Chemical structures of selective blockers of TASK channels contain aromatic groups and amide bonds. Using this rationale, we designed and synthesized a series of compounds based on 3-benzamidobenzoic ...acid. These compounds block TASK-1 channels by binding to the central cavity. The most active compound is 3-benzoylamino-N-(2-ethyl-phenyl)-benzamide or F3, blocking TASK-1 with an IC50 of 148 nM, showing a reduced inhibition of TASK-3 channels and not a significant effect on different K+ channels. We identified putative F3-binding sites in the TASK-1 channel by molecular modeling studies. Mutation of seven residues to A (I118A, L122A, F125A, Q126A, L232A, I235A, and L239A) markedly decreased the F3-induced inhibition of TASK-1 channels, consistent with the molecular modeling predictions. F3 blocks cell proliferation and viability in the MCF-7 cancer cell line but not in TASK-1 knockdown MCF-7 cells, indicating that it is acting in TASK-1 channels. These results indicated that TASK-1 is necessary to drive proliferation in the MCF-7 cancer cell line.
Rational drug design targeting ion channels is an exciting and always evolving research field. New medicinal chemistry strategies are being implemented to explore the wild chemical space and unravel ...the molecular basis of the ion channels modulators binding mechanisms. TASK channels belong to the two-pore domain potassium channel family and are modulated by extracellular acidosis. They are extensively distributed along the cardiovascular and central nervous systems, and their expression is up- and downregulated in different cancer types, which makes them an attractive therapeutic target. However, TASK channels remain unexplored, and drugs designed to target these channels are poorly selective. Here, we review TASK channels properties and their known blockers and activators, considering the new challenges in ion channels drug design and focusing on the implementation of computational methodologies in the drug discovery process.
α-Synuclein (αSyn) species can be detected in synaptic boutons, where they play a crucial role in the pathogenesis of Parkinson's Disease (PD). However, the effects of intracellular αSyn species on ...synaptic transmission have not been thoroughly studied. Here, using patch-clamp recordings in hippocampal neurons, we report that αSyn oligomers (αSynO), intracellularly delivered through the patch electrode, produced a fast and potent effect on synaptic transmission, causing a substantial increase in the frequency, amplitude and transferred charge of spontaneous synaptic currents. We also found an increase in the frequency of miniature synaptic currents, suggesting an effect located at the presynaptic site of the synapsis. Furthermore, our in silico approximation using docking analysis and molecular dynamics simulations showed an interaction between a previously described small anti-amyloid beta (Aβ) molecule, termed M30 (2-octahydroisoquinolin-2(1H)-ylethanamine), with a central hydrophobic region of αSyn. In line with this finding, our empirical data aimed to obtain oligomerization states with thioflavin T (ThT) and Western blot (WB) indicated that M30 interfered with αSyn aggregation and decreased the formation of higher-molecular-weight species. Furthermore, the effect of αSynO on synaptic physiology was also antagonized by M30, resulting in a decrease in the frequency, amplitude, and charge transferred of synaptic currents. Overall, the present results show an excitatory effect of intracellular αSyn low molecular-weight species, not previously described, that are able to affect synaptic transmission, and the potential of a small neuroactive molecule to interfere with the aggregation process and the synaptic effect of αSyn, suggesting that M30 could be a potential therapeutic strategy for synucleinopathies.
Understanding the function of genes within staple crops will accelerate crop improvement by allowing targeted breeding approaches. Despite their importance, a lack of genomic information and ...resources has hindered the functional characterisation of genes in major crops. The recent release of high-quality reference sequences for these crops underpins a suite of genetic and genomic resources that support basic research and breeding. For wheat, these include gene model annotations, expression atlases and gene networks that provide information about putative function. Sequenced mutant populations, improved transformation protocols and structured natural populations provide rapid methods to study gene function directly. We highlight a case study exemplifying how to integrate these resources. This review provides a helpful guide for plant scientists, especially those expanding into crop research, to capitalise on the discoveries made in
and other plants. This will accelerate the improvement of crops of vital importance for food and nutrition security.
Voltage-gated calcium (Ca
) channels are widely expressed and are essential for the completion of multiple physiological processes. Close regulation of their activity by specific inhibitors and ...agonists become fundamental to understand their role in cellular homeostasis as well as in human tissues and organs. Ca
channels are divided into two groups depending on the membrane potential required to activate them: High-voltage activated (HVA, Ca
1.1-1.4; Ca
2.1-2.3) and Low-voltage activated (LVA, Ca
3.1-3.3). HVA channels are highly expressed in brain (neurons), heart, and adrenal medulla (chromaffin cells), among others, and are also classified into subtypes which can be distinguished using pharmacological approaches. Cone snails are marine gastropods that capture their prey by injecting venom, "conopeptides", which cause paralysis in a few seconds. A subset of conopeptides called conotoxins are relatively small polypeptides, rich in disulfide bonds, that target ion channels, transporters and receptors localized at the neuromuscular system of the animal target. In this review, we describe the structure and properties of conotoxins that selectively block HVA calcium channels. We compare their potency on several HVA channel subtypes, emphasizing neuronal calcium channels. Lastly, we analyze recent advances in the therapeutic use of conotoxins for medical treatments.
Background
Latin American countries are improving childhood cancer care, showing strong commitment to implement the Global Initiative for Childhood Cancer, but there are scant publications of the ...situation at a continental level.
Methods
As part of the International Society of Paediatric Oncology Global Mapping project, delegates of each country participating in the Latin American Society of Pediatric Oncology (SLAOP) and chairs of national pediatric oncology societies and cooperative groups were invited to provide information regarding availability of national pediatric cancer control programs (NPCCP), pediatric oncology laws, pediatric oncology tumor registries, and training programs and support to diagnosis and treatment.
Results
Nineteen of the 20 countries participating in SLAOP responded. National delegates reported nine countries with NPCCP and four of them were launched in the past 5 years. National pediatric tumor registries are available in eight countries, and three provided published survival results. Fellowship programs for training pediatric oncologists are available in 12 countries. National delegates reported that eight countries provide support to most essential diagnosis and treatments and 11 provide partial or minimal support that is supplemented by civil society organizations. Seven countries have a pediatric oncology law. There are three international cooperative groups and four national societies for pediatric oncology.
Conclusion
Despite many challenges, there were dramatic advances in survivorship, access to treatment, and availability of NPCCP in Latin America. Countries with highest social development scores in general provide more complete support and are more likely to have NPCCP, training programs, and reported survival results.
The essential mineral nutrient potassium (K⁺) is the most important inorganic cation for plants and is recognized as a limiting factor for crop yield and quality. Nonetheless, it is only partially ...understood how K⁺ contributes to plant productivity. K⁺ is used as a major active solute to maintain turgor and to drive irreversible and reversible changes in cell volume. K⁺ also plays an important role in numerous metabolic processes, for example, by serving as an essential cofactor of enzymes. Here, we provide evidence for an additional, previously unrecognized role of K⁺ in plant growth. By combining diverse experimental approaches with computational cell simulation, we show that K⁺ circulating in the phloem serves as a decentralized energy storage that can be used to overcome local energy limitations. Posttranslational modification of the phloem-expressed Arabidopsis K⁺ channel AKT2 taps this "potassium battery," which then efficiently assists the plasma membrane H⁺-ATPase in energizing the transmembrane phloem (re) loading processes.
Herein we describe the in situ inhibitory activity of three hybrid films (FL1, FL2, and FL3) against two wild strains of Colletotrichum gloeosporioides and Penicillium digitatum as causal agents of ...rot in Persian limes. The films FL2 and FL3 contained 1.0 and 1.3 % weight/volume Litsea glaucescens essential oil (LgEO) and significantly (p<0.05) delayed rot emergence in Persian limes caused by both pathogens up to 10 days. The physicochemical properties of LgEO and hybrid films were obtained, whereas detailed HPLC profiling revealed that fruit covered with these films significantly (p<0.01) preserved reducing sugars (sucrose, fructose, and glucose), organic acids (citric acid, ascorbic acid, malic acid, and oxalic acid), and flavonoids with nutraceutical activity (hesperidin, eriocitrin, naruritin, neohesperidin, diosmin, vitexin, rutin, and quercetin). This evidence sustains that the composites generated in this investigation improve the shelf life of Persian limes and conserve their nutraceutical content.
Avocadoes are a rich source of nutrients and nutraceuticals that preserve human health. Nevertheless, this fruit is susceptible to phytopathogen infection during the postharvest period causing severe ...economic losses. Herein, we report on the in situ antifungal assessment of biodegradable films impregnated with the essential oil of Cinnamomum verum (CvEO) as natural fungistatic coatings to extend postharvest quality of Hass avocadoes (Persea americana cv. Hass). These coatings were evaluated on fruits previously infected with a native strain of Fusarium verticillioides. The cytotoxic assessment of CvEO on F. verticillioides revealed a minimum inhibitory concentration of 0.3±0.0 g L−1 whereas its chemical profiling showed (E)‐cinnamaldehyde (45.9 %) 1,3,8‐p‐menthatriene (7.9 %) and linalool (6.8 %) as the major bioactive compounds. Four coatings (FC1–FC4) were made using chitosan (1 %) and a diverse quantity of CvEO (0.4–1.3 % w/v). The physicochemical properties demonstrated that the films FC3 and FC4 have the optimal characteristics of a food coating. Avocadoes preserved with the films FC3 and FC4 substantially kept (p<0.01) fruit firmness and the nutraceutical content of infected avocados at least for 21 d. The results of the present investigation suggest that our hybrid materials can conserve basic nutritional parameters such as fiber, protein, reducing sugars, as well as the content of unsaturated fatty acids which are the main nutraceuticals of this fruit.
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