This study investigated the metabolic adaptive responses to As contamination and As co-contamination with cadmium, lead, and zinc in the leaves and tubers of cherry radish (Raphanus sativus var. sativus Pers.). The response was assessed by measuring malondialdehyde levels, total phenolic content (TPC), total anthocyanin pigment (TAC), growth and stress phytohormone concentration, and free amino acid content. The characteristic As accumulation of single contamination resulted in a decrease in tuber growth. However, in the case of co-contamination, As uptake was influenced by the presence of other potentially toxic elements (PTEs), mainly zinc, with no significant effect on growth. Both contaminated treatments exhibited significant differences in metabolite levels among the organs, along with notable changes in their contents. Increases in malondialdehyde, TPC, and TAC indicated induced oxidative stress and an antioxidant response that was more pronounced by As co-contamination. Also, the results for phytohormones, which showed both increases and decreases, along with selected free amino acids (which showed increases), demonstrated a more significant influence of As co-contamination. Based on these findings, it can be concluded that the response of cherry radish to contaminated treatments exhibited significant differences in the studied parameters, along with variability in the results, reflecting the extent of the effects of PTEs that induce oxidative stress.

• Keywords
• amino acids, hormones, metalloid, stress, vegetable,
• MeSH
• Amino Acids * metabolism   MeSH
• Arsenic * toxicity   MeSH
• Soil Pollutants toxicity   MeSH
• Plant Leaves metabolism   drug effects   MeSH
• Malondialdehyde metabolism   MeSH
• Oxidative Stress drug effects   MeSH
• Raphanus * metabolism   drug effects   growth & development   MeSH
• Plant Growth Regulators * metabolism   MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Amino Acids * MeSH
• Arsenic * MeSH
• Soil Pollutants MeSH
• Malondialdehyde MeSH
• Plant Growth Regulators * MeSH

Global warming is predicted to change the growth conditions for plants and crops in regions at high latitudes (>60° N), including the Arctic. This will be accompanied by alterations in the composition of natural plant and pest communities, as herbivorous arthropods will invade these regions as well. Interactions between previously non-overlapping species may occur and cause new challenges to herbivore attack. However, plants growing at high latitudes experience less herbivory compared to plants grown at lower latitudes. We hypothesize that this finding is due to a gradient of constitutive chemical defense towards the Northern regions. We further hypothesize that higher level of defensive compounds is mediated by higher level of the defense-related phytohormone jasmonate. Because its biosynthesis is light dependent, Arctic summer day light conditions can promote jasmonate accumulation and, hence, downstream physiological responses. A pilot study with bilberry (Vaccinium myrtillus) plants grown under different light regimes supports the hypothesis.

• Keywords
• climate change, jasmonate signaling, light regime, pest distribution, plant defense,
• Publication type
• Journal Article MeSH

Inter-organ communication and the heat stress (HS; 45°C, 6 h) responses of organs exposed and not directly exposed to HS were evaluated in rice (Oryza sativa) by comparing the impact of HS applied either to whole plants, or only to shoots or roots. Whole-plant HS reduced photosynthetic activity (F v /F m and QY_Lss ), but this effect was alleviated by prior acclimation (37°C, 2 h). Dynamics of HSFA2d, HSP90.2, HSP90.3, and SIG5 expression revealed high protection of crowns and roots. Additionally, HSP26.2 was strongly expressed in leaves. Whole-plant HS increased levels of jasmonic acid (JA) and cytokinin cis-zeatin in leaves, while up-regulating auxin indole-3-acetic acid and down-regulating trans-zeatin in leaves and crowns. Ascorbate peroxidase activity and expression of alternative oxidases (AOX) increased in leaves and crowns. HS targeted to leaves elevated levels of JA in roots, cis-zeatin in crowns, and ascorbate peroxidase activity in crowns and roots. HS targeted to roots increased levels of abscisic acid and auxin in leaves and crowns, cis-zeatin in leaves, and JA in crowns, while reducing trans-zeatin levels. The weaker protection of leaves reflects the growth strategy of rice. HS treatment of individual organs induced changes in phytohormone levels and antioxidant enzyme activity in non-exposed organs, in order to enhance plant stress tolerance.

• Keywords
• Oryza sativa (L.), acclimation, antioxidant enzymes, cytokinin oxidase/dehydrogenase (CKX), gene expression, heat shock, jasmonoyl-isoleucine, phytohormones,
• Publication type
• Journal Article MeSH

The function of the plant hormone jasmonic acid (JA) in the development of tomato (Solanum lycopersicum) flowers was analyzed with a mutant defective in JA perception (jasmonate-insensitive1-1, jai1-1). In contrast with Arabidopsis (Arabidopsis thaliana) JA-insensitive plants, which are male sterile, the tomato jai1-1 mutant is female sterile, with major defects in female development. To identify putative JA-dependent regulatory components, we performed transcriptomics on ovules from flowers at three developmental stages from wild type and jai1-1 mutants. One of the strongly downregulated genes in jai1-1 encodes the MYB transcription factor SlMYB21. Its Arabidopsis ortholog plays a crucial role in JA-regulated stamen development. SlMYB21 was shown here to exhibit transcription factor activity in yeast, to interact with SlJAZ9 in yeast and in planta, and to complement Arabidopsis myb21-5 To analyze SlMYB21 function, we generated clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR associated protein 9 (Cas9) mutants and identified a mutant by Targeting Induced Local Lesions in Genomes (TILLING). These mutants showed female sterility, corroborating a function of MYB21 in tomato ovule development. Transcriptomics analysis of wild type, jai1-1, and myb21-2 carpels revealed processes that might be controlled by SlMYB21. The data suggest positive regulation of JA biosynthesis by SlMYB21, but negative regulation of auxin and gibberellins. The results demonstrate that SlMYB21 mediates at least partially the action of JA and might control the flower-to-fruit transition. .

• MeSH
• Cyclopentanes metabolism   MeSH
• Down-Regulation MeSH
• Phenotype MeSH
• Fertility MeSH
• Gibberellins metabolism   MeSH
• Flowers genetics   physiology   MeSH
• Indoleacetic Acids metabolism   MeSH
• Mutation MeSH
• Plant Infertility MeSH
• Fruit genetics   physiology   MeSH
• Oxylipins metabolism   MeSH
• Arabidopsis Proteins genetics   metabolism   MeSH
• Gene Expression Regulation, Plant * MeSH
• Plant Growth Regulators metabolism   MeSH
• Plant Proteins genetics   metabolism   MeSH
• Solanum lycopersicum genetics   physiology   MeSH
• Transcription Factors genetics   metabolism   MeSH
• Ovule genetics   physiology   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Cyclopentanes MeSH
• Gibberellins MeSH
• jasmonic acid MeSH Browser
• Indoleacetic Acids MeSH
• MYB21 protein, Arabidopsis MeSH Browser
• Oxylipins MeSH
• Arabidopsis Proteins MeSH
• Plant Growth Regulators MeSH
• Plant Proteins MeSH
• Transcription Factors MeSH

Phospholipases (PLs) are lipid-hydrolyzing enzymes known to have diverse signaling roles during plant abiotic and biotic stress responses. They catalyze lipid remodeling, which is required to generate rapid responses of plants to environmental cues. Moreover, they produce second messenger molecules, such as phosphatidic acid (PA) and thus trigger or modulate signaling cascades that lead to changes in gene expression. The roles of phospholipases in plant abiotic and biotic stress responses have been intensively studied. Nevertheless, emerging evidence suggests that they also make significant contributions to plants' cellular and developmental processes. In this mini review, we summarized recent advances in the study of the cellular and developmental roles of phospholipases in plants.

• Keywords
• cellular functions, phosphatidic acid, phospholipase A, phospholipase C, phospholipase D, phospholipases, phytohormones, plant development,
• Publication type
• Journal Article MeSH
• Review MeSH

Phytohormones are crucial molecules regulating plant development and responses to environmental challenges, including abiotic stresses, microbial and insect attacks. Most notably, phytohormones play important roles in the biosynthesis of lignocellulosics. Jasmonates are involved in secondary growth and secondary metabolism, such as phenylpropanoids and lignin biosyntheses. At the physiological and molecular levels, the actions of phytohormones depend on subtle concentration changes, as well as antagonistic equilibria between two or more of these molecules. In this article, we investigate the consequences of jasmonic acid (JA) spraying on young hemp hypocotyls. First, we show that JA application results in changes in the monomeric composition of lignin. Second, we highlight that, five days after application, JA leads to an increase in salicylic acid (SA) content in hemp hypocotyls. These results are discussed in the light of the known antagonism between JA and SA at both the physiological and molecular levels.

• Keywords
• Hemp, jasmonic acid, lignin composition, salicylic acid,
• MeSH
• Cannabis drug effects   metabolism   MeSH
• Cyclopentanes pharmacology   MeSH
• Hypocotyl drug effects   growth & development   metabolism   MeSH
• Salicylic Acid pharmacology   MeSH
• Lignin metabolism   MeSH
• Oxylipins pharmacology   MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Cyclopentanes MeSH
• jasmonic acid MeSH Browser
• Salicylic Acid MeSH
• Lignin MeSH
• Oxylipins MeSH

: Jasmonic acid (JA) and its related derivatives are ubiquitously occurring compounds of land plants acting in numerous stress responses and development. Recent studies on evolution of JA and other oxylipins indicated conserved biosynthesis. JA formation is initiated by oxygenation of α-linolenic acid (α-LeA, 18:3) or 16:3 fatty acid of chloroplast membranes leading to 12-oxo-phytodienoic acid (OPDA) as intermediate compound, but in Marchantiapolymorpha and Physcomitrellapatens, OPDA and some of its derivatives are final products active in a conserved signaling pathway. JA formation and its metabolic conversion take place in chloroplasts, peroxisomes and cytosol, respectively. Metabolites of JA are formed in 12 different pathways leading to active, inactive and partially active compounds. The isoleucine conjugate of JA (JA-Ile) is the ligand of the receptor component COI1 in vascular plants, whereas in the bryophyte M. polymorpha COI1 perceives an OPDA derivative indicating its functionally conserved activity. JA-induced gene expressions in the numerous biotic and abiotic stress responses and development are initiated in a well-studied complex regulation by homeostasis of transcription factors functioning as repressors and activators.

• Keywords
• JA biosynthetic enzymes, JA bypass, JA signaling, Jasmonic acid (JA) metabolites, active JA compounds, occurrence, transcription factors,
• MeSH
• Chloroplasts metabolism   MeSH
• Cyclopentanes metabolism   MeSH
• Species Specificity MeSH
• alpha-Linolenic Acid metabolism   MeSH
• Marchantia metabolism   MeSH
• Fatty Acids metabolism   MeSH
• Bryopsida metabolism   MeSH
• Metabolic Networks and Pathways MeSH
• Fatty Acids, Unsaturated metabolism   MeSH
• Oxylipins metabolism   MeSH
• Peroxisomes metabolism   MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• 12-oxophytodienoic acid MeSH Browser
• Cyclopentanes MeSH
• jasmonic acid MeSH Browser
• alpha-Linolenic Acid MeSH
• Fatty Acids MeSH
• Fatty Acids, Unsaturated MeSH
• Oxylipins MeSH