GROWTH, YIELD AND FATTY ACIDS RESPONSE OF OENOTHERA BIENNIS TO WATER STRESS AND POTASSIUM FERTILIZER APPLICATION

Objective: The objective of this research was to study the effects of water stress treatments (40, 60, and 80 % available soil moisture, ASM) and/or potassium application (0, 0.4 and 0.8 g/pot) on growth parameters, yield and fatty acids content and composition of Oenothera biennis under greenhouse conditions.Methods: A two years pot experiment was conducted on Oenothera biennis under Egypt conditions in 2013/2014 and 2014/2015 seasons. Growth, seed yield (g/plant) and seed fixed oil content recorded at the first and second seasons. The fatty acid profile of total lipids extracted from Oenothera biennis was determined by Gas-liquid chromatography (GLC) analysis.Results: Growth characteristics (plant height, the number of branches, the number of capsules/plant and dry weights of the whole plant, root, and straw), seed yield (g/plant) and oil yield in two seasons were significantly decreased with the rise in water stress levels. Oil % was stimulated in response to water stress. Application of potassium counteracted the adverse effects of water stress. The maximum growth, seed yield and oil yield were obtained from plants irrigated with 80 % available soil moisture (ASM) plus potassium (0.8 g/pot). On the contrary, supplying plants with a water level of 40 % ASM and with potassium (0.8 g/pot) or (0.4 g/pot) gave the best result for the oil percentage in the first and second seasons, respectively. In respect to fatty acids profile, the percentage of C16:0, C18:1n9 and C22:0 acids were increased with increasing water stress while a reverse response was observed in C18:0, C18:2n6, C20:0, C18:3n6 and C20:1n9 acids. K application attenuated oil composition, where it led to a slight increase in C18:2n6 and C20:0 acids while decreased the percentages of C16:0, C18:1n9, C22:0 acids C18:0, C18:3n6 and C20:1n9 acids. Potassium rates plus 60 % ASM increased C18:0 and C18:1n9 acids while K application with both of 60 % ASM and 40 % ASM increased C18:2n6 and C20:0 acids. The C22:0 acids increased under the interaction of all irrigation treatments with (0.4 g/pot) dose of K. However, C16:0 acids increased as a result of 80 % ASM treatment with the different potassium rates. This study demonstrated the beneficial effects of K application to alleviating the adverse effects of water stress on Oenothera plants.Conclusion: Increasing irrigation levels increased the plant height, the number of branches, the number of capsules/plant, seed yield and dry weights of the whole plant, root, and straw of Oenothera biennis and the optimum irrigation level for the highest yields of these variables was 80 % ASM. Whereas, oil % decreased with increasing irrigation levels and the optimum irrigation level for the highest oil % was 40 % ASM. However, for the oil yield from plants that received 80 % ASM produced more oil yield than plants received 60 % or 40 % ASM. Application of potassium counteracted the adverse effects of water stress. Potassium fertilizer increased plant height, the number of branches, the number of capsules/plant, seed yield and dry weights of the whole plant, root, and straw of Oenothera biennis. Application of potassium could be a practical approach for enhancing the oil accumulation in Oenothera biennis. The current study provided important information about the qualitative and quantitative changes in the fatty acids profile of Oenothera biennis in relation to potassium application under water stress conditions.Keywords: Fatty acids, Oenothera biennis, Potassium fertilizer, Water stres

A Novel Role of the L-Type Calcium Channel α1D Subunit as a Gatekeeper for Intracellular Zinc Signaling: Zinc Wave

Recent studies have shown that zinc ion (Zn) can behave as an intracellular signaling molecule. We previously demonstrated that mast cells stimulated through the high-affinity IgE receptor (FcεRI) rapidly release intracellular Zn from the endoplasmic reticulum (ER), and we named this phenomenon the “Zn wave”. However, the molecules responsible for releasing Zn and the roles of the Zn wave were elusive. Here we identified the pore-forming α1 subunit of the Cav1.3 (α1D) L-type calcium channel (LTCC) as the gatekeeper for the Zn wave. LTCC antagonists inhibited the Zn wave, and an agonist was sufficient to induce it. Notably, α1D was mainly localized to the ER rather than the plasma membrane in mast cells, and the Zn wave was impaired by α1D knockdown. We further found that the LTCC-mediated Zn wave positively controlled cytokine gene induction by enhancing the DNA-binding activity of NF- κB. Consistent with this finding, LTCC antagonists inhibited the cytokine-mediated delayed-type allergic reaction in mice without affecting the immediate-type allergic reaction. These findings indicated that the LTCC α1D subunit located on the ER membrane has a novel function as a gatekeeper for the Zn wave, which is involved in regulating NF-κB signaling and the delayed-type allergic reaction

Nigella sativa (Black Cumin) Seed Extract Alleviates Symptoms of Allergic Diarrhea in Mice, Involving Opioid Receptors

The incidence of food hypersensitivity and food allergies is on the rise and new treatment approaches are needed. We investigated whether N. sativa, one of its components, thymoquinone, or synthetic opioid receptor (OR)-agonists can alleviate food allergy. Hence, ovalbumin (OVA) -sensitized BALB/c-mice were pre-treated either with a hexanic N. sativa seed extract, thymoquinone, kappa- (U50'4889) or mu-OR-agonists (DAMGO) and subsequently challenged intra-gastrically with OVA. All 4 treatments significantly decreased clinical scores of OVA-induced diarrhea. N. sativa seed extract, thymoquinone, and U50'488 also decreased intestinal mast cell numbers and plasma mouse mast cell protease-1 (MMCP-1). DAMGO, in contrast, had no effect on mast cell parameters but decreased IFNγ, IL-4, IL-5, and IL-10 concentration after ex vivo re-stimulation of mesenteric lymphocytes. The effects on allergy symptoms were reversible by OR-antagonist pre-treatment, whereas most of the effects on immunological parameter were not. We demonstrate that N. sativa seed extract significantly improves symptoms and immune parameters in murine OVA-induced allergic diarrhea; this effect is at least partially mediated by thymoquinone. ORs may also be involved and could be a new target for intestinal allergy symptom alleviation. N. sativa seed extract seems to be a promising candidate for nutritional interventions in humans with food allergy

Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings

Considerable interest has been shown in the ability of caloric restriction (CR) to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE) consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF) consists of two interchanging days; one day, subjects may consume food ad libitum (sometimes equaling twice the normal intake); on the other day, food is reduced or withheld altogether. Dietary restriction (DR) - restriction of one or more components of intake (typically macronutrients) with minimal to no reduction in total caloric intake - is another alternative to CR. Many religions incorporate one or more forms of food restriction. The following religious fasting periods are featured in this review: 1) Islamic Ramadan; 2) the three principal fasting periods of Greek Orthodox Christianity (Nativity, Lent, and the Assumption); and 3) the Biblical-based Daniel Fast. This review provides a summary of the current state of knowledge related to CR and DR. A specific section is provided that illustrates related work pertaining to religious forms of food restriction. Where available, studies involving both humans and animals are presented. The review includes suggestions for future research pertaining to the topics of discussion

Identification of Genes That Promote or Antagonize Somatic Homolog Pairing Using a High-Throughput FISH–Based Screen

The pairing of homologous chromosomes is a fundamental feature of the meiotic cell. In addition, a number of species exhibit homolog pairing in nonmeiotic, somatic cells as well, with evidence for its impact on both gene regulation and double-strand break (DSB) repair. An extreme example of somatic pairing can be observed in Drosophila melanogaster, where homologous chromosomes remain aligned throughout most of development. However, our understanding of the mechanism of somatic homolog pairing remains unclear, as only a few genes have been implicated in this process. In this study, we introduce a novel high-throughput fluorescent in situ hybridization (FISH) technology that enabled us to conduct a genome-wide RNAi screen for factors involved in the robust somatic pairing observed in Drosophila. We identified both candidate “pairing promoting genes” and candidate “anti-pairing genes,” providing evidence that pairing is a dynamic process that can be both enhanced and antagonized. Many of the genes found to be important for promoting pairing are highly enriched for functions associated with mitotic cell division, suggesting a genetic framework for a long-standing link between chromosome dynamics during mitosis and nuclear organization during interphase. In contrast, several of the candidate anti-pairing genes have known interphase functions associated with S-phase progression, DNA replication, and chromatin compaction, including several components of the condensin II complex. In combination with a variety of secondary assays, these results provide insights into the mechanism and dynamics of somatic pairing

Synergism between particle-based multiplexing and microfluidics technologies may bring diagnostics closer to the patient

In the field of medical diagnostics there is a growing need for inexpensive, accurate, and quick high-throughput assays. On the one hand, recent progress in microfluidics technologies is expected to strongly support the development of miniaturized analytical devices, which will speed up (bio)analytical assays. On the other hand, a higher throughput can be obtained by the simultaneous screening of one sample for multiple targets (multiplexing) by means of encoded particle-based assays. Multiplexing at the macro level is now common in research labs and is expected to become part of clinical diagnostics. This review aims to debate on the “added value” we can expect from (bio)analysis with particles in microfluidic devices. Technologies to (a) decode, (b) analyze, and (c) manipulate the particles are described. Special emphasis is placed on the challenges of integrating currently existing detection platforms for encoded microparticles into microdevices and on promising microtechnologies that could be used to down-scale the detection units in order to obtain compact miniaturized particle-based multiplexing platforms