Project description:Rain-fed plants are subjected to cycles of drought and re-watering. Thus, efficient recovery from drought may be among the key determinants in the success of these plants, yet the mechanisms by which plant recover from drought have been historically understudied. To parse out the specific molecular processes leading to stress recovery, we performed a fine-scale time course of bulk RNA sequencing starting just 15 minutes after rehydration. We revealed that transcriptional drought recovery is an active and rapid process involving activating thousands of recovery-specific genes. To map the immediate recovery responses in diverse leaf-cell-types, we performed a single-nucleus transcriptome analysis of the onset of recovery from long-term moderate drought. Here we show the formation of unique cell states initiated rapidly following plant rehydration. We reveal the activation of a microbial-autonomic induction of the immune system and demonstrate that the onset of recovery leads to increased resistance against pathogens in Arabidopsis (Arabidopsis thaliana), wild tomato (Solanum pennellii) and domesticated tomato (Solanum lycopersicum cv. M82). Our findings uncover that the preventive immune activation was preserved despite extensive selection during tomato domestication. Since rehydration increases microbial proliferation and, thus, the risk for infection, pre-activating immunity may be crucial for plants survival in natural environments. This work lays the foundation for unraveling the complexed processes actively facilitating stress recovery within plant leaves.
Project description:To elucidate the transcriptional landscape during drought recovery we sequenced a fine-scale time-course of drought recovering plants.
Project description:Rain-fed plants are subjected to cycles of drought and re-watering. Thus, efficient recovery from drought may be among the key determinants in the success of these plants, yet the mechanisms by which plant recover from drought have been historically understudied. To parse out the specific molecular processes leading to stress recovery, we performed a fine-scale time course of bulk RNA sequencing starting just 15 minutes after rehydration. We revealed that transcriptional drought recovery is an active and rapid process involving activating thousands of recovery-specific genes. To map the immediate recovery responses in diverse leaf-cell-types, we performed a single-nucleus transcriptome analysis of the onset of recovery from long-term moderate drought. Here we show the formation of unique cell states initiated rapidly following plant rehydration. We reveal the activation of a microbial-autonomic induction of the immune system and demonstrate that the onset of recovery leads to increased resistance against pathogens in Arabidopsis (Arabidopsis thaliana), wild tomato (Solanum pennellii) and domesticated tomato (Solanum lycopersicum cv. M82). Our findings uncover that the preventive immune activation was preserved despite extensive selection during tomato domestication. Since rehydration increases microbial proliferation and, thus, the risk for infection, pre-activating immunity may be crucial for plants survival in natural environments. This work lays the foundation for unraveling the complexed processes actively facilitating stress recovery within plant leaves.
Project description:All organisms experience stress as an inevitable part of life, from single-celled microorganisms to complex multicellular beings. The ability to recover from stress is a fundamental trait that determines the overall resilience of an organism, yet stress recovery is understudied. To understand the stress recovery process, we studied the recovery from drought stress in Arabidopsis thaliana. We performed a fine-scale time series of bulk RNA sequencing starting 15 minutes after rehydration following moderate drought. We reveal that drought recovery is a rapid process involving the activation of thousands of recovery-specific genes. To capture these rapid recovery responses in different leaf cell types, we performed single-nucleus transcriptome analysis at the onset of post-drought recovery, identifying a cell type-specific transcriptional state developing independently across cell types. Furthermore, we reveal a recovery-induced activation of the immune system that occurs autonomously, and which enhances pathogen resistance in vivo in A. thaliana, wild tomato (Solanum pennellii) and domesticated tomato (Solanum lycopersicum cv. M82). Since rehydration promotes microbial proliferation and thereby increases the risk of infection, the activation of drought recovery-induced immunity may be crucial for plant survival in natural environments. These findings indicate that drought recovery coincides with a preventive defense response, unraveling the complex regulatory mechanisms that facilitate stress recovery in different plant cell types.
Project description:Molecular Elasticity and Adjustment of Drought Recovery Dynamics of 14N- and 15N-fertilized Legume Medicago truncatula. Climate change in conjunction with population growth necessitates a systems biology approach to characterize plant drought response and a more thorough understanding of the underlying molecular mechanisms. During drought stress and recovery, the metabolome and proteome regulate and are regulated through diverse mechanisms including synthesis and degradation. In order to study this complex regulation network, a front-end multilevel analysis is presented for the first time, investigating protein turnover, regulatory classes of proteins and metabolites as well as post translational ubiquitination of a target set of proteins during a severe stress and recovery scenario in the model legume Medicago truncatula. Evidence for enhanced translational proteome regulation was observed during drought recovery and functional clusters of differentially dynamic phases during the course of recovery were defined. The data give novel insights into molecular elasticity that enable recovery of drought stressed plants. Additionally, these results offer putative targets and metabolic pathways for future plant-bioengineering towards enhanced drought stress tolerance.
Project description:Jatropha is known for its ability to grow in marginal lands and drought prone areas receiving limited amounts of rainfall. Accordingly, gene discovery in Jatropha will be useful for providing a source of genetic information for the improvement of drought tolerance in crops. In this study, a Jatropha oligomicroarray was developed to evaluate the gene expression profile of Jatropha plants during drought stress response and recovery from stress. When the gene expression patterns were compared between those differentially expressed during exposure to drought stress and re-watering, it was possible to identify 333 genes that are involved in the response to dehydration, while 592 genes were found to be significant during recovery, and 375 genes are associated in both dehydration and recovery. Furthermore, representative genes from the three gene categories were compared to those found in other plant species and a basic understanding on how Jatropha copes with drought and its mechanism for survival in dry conditions is discussed. Taken together, the oligomicroarray that we developed in this study is a useful tool for analyzing expression profiles of Jatropha genes to better understand molecular mechanism underlying drought stress responses as well as other aspects of molecular studies in Jatropha.