to which degree root exudate composition is species-specific and is affected by land use, the local impact and local neighborhood under field conditions. In this study, root exudates of 10 common grassland species were analyzed, each five of forbs and grasses, in the German Biodiversity Exploratories using a combined phytometer and untargeted liquid chromatography-mass spectrometry (LC-MS) approach. Redundancy analysis and hierarchical clustering revealed a large set of semi-polar metabolites common to all species in addition to species-specific metabolites. Chemical richness and exudate composition revealed that forbs, such as Plantago lanceolata and Galium species, exuded more species-specific metabolites than grasses. Grasses instead were primarily affected by environmental conditions. In both forbs and grasses, plant functional traits had only a minor impact on plant root exudation patterns. Overall, our results demonstrate the feasibility of obtaining and untargeted profiling of semi-polar metabolites under field condition and allow a deeper view in the exudation of plants in a natural grassland community.
Project description:Here, we investigated the function of the plant-specific SR protein RS33 in pre-mRNA splicing regulation and abiotic stress responses in rice. The loss-of-function mutant, rs33, showed increased sensitivity to salt and low-temperature stress. Genome-wide analyses of gene expression and splicing in seedlings subjected to these stresses identified multiple splice isoforms from stress-responsive genes dependent on RS33. The number of RS33-regulated genes is much higher under low-temperature stress as compared to salt stress. Our results suggest that this plant-specific splicing factor plays crucial and distinct roles during plant adaptation to abiotic stresses.
Project description:Plant growth is severely affected by toxic concentrations of the non-essential heavy metal cadmium (Cd). Comprehensive transcriptome analysis by RNA-Seq following cadmium exposure is required to further understand plant responses to Cd and facilitate future systems-based analyses of the underlying regulatory networks. In this study, rice plants were hydroponically treated with 50 µM Cd for 24 hours. In total, ~60,000 transcripts, including transcripts that could not be characterized by microarray-based approaches, were evaluated and ~36,000 transcripts were responsive to Cd exposure. Among multigenic families that may protect cells from generated ROS and reduce Cd toxicity, prominently upregulated antioxidant enzyme genes were identified. Furthermore, 168 different metal ion transporter genes, which might mediate the transport of transition Cd, responded to Cd exposure. qRT-PCR analysis of randomly selected genes indicated that their expression changed obviously after exposure to various heavy metal stresses. The Cd responsive genes included many abiotic stress (drought, high-salinity, low temperature) responsive genes. Based on further investigation into the expression patterns of abiotic stress regulatory genes such as DREB, part of the signal transduction pathway for Cd exposure was determined to cross-talk with abiotic stress signaling pathways. Our results provide useful information for further studies of the molecular mechanisms of plant adaptation to Cd exposure and the improvement of Cd tolerance in crop species.
Project description:Climate change is having a drastic impact on global agriculture. Indeed stress factors such as elevated temperature, drought and rising atmospheric CO2 reduce arable land surface, crop cultivation and yield and overall sustainable food production on earth. However, plants possess immense innate adaptive plasticity and a more in-depth understanding of the underlying molecular mechanisms is crucial to strategize for sustaining populations under worsening climate change. Brassinosteroids (BRs) are constitutive plant growth regulators that also control plant adaptation to abiotic stress. Downstream components of the BR biosynthetic pathway, BES1/BZR1 play central role in thermomorphogenesis, but involvement of the BR receptors is not well understood. Here, we show that the BRL3 receptor is essential for plant adaptation to warmer environment. The brl3 mutants lack thermal responsiveness and the BRL3 overexpression causes hyper-thermomorphogenesis response. BRL3 activates canonical BRI1 pathway upon elevated temperature. Further, phloem-specific expression of BRL3 completely rescues the growth adaptation defects of the brl3 mutant. This ability of BRL3 represents a previously unknown thermoresponsive mechanism specifically from phloem and uncouples the roles of BR receptors in generic growth vs adaptation to changing climate conditions.
2021-12-06 | GSE190107 | GEO
Project description:Gut microbiota assemblages of generalist predators are driven by local- and landscape-scale factors
| PRJNA962469 | ENA
Project description:Gut microbiota assemblages of generalist predators are driven by local- and landscape-scale factors
Project description:Chromatin modifications play important roles in plant adaptation to abiotic stresses, but the precise function of histone H3 lysine 36 (H3K36) methylation in drought tolerance remains poorly evaluated. Here, we report that SDG708, a specific H3K36 methyltransferase, functions as a positive regulator of drought tolerance in rice.