Anthocyanin management in fruits by fertilization

Anthocyanins are water-soluble vacuolar plant pigments that are mainly synthesized in epidermal layers and the flesh of fruits such as apples, cherries, grapes, and other berries. Because of their attractive red to purple coloration and their health-promoting potential, anthocyanins are significant determinants for the quality and market value of fruits and fruit-derived products. In crops, anthocyanin accumulation in leaves can be caused by nutrient deficiency which is usually ascribed to insufficient nitrogen or phosphorus fertilization. However, it is a little-known fact that the plant’s nutrient status also impacts anthocyanin synthesis in fruits. Hence, strategic nutrient supply can be a powerful tool to modify the anthocyanin content and consequently the quality and market value of important agricultural commodities. Here we summarize the current knowledge of the influence of plant nutrients on anthocyanin synthesis in fruits of major global market value and discuss the underlying cellular processes that integrate nutrient signaling with fruit anthocyanin formation. It is highlighted that fertilization that is finely tuned in amount and timing has the potential to positively influence the fruit quality by regulating anthocyanin levels. We outline new approaches to enrich plant based foods with health-promoting anthocyanins

Integrative multi‐omics analyses of date palm (Phoenix dactylifera) roots and leaves reveal how the halophyte land plant copes with sea water

Date palm (Phoenix dactylifera L.) is able to grow and complete its life cycle while being rooted in highly saline soils. Which of the many well-known salt-tolerance strategies are combined to fine-tune this remarkable resilience is unknown. The precise location, whether in the shoot or the root, where these strategies are employed remains uncertain, leaving us unaware of how the various known salt-tolerance mechanisms are integrated to fine-tune this remarkable resilience. To address this shortcoming, we exposed date palm to a salt stress dose equivalent to seawater for up to 4 weeks and applied integrative multi-omics analyses followed by targeted metabolomics, hormone, and ion analyses. Integration of proteomic into transcriptomic data allowed a view beyond simple correlation, revealing a remarkably high degree of convergence between gene expression and protein abundance. This sheds a clear light on the acclimatization mechanisms employed, which depend on reprogramming of protein biosynthesis. For growth in highly saline habitats, date palm effectively combines various salt-tolerance mechanisms found in both halophytes and glycophytes: “avoidance” by efficient sodium and chloride exclusion at the roots, and “acclimation” by osmotic adjustment, reactive oxygen species scavenging in leaves, and remodeling of the ribosome-associated proteome in salt-exposed root cells. Combined efficiently as in P. dactylifera L., these sets of mechanisms seem to explain the palm's excellent salt stress tolerance

Proteome analysis and pH sensitive ratio imaging: Tools to explore the decline in leaf growth under salinity

More than 50% of all irrigated areas are affected by soil salinity. In most saline environments, NaCl is the predominant salt species, whose principle adverse effect in non-resistant plants is growth reduction due to an inhibition of cell division and cell elongation caused by osmotic effects, ion toxicity, and mineral disturbances in plants. Growth reduction was more pronounced in leaves of sensitive genotypes compared to resistant genotypes. While root and shoot Na+ is an adequate parameter to describe uptake and translocation, the apoplastic pH might be a more important trait in order to describe the decline in leaf growth. Using FITC-dextran (50 µM) as a suitable fluorescent dye, a significant apoplastic alkalization of the salt-sensitive Pioneer 3906 and Vicia faba could be shown, whereas this was not valid for the more resistant maize hybrid. The adaptation to salt stress has a strong impact on the leaf proteome. We demonstrate that the activity of expansins was reduced under salt stress especially in the less resistant maize hybrid. In conclusion, the transcript level and the proteome show a higher level of β-expansin in resistant maize cultivars compared to more sensitive cultivars thus may contribute to better growth and improved salt resistance

The green light gap: a window of opportunity for optogenetic control of stomatal movement

Green plants are equipped with photoreceptors that are capable of sensing radiation in the ultraviolet‐to‐blue and the red‐to‐far‐red parts of the light spectrum. However, plant cells are not particularly sensitive to green light (GL), and light which lies within this part of the spectrum does not efficiently trigger the opening of stomatal pores. Here, we discuss the current knowledge of stomatal responses to light, which are either provoked via photosynthetically active radiation or by specific blue light (BL) signaling pathways. The limited impact of GL on stomatal movements provides a unique option to use this light quality to control optogenetic tools. Recently, several of these tools have been optimized for use in plant biological research, either to control gene expression, or to provoke ion fluxes. Initial studies with the BL‐activated potassium channel BLINK1 showed that this tool can speed up stomatal movements. Moreover, the GL‐sensitive anion channel GtACR1 can induce stomatal closure, even at conditions that provoke stomatal opening in wild‐type plants. Given that crop plants in controlled‐environment agriculture and horticulture are often cultivated with artificial light sources (i.e. a combination of blue and red light from light‐emitting diodes), GL signals can be used as a remote‐control signal that controls stomatal transpiration and water consumption

Two Worlds Colliding: The Interplay Between Natural Compounds and Non-Coding Transcripts in Cancer Therapy

Cancer is a devastating disease and has recently become the leading cause of death in western countries, representing an immense public health burden. When it comes to cancer treatment, chemotherapy is one of the main pillars, especially for advanced stage tumors. Over the years, natural compounds have emerged as one of the most valuable resources for new chemotherapies. It is estimated that more than half of the currently used chemotherapeutic agents are derived from natural compounds. Usually, natural compounds are discovered empirically and an important limitation of introducing new anti-cancer natural products is lack of knowledge with regard to their mechanism of action. Recent data has proven that several natural compounds may function via modulating the expression and function of non-coding RNAs (ncRNAs). NcRNAs are a heterogenous class of RNA molecules which are usually not translated into proteins but have an important role in gene expression regulation and are involved in multiple tumorigenic processes, including response/resistance to pharmacotherapy. In this review, we will discuss how natural compounds function via ncRNAs while summarizing the available data regarding their effects on over 15 types of cancer. Moreover, we will critically analyze the current advances and limitations in understanding the way natural compounds exert these health-promoting effects by acting on ncRNAs. Finally, we will propose several hypotheses that may open new avenues and perspectives regarding the interaction between natural compounds and ncRNAs, which could lead to improved natural compound-based therapeutic strategies in cancer.Peer Reviewe

Les Etats baltes et le système européen (1985-2004)

C’est toute la question de la place et de la puissance des “sans puissance” en relations internationales qui est ici posée par l’étude de la diplomatie des Etats baltes après 1991. En effet, ce sont les seules anciennes républiques soviétiques à être devenues membres de l'Union européenne et de l'OTAN en 2004. L'étude de leur place dans le système européen en mutation de l'après Guerre Froide est donc un élément essentiel permettant de définir l'Europe par ses marges. Et ce, au moment où de nouvelles frontières durables semblent apparaitre sur le continent. Cet ouvrage montre comment les systèmes politiques renaissants de l’Estonie, de la Lettonie et de la Lituanie des dernières années de l’URSS ont mis en actes une radicale volonté d’ancrage dans les institutions européennes et atlantiques. Malgré des héritages soviétiques complexes relatifs aux frontières et à la définition du corps citoyen, la politique étrangère a été l’un des objectifs de la transformation. Au même moment, le modèle de sécurité en Europe évolue radicalement, permettant aux diplomaties baltes de s’insérer dans ses interstices et, par là, de contribuer à sa modification structurelle. Cette intéraction entre mutations internes et insertions dans le système européen apporte une illustration concrète du fait qu’il fallait “être Européens, pour le devenir”

Under salt stress guard cells rewire ion transport and abscisic acid signaling

Soil salinity is an increasingly global problem which hampers plant growth and crop yield. Plant productivity depends on optimal water-use efficiency and photosynthetic capacity balanced by stomatal conductance. Whether and how stomatal behavior contributes to salt sensitivity or tolerance is currently unknown. This work identifies guard cell-specific signaling networks exerted by a salt-sensitive and salt-tolerant plant under ionic and osmotic stress conditions accompanied by increasing NaCl loads. We challenged soil-grown Arabidopsis thaliana and Thellungiella salsuginea plants with short- and long-term salinity stress and monitored genome-wide gene expression and signals of guard cells that determine their function. Arabidopsis plants suffered from both salt regimes and showed reduced stomatal conductance while Thellungiella displayed no obvious stress symptoms. The salt-dependent gene expression changes of guard cells supported the ability of the halophyte to maintain high potassium to sodium ratios and to attenuate the abscisic acid (ABA) signaling pathway which the glycophyte kept activated despite fading ABA concentrations. Our study shows that salinity stress and even the different tolerances are manifested on a single cell level. Halophytic guard cells are less sensitive than glycophytic guard cells, providing opportunities to manipulate stomatal behavior and improve plant productivity