Sources of (co)variation in alternative siring routes available to male great tits (Parus major)

Males of socially monogamous species can increase their siring success via within‐pair and extra‐pair fertilizations. In this study, we focused on the different sources of (co)variation between these siring routes, and asked how each contributes to total siring success. We quantified the fertilization routes to siring success, as well as behaviors that have been hypothesized to affect siring success, over a five‐year period for a wild population of great tits Parus major. We considered siring success and its fertilization routes as “interactive phenotypes” arising from phenotypic contributions of both members of the social pair. We show that siring success is strongly affected by the fecundity of the social (female) partner. We also demonstrate that a strong positive correlation between extra‐pair fertilization success and paternity loss likely constrains the evolution of these two routes. Moreover, we show that more explorative and aggressive males had less extra‐pair fertilizations, whereas more explorative females laid larger clutches. This study thus demonstrates that (co)variation in siring routes is caused by multiple factors not necessarily related to characteristics of males. We thereby highlight the importance of acknowledging the multilevel structure of male fertilization routes when studying the evolution of male mating strategies.     

High sensitivity enzyme-linked immunosorbent assay (ELISA) method for measuring protein carbonyl in samples with low amounts of protein

The oxidative modification of proteins has been shown to play a major role in a number of pathological processes. One such modification is the addition of the carbonyl groups to the amino acid residue in proteins. For the measurement of the carbonyl groups in low concentration protein samples, we have modified the ELISA (enzyme-linked immunosorbent assay) method that was developed by Buss et al. [Buss, I. H; Chan, T. P.; Sluis, K. B.; Domigan, N. M.; Winterbourn, C. C. Protein carbonyl measurement by a sensitive ELISA method. Free Radic. Biol. Med.23:361-366; 1997 ]. In the modified method, protein samples diluted in phosphate-buffered saline were adsorbed to wells of an ELISA plate and then reacted with dinitrophenylhydrazine (DNPH). The protein-conjugated DNPH was probed by a commercial anti-DNPH antibody, and then a second antibody conjugated with horseradish peroxidase was added for quantification. The method was calibrated using oxidized albumin, and required only 5 mug protein. This obviated the need to concentrate protein in experimental and clinical samples with low amounts of protein. In addition the effect of TCA on carbonyl measurement is eliminated. The standard curve was linear in the range of 0-3.36 nmol carbonyls/mg protein, which is the range within which clinical samples fell. The results correlated well with the colorimetric carbonyl assay. The method was used to analyze the amount of protein carbonyl in aqueous humor and diluted plasma samples.     

Influence of wind loading on root system development and architecture in oak (Quercus robur L.) seedlings.

The effect of wind loading on seedlings of English oak (Quercus robur L.) was investigated. Instead of using a traditional wind tunnel, an innovative ventilation system was designed. This device was set up in the field and composed of a rotating arm supporting an electrical fan, which emitted an air current similar to that of wind loading. Oaks were sown from seed in a circle around the device. A block of control plants was situated nearby, and was not subjected to artificial wind loading. After 7 months, 16 plants from each treatment were excavated, and root architecture and morphological characteristics measured using a 3D digitiser. The resulting geometrical and topological data were then analysed using AMAPmod software. Results showed that total lateral root number and length in wind stressed plants were over two times greater than that in control trees. However, total lateral root volume did not differ significantly between treatments. In comparing lateral root characters between the two populations, it was found that mean root length, diameter and volume were similar between the two treatments. In trees subjected to wind loading, an accentuated asymmetry of root distribution and mean root length was found between the windward and leeward sides of the root system, with windward roots being significantly more numerous and longer than leeward roots. However, no differences were found when the two sectors perpendicular to the wind direction were compared. Mean tap root length was significantly higher in control samples compared to wind stressed plants, whilst mean diameter was greater in the latter. Wind loading appears to result in increased growth of lateral roots at the expense of the tap root. Development of the lateral root system may therefore ensure better anchorage of young trees subjected to wind loading under certain conditions.     

Partnership between academic research and industry to study a new anti-osteoporotic drug

The activity of the osteoclast, the cell responsible for bone resorption, is subjected to different regulation factors. Amongst these, those issued from the matrix, particularly released minerals such as calcium, are determinants. We have shown that variations in calcium concentration in the medium regulates resorption activity and duration of the osteoclast lifespan. The development of a new therapeutic agent, strontium ranelate, has shown very interesting clinical effects reliant on the stimulation of bone formation activity by osteoblasts and modulation of bone resorption activity. From our knowledge regarding osteoclast physiology, in particular calcium signaling pathways, and the control of different osteoclast cellular models, a consequent collaboration was formed between our laboratory and Servier in order to elaborate on the effects of strontium ranelate on the osteoclast. In several years, this collaboration has been further enriched by other collaborators in order to better understand this mechanism. It has also been shown that strontium likely interacts with the calcium-sensing receptor and that the pathways of intracellular signaling pathways activated by calcium and strontium ranelate via this receptor are different. In fact, within the scope of this collaboration with Servier, exchanges with other academic laboratories were initiated and collaboration on numerous techniques became possible. Then, it has been possible to confirm the presence of the calcium-sensing receptor on the osteoclasts and to demonstrate its role in the molecular events associated with strontium ranelate's effects on the osteoclast.     

Unexpected phenology and lifespan of shallow and deep fine roots of walnut trees grown in a silvoarable Mediterranean agroforestry system

Plant and Soil - Fine roots play a major role in the global carbon cycle through respiration, exudation and decomposition processes, but their dynamics are poorly understood. Current estimates of...     

Study of potent cytotoxic activity of Helleborus cyclophyllus Boiss against a human adenocarcinoma cell line

Helleborus cyclophyllus Boiss is a rhizomatous plant species, with strong allelochemical properties, that has been used since ancient times for its therapeutic properties. In the present study we investigated the ability of an aqueous-soluble fraction of the methanol extract of H. cyclophyllus Boiss leaves, to induce apoptotic cell death on A549 human bronchial epithelial adenocarcinoma cells. A primary human lung fibroblasts’ cell line was used as a model of normal-healthy cells for comparison. Cell morphology was examined after appropriate staining, cytotoxic activity of the extract was determined by the MTT assay, the type of cell death was analyzed by flow cytometry, confirmation of apoptosis was evaluated with the analysis of caspase-3, PARP1 by western blotting, while the chemical composition was assessed by liquid chromatography–tandem mass spectrometry (LC–MS/MS). H. cyclophyllus Boiss extract was selectively active on A549 cells inducing significant morphological changes, even at low concentrations. Characteristic morphological alterations included the release of vesicular formations from A549 cell membranes (ectosomes), detachment of cells from their substrate, generation of a large vesicle into the cytoplasm (thanatosome) and the formation of apoptotic bodies. The selective apoptotic action on treated cells was also confirmed by biochemical criteria. Low concentrations, however, did not affect normal cells. The phytochemical analysis of the extract revealed the presence of cardiac glucosides, bufadienolides and phytoecdysteroids. To the best of our knowledge, the above-mentioned sequences of events leading selectively cancer cells to apoptosis, has not been reported before.Electronic supplementary materialThe online version of this article (10.1007/s10616-020-00425-4) contains supplementary material, which is available to authorized users.