Salicylic Acid Modulates Antioxidant System,Defense Metabolites,and Expression of Salt Transporter Genes in Pisum sativum Under Salinity Stress

At present plants continuously exposed to salinity stress due to the challenging environment that has reduced the crop growth and productivity worldwide. Application of phytohormones by using seed priming method emerges as one of the most reliable and cost effective to alleviate the toxic effect of salinity stress. In this study, we evaluate the effect of seed-primed salicylic acid (SA) to reduce the adverse effect of different salt concentrations (0, 100, 200, and 300 mM NaCl) in pea (Pisum sativum L.) seedlings. After seedling emergence, percent seed germination was calculated; however, after 60 days; plants were sampled for studying the growth and photosynthetic traits, lipid peroxidation level, antioxidant activities, ions accumulation, and its sequestration. The results depicted that salinity treatments hampered overall growth performance and induced oxidative stress in a dose-dependent manner. Salinity also has negatively influence on ion accumulation as Na⁺ ion increased while K⁺ ion decreased. On the other hand, seed priming with SA significantly reduced the salinity-induced effects on the overall performance of plants, including growth and photosynthetic attributes. SA alleviated the adverse effect of salinity even at higher salinity level by inducing enzymatic and non-enzymatic antioxidant systems, soluble sugars, and proline accumulation, and regulating ion homeostasis along with up-regulation of Na⁺/H⁺ antiporters (SOS1 and NHX1). Thus, seed priming with SA shows a comprehensive role in mitigation of salinity stress and can be used as a model for promising salinity tolerant cultivation.

     

In vitro induction, screening and detection of high essential oil yielding somaclones in turmeric (Curcuma longa L.)

Leaf of turmeric contains an essential oil used extensively in perfumery, pharmaceuticals and aromatherapy. Five somaclones were induced in turmeric on MS media with varying amounts of plant growth regulators. All somaclones were subsequently transferred to the field. Essential oil was extracted from leaves of in vitro and ex vitro grown plants and subjected to quantitative and qualitative evaluation. A positive correlation was established between the leaf oil content and oil constituent of in vitro grown and field transferred somaclones. Somaclones (C2, C4, C5) containing 0.16–0.18 % oil in vitro retained normal oil content (0.48–0.5 %) in the field. Similarly in vitro grown somaclones C3 and C7 with 0.36 and 0.25 % oil content retained proportionately increased oil yields of 1 % and 0.76 under ex vitro condition. GC–MS analysis of the oil revealed similar spectrum of constituents both among in vitro and ex vitro grown plants with alpha-phellandrene as major one. Thus the novel method of in vitro screening could be applied for rapid identification of high essential oil yielding turmeric genotypes thereby reducing labour, cost and time required in conventional ex vitro screening of somaclones.     

Capping motifs stabilize the leucine‐rich repeat protein PP32 and rigidify adjacent repeats

Capping motifs are found to flank most β‐strand‐containing repeat proteins. To better understand the roles of these capping motifs in organizing structure and stability, we carried out folding and solution NMR studies on the leucine‐rich repeat (LRR) domain of PP32, which is composed of five tandem LRR, capped by α‐helical and β‐hairpin motifs on the N‐ and C‐termini. We were able to purify PP32 constructs lacking either cap and containing destabilizing substitutions. Removing the C‐cap results in complete unfolding of PP32. Removing the N‐cap has a much less severe effect, decreasing stability but retaining much of its secondary structure. In contrast, the dynamics and tertiary structure of the first two repeats are significantly perturbed, based on ¹H‐¹⁵N relaxation studies, chemical shift perturbations, and residual dipolar couplings. However, more distal repeats (3 to C‐cap) retain their native tertiary structure. In this regard, the N‐cap drives the folding of adjacent repeats from what appears to be a molten‐globule‐like state. This interpretation is supported by extensive analysis using core packing substitutions in the full‐length and N‐cap‐truncated PP32. This work highlights the importance of caps to the stability and structural integrity of β‐strand‐containing LRR proteins, and emphasizes the different contributions of the N‐ and C‐terminal caps.     

The Cardiopulmonary Effects of Ambient Air Pollution and Mechanistic Pathways: A Comparative Hierarchical Pathway Analysis

Previous studies have investigated the associations between exposure to ambient air pollution and biomarkers of physiological pathways, yet little has been done on the comparison across biomarkers of different pathways to establish the temporal pattern of biological response. In the current study, we aim to compare the relative temporal patterns in responses of candidate pathways to different pollutants. Four biomarkers of pulmonary inflammation and oxidative stress, five biomarkers of systemic inflammation and oxidative stress, ten parameters of autonomic function, and three biomarkers of hemostasis were repeatedly measured in 125 young adults, along with daily concentrations of ambient CO, PM_2.5, NO₂, SO₂, EC, OC, and sulfate, before, during, and after the Beijing Olympics. We used a two-stage modeling approach, including Stage I models to estimate the association between each biomarker and pollutant over each of 7 lags, and Stage II mixed-effect models to describe temporal patterns in the associations when grouping the biomarkers into the four physiological pathways. Our results show that candidate pathway groupings of biomarkers explained a significant amount of variation in the associations for each pollutant, and the temporal patterns of the biomarker-pollutant-lag associations varied across candidate pathways (p<0.0001) and were not linear (from lag 0 to lag 3: p = 0.0629, from lag 3 to lag 6: p = 0.0005). These findings suggest that, among this healthy young adult population, the pulmonary inflammation and oxidative stress pathway is the first to respond to ambient air pollution exposure (within 24 hours) and the hemostasis pathway responds gradually over a 2–3 day period. The initial pulmonary response may contribute to the more gradual systemic changes that likely ultimately involve the cardiovascular system.     

Binding of gemini bisbenzimidazole drugs with human telomeric G-quadruplex dimers: effect of the spacer in the design of potent telomerase inhibitors

The study of anticancer agents that act via stabilization of telomeric G-quadruplex DNA (G4DNA) is important because such agents often inhibit telomerase activity. Several types of G4DNA binding ligands are known. In these studies, the target structures often involve a single G4 DNA unit formed by short DNA telomeric sequences. However, the 3'-terminal single-stranded human telomeric DNA can form higher-order structures by clustering consecutive quadruplex units (dimers or n-mers). Herein, we present new synthetic gemini (twin) bisbenzimidazole ligands, in which the oligo-oxyethylene spacers join the two bisbenzimidazole units for the recognition of both monomeric and dimeric G4DNA, derived from d(T2AG3)4 and d(T2AG3)8 human telomeric DNA, respectively. The spacer between the two bisbenzimidazoles in the geminis plays a critical role in the G4DNA stability. We report here (i) synthesis of new effective gemini anticancer agents that are selectively more toxic towards the cancer cells than the corresponding normal cells; (ii) formation and characterization of G4DNA dimers in solution as well as computational construction of the dimeric G4DNA structures. The gemini ligands direct the folding of the single-stranded DNA into an unusually stable parallel-stranded G4DNA when it was formed in presence of the ligands in KCl solution and the gemini ligands show spacer length dependent potent telomerase inhibition properties.     

ApoTome to visualize E-cadherin and p63 expression in oral pre-cancer

Precise histopathological localization of E-cadherin and p63 is of immense importance in understanding the integrity of oral mucosal stratified epithelium in normal and diseased conditions. Necessarily immunohistochemical imaging should have minimum bleaching impact on the dyes and ability to produce clear and crisp images. Here ApoTome provides an alternative with metal halide light source and structured illumination under the assistance of grids, along with integrated image processing modality to generate crisp images with digital interface. The current study demonstrates the applicability of such microscopic system in capturing fluorescence images of immunohistochemical sections of normal and precancerous biopsies in respect to the expression of p63 and E-cadherin in the epithelial cells. The ApoTome images localize the nuclear and membranous expressions of p63 and E-cadherin, respectively, with remarkable specificity. The findings on E-cadherin expression have enormous diagnostic significance as these images clearly differentiate the early and advanced stages of oral submucous fibrosis based on their cytoplasmic and membranous location. Thus, this study clearly depicts a remarkable performance of ApoTome with diagnostic significance.     

JAM-A is present in mammalian spermatozoa where it is essential for normal motility

Junctional adhesion molecules (JAMs) that are expressed in endothelial and epithelial cells and function in tight junction assembly, also perform important roles in testis where the closely-related JAM-A, JAM-B, and JAM-C are found. Disruption of murine Jam-B and Jam-C has varying effects on sperm development and function; however, deletion of Jam-A has not yet been studied. Here we show for the first time that in addition to expression in the Sertoli-Sertoli tight junctions in the seminiferous tubules, the ∼ 32 kDa murine JAM-A is present in elongated spermatids and in the plasma membrane of the head and flagellum of sperm. Deletion of Jam-A, using the gene trap technology, results in flagellar defects at the ultrastructural level. In Jam-A-deficient mice, which have reduced litter size, both progressive and hyperactived motility are significantly affected (P < 0.0001) before and, more severely, after capacitation. The findings show that JAM-A is involved in sperm tail formation and is essential for normal motility, which may occur via its signal transduction and protein phosphorylation properties. Detection of JAM-A in human sperm proteins indicates that its role may be conserved in sperm motility and that JAM-A may be a candidate gene for the analysis of idiopathic sperm motility defects resulting in male subfertility in the human population.     

Biomechanics of leg deformity treatment

At pre-school age, there is a possibility to treat severe varosity and/or valgosity of legs by orthoses. The three points force effect of the orthosis partially corrects the pathologic defect of the leg. If the orthosis is intermittently used for a long time the correction is permanent. Step by step correction of bone deformities are based on remodelling of growth epiphyses and bones that are caused by orthotic bending pre-stressing. According to Hüter-Volkmann's law, the oblique loading regulates the growth of epiphyseal plates of long bone into the direction of the pressure result and the bone remodelling process is started: it means that the bone grows at the tensile part of growth epiphyses more quickly than at pressure one and gradually eliminates the varosity and/or valgosity defect. The knowledge of stress values for starting of the bone remodelling process is principal for clinical praxis. The values of pre-stressing cannot be increased by starting the remodelling process from the ethical point of view but it can be judged on its starting according to the success of the treatment. The aim of this article is to study the bone, ligament stress state and deformations of successful treatment. Method and calculation algorithm of stress state and deformation that are necessary for the starting of the remodelling process at the knee region were verified on a group of eight patients that were fitted by orthoses with bending pre-stressing. The space models of the knee, femur and tibia were composed with the help of X-ray, CT and MRI scan. The calculation algorithm was implemented on a PC and the program can be easily applied at clinical praxis.     

Requirement offlex (femalelethal onX) in the development of the female germ line ofDrosophila melanogaster

Drosophila melanogaster females homozygous forflex, an X-linked recessive mutation, do not survive. Hemizygous males are unaffected. Homozygous embryos appear to lack SXL, the product of theSex-lethal (Sxl) gene, apparently as a result of disruption ofSxl splicing. It is known that bothSxl and its somatic splicing regulators [snf andfl(2)d] also function in the development of the female germ line. For this reason, we investigated the role offlex in the germ line by generatingflex/flex clones inflex/+ females. Females carrying such clones in their germ lines do not lay eggs whereas females carryingflex+ eggs lay viable eggs. Additionally, DAPI staining of ovarioles showed that diploid germ cells that are homozygous mutant forflex do not complete oogenesis. These results indicate that theflex+ gene product may be required for the development of the female germ line.