Loss of DET1 in High Pigment 2 Tomato Prevents High Temperature Repression of Anthocyanin Biosynthesis in Fruit Through HY5 Stabilization.

Global warming impacts several aspects of plant physiology, with important negative effects on crop yield and production of secondary metabolites, such as anthocyanins. The anthocyanin content of vegetables and fruits has attracted public interest in the last two decades due to its health benefits, leading to the development of novel anthocyanin-enriched plant varieties, including purple tomato lines. In purple tomato fruits anthocyanin biosynthesis is largely regulated by light through HY5, whose levels are in turn controlled by COP1-targeted destabilization, and increasing temperatures strongly impair anthocyanin accumulation in the fruit peel.

The transcription factor ORA59 represses hypoxia responses during Botrytis cinerea infection and reoxygenation.

Transcription factors belonging to the large ethylene response factor (ERF) family are involved in plant responses to biotic and abiotic stresses. Among the ERFs, OCTADECANOID-RESPONSIVE ARABIDOPSIS 59 (ORA59) integrates ethylene and jasmonic acid signaling to regulate resistance to necrotrophic pathogens. The ERF group ERFVII encodes oxygen-labile proteins that are required for oxygen sensing and are stabilized by hypoxia established at the site of Botrytis (Botrytis cinerea) infection.

Geography, altitude, agriculture, and hypoxia.

Reduced oxygen availability (hypoxia) represents a key plant abiotic stress in natural and agricultural systems, but conversely it is also an important component of normal growth and development. We review recent advances that demonstrate how genetic adaptations associated with hypoxia impact the known plant oxygen-sensing mechanism through the PLANT CYSTEINE OXIDASE N-degron pathway. Only 3 protein substrates of this pathway have been identified, and all adaptations identified to date are associated with the most important of these, the group VII ETHYLENE RESPONSE FACTOR transcription factors.

Environmental genome-wide association studies across precipitation regimes reveal that the E3 ubiquitin ligase MBR1 regulates plant adaptation to rainy environments.

In an era characterized by rapidly changing and less-predictable weather conditions fueled by the climate crisis, understanding the mechanisms underlying local adaptation in plants is of paramount importance for the conservation of species. As the frequency and intensity of extreme precipitation events increase, so are the flooding events resulting from soil water saturation. The subsequent onset of hypoxic stress is one of the leading causes of crop damage and yield loss.

Plant quiescence strategy and seed dormancy under hypoxia.

Plant quiescence and seed dormancy can be triggered by reduced oxygen availability. Under water, oxygen depletion caused by flooding can culminate in a quiescent state, which is a plant strategy for energy preservation and survival. In adult plants, a quiescent state can be activated by sugar starvation, leading to metabolic depression.

Root photosynthesis prevents hypoxia in the epiphytic orchid .

Orchids (Phalaenopsis spp.) growing in tropical and subtropical regions are epiphytes. As such, they grow on trees with the root system utilised to anchor themselves to tree branches.

Seed bacterial microbiota in post-submergence tolerant and sensitive barley genotypes.

Flooding is a predominant abiotic stress for cultivated plants, including barley. This cereal crop shows a large adaptability to different environmental conditions, suggesting the presence of key traits to tolerate adverse conditions. During germination, genetic variations account for dissimilarities in flooding tolerance.

Spatiotemporal oxygen dynamics in young leaves reveal cyclic hypoxia in plants.

Oxygen is essential for plant growth and development. Hypoxia occurs in plants due to limited oxygen availability following adverse environmental conditions as well in hypoxic niches in otherwise normoxic environments. However, the existence and functional integration of spatiotemporal oxygen dynamics with plant development remains unknown.

In pursuit of purple: anthocyanin biosynthesis in fruits of the tomato clade.

Over the past decade, progress has been made in the characterization of anthocyanin synthesis in fruits of plants belonging to the tomato clade. The genomic elements underlying the activation of the process were identified, providing the basis for understanding how the pathway works in these species. In this review we explore the genetic mechanisms that have been characterized to date, and detail the various wild relatives of the tomato, which have been crucial for recovering ancestral traits that were probably lost during evolution from green-purple to yellow and red tomatoes.

Recent progress in understanding the cellular and genetic basis of plant responses to low oxygen holds promise for developing flood-resilient crops.

With recent progress in active research on flooding and hypoxia/anoxia tolerance in native and agricultural crop plants, vast knowledge has been gained on both individual tolerance mechanisms and the general mechanisms of flooding tolerance in plants. Research on carbohydrate consumption, ethanolic and lactic acid fermentation, and their regulation under stress conditions has been accompanied by investigations on aerenchyma development and the emergence of the radial oxygen loss barrier in some plant species under flooded conditions. The discovery of the oxygen-sensing mechanism in plants and unravelling the intricacies of this mechanism have boosted this very international research effort.

Identification of novel plant cysteine oxidase inhibitors from a yeast chemical genetic screen.

Hypoxic responses in plants involve Plant Cysteine Oxidases (PCOs). They catalyze the N-terminal cysteine oxidation of Ethylene Response Factors VII (ERF-VII) in an oxygen-dependent manner, leading to their degradation via the cysteine N-degron pathway (Cys-NDP) in normoxia. In hypoxia, PCO activity drops, leading to the stabilization of ERF-VIIs and subsequent hypoxic gene upregulation.

ERFVII transcription factors and their role in the adaptation to hypoxia in Arabidopsis and crops.

In this review, we focus on ethylene transcription factors (ERFs), which are a crucial family of transcription factors that regulate plant development and stress responses. ERFVII transcription factors have been identified and studied in several crop species, including rice, wheat, maize, barley, and soybean. These transcription factors are known to be involved in regulating the plant's response to low oxygen stress-hypoxia and could thus improve crop yields under suboptimal growing conditions.

Novel R2R3 MYB transcription factors regulate anthocyanin synthesis in Aubergine tomato plants.

Background: A high content in anthocyanins, for their health beneficial properties, represents an added value for fruits and vegetables. Tomato (Solanum lycopersicum) is one of the most consumed vegetables worldwide and is rich in vitamins and carotenoids. In recent years, purple-skinned tomatoes, enriched of anthocyanins, were produced recovering allelic variants from wild Solanum species.

Target of rapamycin signaling couples energy to oxygen sensing to modulate hypoxic gene expression in .

Plants respond to oxygen deprivation by activating the expression of a set of hypoxia-responsive genes (HRGs). The master regulator of this process is a small group of transcription factors belonging to group VII of the ethylene response factors (ERF-VIIs). ERF-VIIs are highly unstable under aerobic conditions due to the continuous oxidation of their characteristic Cys residue at the N terminus by plant cysteine oxidases (PCOs).

Group VII ethylene response factors, MtERF74 and MtERF75, sustain nitrogen fixation in Medicago truncatula microoxic nodules.

Group VII ethylene response factors (ERF-VII) are plant-specific transcription factors (TFs) known for their role in the activation of hypoxia-responsive genes under low oxygen stress but also in plant endogenous hypoxic niches. However, their function in the microaerophilic nitrogen-fixing nodules of legumes has not yet been investigated. We investigated regulation and the function of the two Medicago truncatula ERF-VII TFs (MtERF74 and MtERF75) in roots and nodules, MtERF74 and MtERF75 in response to hypoxia stress and during the nodulation process using an RNA interference strategy and targeted proteolysis of MtERF75.

Improvement in fruit yield and tolerance to salinity of tomato plants fertigated with micronutrient amounts of iodine.

Iodine is an essential micronutrient for humans, but its role in plant physiology was debated for nearly a century. Recently its functional involvement in plant nutrition and stress-protection collected the first experimental evidence. This study wanted to examine in depth the involvement of iodine in tomato plant nutrition, also evaluating its potential on salt stress tolerance.

The vacuolar H+/Ca transporter CAX1 participates in submergence and anoxia stress responses.

A plant's oxygen supply can vary from normal (normoxia) to total depletion (anoxia). Tolerance to anoxia is relevant to wetland species, rice (Oryza sativa) cultivation, and submergence tolerance of crops. Decoding and transmitting calcium (Ca) signals may be an important component to anoxia tolerance; however, the contribution of intracellular Ca transporters to this process is poorly understood.

Mobile plant microRNAs allow communication within and between organisms.

Plant microRNAs (miRNAs) are small regulatory RNAs that are encoded by endogenous miRNA genes and regulate gene expression through gene silencing, by inducing degradation of their target messenger RNA or by inhibiting its translation. Some miRNAs are mobile molecules inside the plant, and increasing experimental evidence has demonstrated that miRNAs represent molecules that are exchanged between plants, their pathogens, and parasitic plants. It has also been shown that miRNAs are secreted into the external growing medium and that these miRNAs regulate gene expression and the phenotype of nearby receiving plants, thus defining a new concept in plant communication.

Exogenous miRNAs induce post-transcriptional gene silencing in plants.

Plants seem to take up exogenous RNA that was artificially designed to target specific genes, followed by activation of the RNA interference (RNAi) machinery. It is, however, not known whether plants use RNAs themselves as signalling molecules in plant-to-plant communication, other than evidence that an exchange of small RNAs occurs between parasitic plants and their hosts. Exogenous RNAs from the environment, if taken up by some living organisms, can indeed induce RNAi.

Targeted knockout of the gene OsHOL1 removes methyl iodide emissions from rice plants.

Iodine deficiency represents a public health problem worldwide. To increase the amount of iodine in the diet, biofortification strategies of plants have been tried. They rely on the exogenous administration of iodine to increase its absorption and accumulation.

Evidences for a Nutritional Role of Iodine in Plants.

Little is known about the role of iodine in plant physiology. We evaluated the impact of low concentrations of iodine on the phenotype, transcriptome and proteome of . Our experiments showed that removal of iodine from the nutrition solution compromises plant growth, and restoring it in micromolar concentrations is beneficial for biomass accumulation and leads to early flowering.