Mycorrhizal colonization impacts on phenolic content and antioxidant properties of artichoke leaves and flower heads two years after field transplant

Greenhouse and field experiments were carried out in order to investigate the influence of mycorrhizal inoculation on total phenolic content (TPC) and antioxidant activity, expressed as antiradical power (ARP), of artichoke (Cynara cardunculus L. var. scolymus F.) leaves and flower heads extracts. The establishment of mycorrhizal symbiosis was monitored in pot and field grown plants, and the persistence of the inoculated AMF in roots after 2 years’ growth in the field was assessed by fungal ITS sequencing. Both in the greenhouse and in the field, marked increases in TPC and ARP were detected in leaves and flower heads of artichoke plants inoculated with the AM fungal species Glomus intraradices, either alone or in mixture with Glomus mosseae. In the field, plants inoculated with Glomus mix showed flower heads ARP content increases of 52.7 and 30.0% in the first and second year, respectively, compared with uninoculated plants. After 2 years’ growth in the field ITS rDNA sequences clustering with those of G. mosseae and G. intraradices were retrieved only from inoculated plant roots. Our data show that mycorrhizal inoculation may represent an efficient and sustainable strategy to improve productivity and enhance plant biosynthesis of secondary metabolites with health promoting activities.     

Unstable steady state operations of substrate inhibited cultures by dissolved oxygen control

Microorganism kinetic growth characterized by substrate inhibition was investigated by means of a continuous stirred tank reactor equipped with a feedback controller of the medium feeding flow rate. The aerobic growth of Pseudomonas sp. OX1 with phenol as carbon/energy source was adopted as a case study to test a new control strategy using dissolved oxygen concentration as a state variable. The controller was successful in steadily operating bioconversion under intrinsically unstable conditions. A simple model of the controlled system was proposed to set the feedback controller. The specific growth rate of Pseudomonas sp. OX1 was successfully described by means of the Haldane model. The regression of the experimental data yielded μ(M)=0.26 h(-1), K(Ph)=5×10(-3)g/L and K(I)=0.2g/L. The biomass-to-substrate fractional yield as a function of the specific growth rate did not change moving from substrate-inhibited to substrate-deficient state. The data was modelled according to the Pirt model: m=1.7×10(-2)g/(gh), Y(X/Ph)(Th)=1.3g/g. The specific growth rates calculated for batch and continuous growth were compared.     

European Union research and innovation perspectives on biotechnology

"Food, Agriculture and Fisheries and Biotechnology" is one of 10 thematic areas in the Cooperation programme of the European Union's 7th Framework Programme for Research, Technological Development and Demonstration Activities (FP7). With a budget of nearly €2 billion for the period 2007-2013, its objective is to foster the development of a European Knowledge-Based Bio-Economy (KBBE) by bringing together science, industry and other stakeholders that produce, manage or otherwise exploit biological resources. Biotechnology plays an important role in addressing social, environmental and economic challenges and it is recognised as a key enabling technology in the transition to a green, low carbon and resource-efficient economy. Biotechnologies for non-health applications have received a considerable attention in FP7 and to date 61 projects on industrial, marine, plant, environmental and emerging biotechnologies have been supported with a contribution of €262.8 million from the European Commission (EC). This article presents an outlook of the research, technological development and demonstration activities in biotechnology currently supported in FP7 within the Cooperation programme, including a brief overview of the policy context.     

Sedimentary evidence for recent increases in production in Tibetan plateau lakes

The Tibetan Plateau is a vast, elevated plateau in Central Asia with an average elevation of over 4,500 m and contains the world’s third largest store of ice. It occupies a climatic transition zone between the Asian monsoons and westerly airflow. As a result of this location, the region is sensitive to changes in climate on timescales of decades to millennia and longer. Long-term data are needed to evaluate climatic changes and their impact on ecosystems, but in areas as remote as the Tibetan Plateau, long-term instrumental records of environmental change are geographically sparse and monitoring has only been undertaken in recent times. Paleolimnological approach might be then one of the few means by which environmental variability can be ascertained at scales that allow comparison with contemporary monitoring data and future model projections. Therefore, a paleolimnological study was undertaken in eight different lakes sampled along a North–South transect across the Tibetan Plateau analysing geochemistry and algal pigment in order to assess longer term variability in the trophic condition of these systems and their potential to reconstruct changes in relation to recent climate evolution and possible human impacts. Chronologies for the last century were based on radiometric techniques (²¹⁰Pb, ²⁴¹Am and ¹³⁷Cs). Results show that inorganic sediment dominates the composition of the cores used in this study. Organic carbon constitutes less than 5% d.w. in all the lake cores, except for Kemen Co core where concentrations up to 14% d.w., are observed. Corg:N ratios are generally in the order of 5–10, indicating that autochthonous algal production is the principal biological source of organic matter. Pigment preservation is generally good throughout the cores from all lakes as shown by the 430:410 nm ratio that is generally around 1.0 or higher. Six out of eight lakes show an increase in primary production in recent times. High pre-1800 AD pigment concentrations were detected only in Qinghai Lake. Since most of the lakes show a similar behaviour in the most recent section of the core, we interpret this as a response to climate and land-use changes that have increased autochthonous production throughout the Tibetan Plateau.     

Nephrocystin-1 Forms a Complex with Polycystin-1 via a Polyproline Motif/SH3 Domain Interaction and Regulates the Apoptotic Response in Mammals

Mutations in PKD1, the gene encoding for the receptor Polycystin-1 (PC-1), cause autosomal dominant polycystic kidney disease (ADPKD). The cytoplasmic C-terminus of PC-1 contains a coiled-coil domain that mediates an interaction with the PKD2 gene product, Polycystin-2 (PC-2). Here we identify a novel domain in the PC-1 C-terminal tail, a polyproline motif mediating an interaction with Src homology domain 3 (SH3). A screen for interactions using the PC-1 C-terminal tail identified the SH3 domain of nephrocystin-1 (NPHP1) as a potential binding partner of PC-1. NPHP1 is the product of a gene that is mutated in a different form of renal cystic disease, nephronophthisis (NPHP). We show that in vitro pull-down assays and NMR structural studies confirmed the interaction between the PC-1 polyproline motif and the NPHP1 SH3 domain. Furthermore, the two full-length proteins interact through these domains; using a recently generated model system allowing us to track endogenous PC-1, we confirm the interaction between the endogenous proteins. Finally, we show that NPHP1 trafficking to cilia does not require PC-1 and that PC-1 may require NPHP1 to regulate resistance to apoptosis, but not to regulate cell cycle progression. In line with this, we find high levels of apoptosis in renal specimens of NPHP patients. Our data uncover a link between two different ciliopathies, ADPKD and NPHP, supporting the notion that common pathogenetic defects, possibly involving de-regulated apoptosis, underlie renal cyst formation.     

Anthropometric and strength variables to predict freestyle performance times in elite master swimmers

The aims of this study were to determine in elite master swimmers of both genders whether, using anthropometric variables and the hand grip strength measure, it was possible to predict freestyle performance time, whether the considered predictors were related similarly to different events (50, 100, 200, 400, 800 m), and whether they were the same in male and female master swimmers. The relationships between performance times and age, body mass, height, arm length, forearm length, forearm muscle volume, and hand grip strength were examined in 135 elite master swimmers. Pearson's simple correlation coefficients were calculated and then prediction equations were developed. Age, height, and hand grip strength were the best predictors in short-distance events, whereas only age and height were predictors in middle- and long-distance events. The corresponding coefficient of determination (R) of performance times were 0.84 in the 50-m event, 0.73 in the 100-m event, 0.75 in the 200-m event, 0.66 in the 400-m event, and 0.63 in the 800-m event. These regression equations were then cross-validated in a control group of 126 nonelite, age-matched swimmers, obtaining significant and good correlations for all distances (range, r = 0.67 and 0.83; p < 0.01), indicating that predictors are valid in an extended sample of master swimmers. Differences between sexes were not found in 50-m event, but were present in all other events. These models might be useful to determine individual performance times by contributing to improving the individual's training program and the selection of master swimmers. Coaches could have better accuracy in determining whether an athlete needs a strength training program in order to optimize performance time.     

Thermal tolerance, acclimatory capacity and vulnerability to global climate change

Despite evidence that organismal distributions are shifting in response to recent climatic warming, we have little information on direct links between species' physiology and vulnerability to climate change. We demonstrate a positive relationship between upper thermal tolerance and its acclimatory ability in a well-defined clade of closely related European diving beetles. We predict that species with the lowest tolerance to high temperatures will be most at risk from the adverse effects of future warming, since they have both low absolute thermal tolerance and poor acclimatory ability. Upper thermal tolerance is also positively related to species' geographical range size, meaning that species most at risk are already the most geographically restricted ones, being endemic to Mediterranean mountain systems. Our findings on the relationship between tolerance and acclimatory ability contrast with results from marine animals, suggesting that generalizations regarding thermal tolerance and responses to future rapid climate change may be premature.     

Magic-factor 1, a partial agonist of Met, induces muscle hypertrophy by protecting myogenic progenitors from apoptosis

Background

Hepatocyte Growth Factor (HGF) is a pleiotropic cytokine of mesenchymal origin that mediates a characteristic array of biological activities including cell proliferation, survival, motility and morphogenesis. Its high affinity receptor, the tyrosine kinase Met, is expressed by a wide range of tissues and can be activated by either paracrine or autocrine stimulation. Adult myogenic precursor cells, the so called satellite cells, express both HGF and Met. Following muscle injury, autocrine HGF-Met stimulation plays a key role in promoting activation and early division of satellite cells, but is shut off in a second phase to allow myogenic differentiation. In culture, HGF stimulation promotes proliferation of muscle precursors thereby inhibiting their differentiation.

Methodology/Principal Findings

Magic-Factor 1 (Met-Activating Genetically Improved Chimeric Factor-1 or Magic-F1) is an HGF-derived, engineered protein that contains two Met-binding domains repeated in tandem. It has a reduced affinity for Met and, in contrast to HGF it elicits activation of the AKT but not the ERK signaling pathway. As a result, Magic-F1 is not mitogenic but conserves the ability to promote cell survival. Here we show that Magic-F1 protects myogenic precursors against apoptosis, thus increasing their fusion ability and enhancing muscular differentiation. Electrotransfer of Magic-F1 gene into adult mice promoted muscular hypertrophy and decreased myocyte apoptosis. Magic-F1 transgenic mice displayed constitutive muscular hypertrophy, improved running performance and accelerated muscle regeneration following injury. Crossing of Magic-F1 transgenic mice with α-sarcoglycan knock-out mice –a mouse model of muscular dystrophy– or adenovirus-mediated Magic-F1 gene delivery resulted in amelioration of the dystrophic phenotype as measured by both anatomical/histological analysis and functional tests.

Conclusions/Significance

Because of these features Magic-F1 represents a novel molecular tool to counteract muscle wasting in major muscular diseases such as cachexia or muscular dystrophy.     

Extra-nuclear signalling of estrogen receptor to breast cancer cytoskeletal remodelling, migration and invasion

Background

Estrogen is an established enhancer of breast cancer development, but less is known on its effect on local progression or metastasis. We studied the effect of estrogen receptor recruitment on actin cytoskeleton remodeling and breast cancer cell movement and invasion. Moreover, we characterized the signaling steps through which these actions are enacted.

Methodology/Principal Findings

In estrogen receptor (ER) positive T47-D breast cancer cells ER activation with 17β-estradiol induces rapid and dynamic actin cytoskeleton remodeling with the formation of specialized cell membrane structures like ruffles and pseudopodia. These effects depend on the rapid recruitment of the actin-binding protein moesin. Moesin activation by estradiol depends on the interaction of ERα with the G protein Gα₁₃, which results in the recruitment of the small GTPase RhoA and in the subsequent activation of its downstream effector Rho-associated kinase-2 (ROCK-2). ROCK-2 is responsible for moesin phosphorylation. The Gα₁₃/RhoA/ROCK/moesin cascade is necessary for the cytoskeletal remodeling and for the enhancement of breast cancer cell horizontal migration and invasion of three-dimensional matrices induced by estrogen. In addition, human samples of normal breast tissue, fibroadenomas and invasive ductal carcinomas show that the expression of wild-type moesin as well as of its active form is deranged in cancers, with increased protein amounts and a loss of association with the cell membrane.

Conclusions/Significance

These results provide an original mechanism through which estrogen can facilitate breast cancer local and distant progression, identifying the extra-nuclear Gα₁₃/RhoA/ROCK/moesin signaling cascade as a target of ERα in breast cancer cells. This information helps to understand the effects of estrogen on breast cancer metastasis and may provide new targets for therapeutic interventions.