A soybean (<Emphasis Type="Italic">Glycine max</Emphasis>) polyubiquitin promoter gives strong constitutive expression in transgenic soybean

The success of plant genetic transformation relies greatly on the strength and specificity of the promoters used to drive genes of interest. In this study, we analyzed gfp gene expression mediated by a polyubiquitin promoter (Gmubi) from soybean (Glycine max) in stably transformed soybean tissues. Strong GFP expression was observed in stably transformed proliferative embryogenic tissues. In whole transgenic plants, GFP expression was observed in root tips, main and lateral roots, cotyledons and plumules in young plants as well as in leaf veins, petioles, flower petals, pollen, pods and developing seeds in mature plants. GFP expression was localized mainly in epidermal cells, leaf mesophyll, procambium and vascular tissues. Introduction of an intron-less version of the Gmubi promoter (Gmupri) displayed almost the same GFP expression pattern albeit at lower intensities. The Gmubi promoter showed high levels of constitutive expression and represents an alternative to viral promoters for driving gene expression in soybean.     

Modulation of plasma membrane lipid profile and microdomains by H2O2 in Saccharomyces cerevisiae

In Saccharomyces cerevisiae, the rate of hydrogen peroxide (H₂O₂) diffusion through the plasma membrane decreases during adaptation to H₂O₂ by a still unknown mechanism. Here, adaptation to H₂O₂ was observed to modulate rapidly the expression of genes coding for enzymes involved in ergosterol and lipid metabolism. Adaptation to H₂O₂ also alters plasma membrane lipid composition. The main changes were the following: (a) there was a decrease in oleic acid (30%) and in the ratio between unsaturated and saturated long-chain fatty acids; (b) the phosphatidylcholine:phosphatidylethanolamine ratio increased threefold; (c) sterol levels were unaltered but there was an increased heterogeneity of sterol-rich microdomains and increased ordered domains; (d) the levels of the sterol precursor squalene increased twofold, in agreement with ERG1 gene down-regulation; and (e) C26:0 became the major very long chain fatty acid owing to an 80% decrease in 2-hydroxy-C26:0 levels and a 50% decrease in C20:0 levels, probably related to the down-regulation of fatty acid elongation (FAS1, FEN1, SUR4) and ceramide synthase (LIP1, LAC1) genes. Therefore, H₂O₂ leads to a reorganization of the plasma membrane microdomains, which may explain the lower permeability to H₂O₂, and emerges as an important regulator of lipid metabolism and plasma membrane lipid composition.     

Growth and nutrient absorption of two submerged aquatic macrophytes in mesocosms, for reinsertion in a eutrophicated shallow lake

Aquatic macrophytes play a central role in preserving the ecological equilibrium of shallow lakes and in the restoration of eutrophic lakes that have switched to phytoplankton-dominated turbid water. Massaciuccoli Lake, a shallow lake located along the Tuscan coast in Italy, has shown a constant and progressive simplification of the submerged plant community, for anthropogenic reasons, leading, in recent years, to turbid water. The growth and nutrient absorption capability of two macrophyte species, Myriophyllum verticillatum L. and Elodea canadensis Michaux, in the lake was investigated, with the prospect of a future lake restoration programme centred on their replacement. Mesocosm experiments were conducted to monitor the plant growth and nutrient (NO₂⁻, NO₃⁻, NH₄⁺, Ntot, PO₄³⁻, Ptot) content in the plant dry matter and water at the beginning and at the end of the trial. Bacterial activity was analysed in the water in order to verify the possible nutrient absorption contribution by organisms other than plants. Both M. verticillatum and E. canadensis showed satisfactory growth and nutrient reduction in the water body. Moreover, their different growth patterns suggested that optimal replacement can be performed with their introduction in two steps, starting with M. verticillatum, which shows the best capacity to colonise the aquatic environment, due to its tendency towards lengthening.     

Increased FGF-2 secretion and ability to support neurite outgrowth by astrocytes cultured on polyamide nanofibrillar matrices

An electrospun nonwoven matrix of polyamide nanofibers was employed as a new model for the capillary basement membrane at the blood-brain barrier (BBB). The basement membrane separates astrocytes from endothelial cells and is associated with growth factors, such as fibroblast growth factor-2 (FGF-2). FGF-2 is produced by astrocytes and induces specialized functions in endothelial cells, but also has actions on astrocytes. To investigate potential autocrine actions of FGF-2 at the BBB, astrocytes were cultured on unmodified nanofibers or nanofibers covalently modified with FGF-2. The former assumed an in vivo-like stellate morphology that was enhanced in the presence of cross-linked FGF-2. Furthermore, astrocyte monolayers established on unmodified nanofibers were more permissive for neurite outgrowth when cultured with an overlay of neurons than similar monolayers established on standard tissue culture surfaces, while astrocytes cultured on FGF-2-modifed nanofibers were yet more permissive. The observed differences were due in part to progressively increasing amounts of FGF-2 secreted by the astrocytes into the medium; hence FGF-2 increases its own expression in astrocytes to modulate astrocyte–neuron interactions. Soluble FGF-2 was unable to replicate the effects of cross-linked FGF-2. Nanofibers alone up-regulated FGF-2, albeit to a lesser extent than nanofibers covalently modified with FGF-2. These results underscore the importance of both surface topography and growth factor presentation on cellular function. Moreover, these results indicate that FGF-2-modified nanofibrillar scaffolds may demonstrate utility in tissue engineering applications for replacement and regeneration of lost tissue following central nervous system (CNS) injury or disease.     

Discovery of novel lipophilic inhibitors of OXA-10 enzyme (class D β-lactamase) by screening amino analogs and homologs of citrate and isocitrate

Aminocitrate (and homolog) derivatives have been prepared by bis-alkylation of glycinate Schiff bases with bromoacetates (and ethyl acrylate), followed by N-acylation and esters (partial or complete) deprotection. Aminoisocitrate was similarly obtained by mono-alkylation with diethyl fumarate. Evaluation against representative β-lactamases revealed that the free acid derivatives are modest inhibitors of class A enzymes, whilst their benzyl esters showed a good inhibition of OXA-10 (class D enzyme). A docking experiment featured hydrophobic interactions in the active site.     

Oat5 and NaDC1 Protein Abundance in Kidney and Urine After Renal Ischemic Reperfusion Injury

The aim of this study was to evaluate the abundance of the organic anion transporter 5 (Oat5) and the sodium-dicarboxylate cotransporter 1 (NaDC1) in kidney and urine after renal ischemic reperfusion injury. Renal injury was induced in male Wistar rats by occlusion of both renal pedicles for 0 (Group Sham), 5 (Group I5R60), or 60 (Group I60R60) min. The studies were performed after 60 min of reperfusion. The expression of Oat5 and NaDC1 was evaluated by IHC and Western blotting. Oat5 and NaDC1 abundance and alkaline phosphatase activity (AP) were assayed in urine. A decreased expression in renal homogenates and apical membranes and an increase in urinary excretion of Oat5 and NaDC1 were observed in I60R60 rats, as well as alterations of other widely used parameters for renal dysfunction and injury (plasma creatinine, urinary AP activity, kidney weight, histological lesions). In contrast, in the I5R60 group, only an increase in urinary excretion of Oat5 and mild histopathological damage was detected. This is the first study on Oat5 and NaDC1 detection in urine. These results suggest that urinary excretion of Oat5 might be an early indicator of renal dysfunction, which is useful for detection of even minor alterations in renal structural and functional integrity. (J Histochem Cytochem 57:17–27, 2009)     

Chimpanzee nest distribution and site reuse in a dry habitat: implications for early hominin ranging

This paper reports on a 20-month study of chimpanzee nesting patterns in Issa, Ugalla, western Tanzania. Ugalla is one of the driest, most open, and seasonal habitats where chimpanzees are found. The methods used were ethoarchaeological, as the chimpanzees were not habituated and behavioural observations were rare. Systematic data on the spatial and temporal distribution of nests are presented. Places with no nests at the beginning of the study, despite being suitable for nesting, were used as controls. Similar to other chimpanzee study sites, nests were highly concentrated in some parts of the landscape. Issa chimpanzees preferred to nest on slopes. They extensively used the woodland vegetation type of their habitat for nesting throughout the annual cycle. Ninety percent of nest sites were used repeatedly throughout the study period, but none of the control places had nests during this period. The results indicate that chimpanzees ranged more widely during the dry season, when food abundance was lowest, food was available mainly in open vegetation types, and when drinking water was restricted to a few sources. Early hominins in similar habitats may have followed the ranging strategy of Issa chimpanzees. As with a previous study, the distribution of nests was spatially similar to archaeological distributions in early hominin sites. Hominin topography and vegetation type preferences may be misrepresented in the archaeological record. Nest sites may have been the antecedents of carcass processing sites.