Project description:Arabidopsis thaliana plants that have experienced an initial exposure to dehydration stress (“trained plants”) have an increased ability to maintain leaf relative water content (RWC) during subsequent stresses than plants experiencing the stress for the first time and transcription of selected dehydration response genes is altered during successive exposures to dehydration stress. This physiological and transcriptional behavior of trained plants is consistent with a “memory “of an earlier stress. It is unknown whether such memory is present in other Angiosperm lineages and whether it is an evolutionarily conserved response to stress. Here, we analyzed the behavior and transcriptomes of maize (Zea mays) plants experiencing multiple dehydration stresses and compare them with responses of the evolutionarily distant A. thaliana. We found structurally related genes in maize that displayed the same memory-type responses as in A. thaliana, providing evidence of the conservation of function and transcriptional memory in the evolution of plants’ dehydration stress response systems. Similar to A. thaliana, trained Z. mays plants retained higher RWC during dehydration stress than untrained plants, due in part to maintaining reduced stomatal conductance, despite full recovery of RWC, after the first stress. Divergent transcriptional memory responses were also expressed, suggesting diversification of function among stress memory genes. Some dehydration stress memory genes were also shared with other stress and hormone responding pathways, indicating complex and dynamic interactions between different plant signaling networks. The results provide new insight into how plants respond to multiple dehydration stresses and provide a platform for studies of the functions of memory genes in adaptive responses to water deficit in monocot and eudicot plants .
Project description:Arabidopsis plants that have experienced stress from water withdrawal show an improved ability to tolerate subsequent exposures as a ‘memory’ from the previous stress. This physiological stress memory is associated with ‘transcriptional memory’ illustrated by a subset of dehydrations stress responding genes that produce significantly different transcript amounts during repeated dehydration stresses relative to their response in the first. Here we report the genome-wide representation of dehydration stress transcriptional memory genes in A. thaliana. We identify four novel transcription patterns in response to repeated dehydration stress treatments. The nature of the proteins encoded by genes from each type of memory-response pattern is analyzed and the consequences of the genes’ memory behavior are considered in the context of possible biological relevance. The memory behavior of genes co-regulated by the dehydration/ABA and other abiotic stress and hormone responding pathways suggested that the crosstalk at the transcriptional level between them was affected as well. The intensity and the nature of specific biochemical, membrane, chloroplast, and stress response-related interactions during multiple exposures to dehydration stress are different from the responses to a single dehydration stress. The results reveal additional, hitherto unknown, levels of complexity of the plants’ transcriptional behavior when adjusting and adapting to recurring water deficits.
Project description:To understand the role of SMAX1 and SMXL2 in water stress response, we have carried out comparative expression analysis of the smax1 smxl2 mutant and WT plants under dehydration and well-watered (control) conditions. Aligent's whole Arabidopsis Gene Expression Microarray (G2519F-021169, V4, 4x44K) was used.
Project description:To explore the role and target of chloroplast proteases under heat stress, thylakoid membranes were isolated from wild-type and mutant chloroplast thylakoid membrane-localized proteases after heat stress and subjected to comparative quantification by LC-MS/MS analysis using the spectral counting method.
Project description:To understand the Abscisic Acid (ABA) signaling in response to dehydration stress, we performed analysis of gene expression using Arabidopsis wild-type plants and the nced3-2 mutant under dehydration stress. The nced3-2 mutant is an Arabidopsis T-DNA tagged knock-out mutant of the NCED3 gene, which has an essential role in dehydration-inducible ABA biosynthesis. Arabidopsis plants were grown in in soil (verdenite 40 mmΦ, Verde Co., Ltd., Kanagawa, Japan) in a cell strainer (Falcon, 40 μm; Corning Inc., NY, USA). Plants were grown at 22°C for 3 weeks under illumination (40â60 μmol m-2s-1; 16 h light/8 h darkness). Three-week-old plants were exposed to dehydration stress by being denied water for 6, 24, 48, or 72 h.
Project description:To understand the role of KUF1 in water stress response, we have carried out comparative expression analysis of the kuf1-1 mutant and WT plants under dehydration and well-watered (control) conditions. Aligent’s whole Arabidopsis Gene Expression Microarray (G2519F-021169, V4, 4x44K) was used.
Project description:Comparative expression analysis of the Arabidopsis CK-signaling ahp4-1 mutant and wild type (WT) plants (Col-0) under dehydration conditions
Project description:To understand the role of CK-signaling components in water stress response, we have carried out comparative expression analysis of the CK-signaling ahp4-1 mutant and WT plants under dehydration and well-watered (control) conditions. Aligent’s whole Arabidopsis Gene Expression Microarray (G2519F-021169, V4, 4x44K) was used.