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Abstract Improvements in the biological control of agricultural pests require improvements in the phenotyping methods used by practitioners to select efficient biological control agent (BCA) populations in industrial rearing or field conditions. Consistent inter‐individual variations in behaviour (i.e. animal personality) probably affect BCA efficiency, but have never been taken into account in the development of phenotyping methods, despite having characteristics useful for phenotyping: repeatable (by definition), often heritable, etc. We developed a video‐tracking method targeting animal personality traits and evaluated the feasibility of its use for genetic improvement in the BCA Trichogramma evanescens, by phenotyping 1,049 individuals from 24 isogenic lines. We found consistent individual variations in boldness, activity and exploration. Personality differences between the 24 isogenic lines suggested a genetic origin of the variations in activity and exploration (broad‐sense heritability estimates of 0.06 to 0.11) and revealed a trade‐off between exploration and fecundity.

We tested independently the influences of increasing temperature and decreasing moisture on life history and physiological traits in the arthropod Armadillidium vulgare. Both increasing temperature and decreasing moisture led reproductive success to decrease. While the density of immune cells decreased and the β-galactosidase activity increased with increasing temperature and decreasing moisture, which suggests a negative impact of these stressors on individual performance, increased temperature and decreased moisture affected differently the other biomarkers conjuring different underlying mechanisms depending on the stress applied. Our findings demonstrate overall a negative impact of high temperature and low moisture on woodlouse welfare. Changing temperature or moisture had slightly different effects, illustrating the need to test further the respective role of each of these key components of climate change on organisms to predict more reliably the future of our ecosystems.

We used a large dataset of greater flamingo chicks banded and measured at Camargue, France, to verify the applicability of discriminant function analysis to sex this species. Males and females sexed genetically differed significantly in all of the morphological characters measured (body mass, tarsus and wing length), with males being significantly larger than females. Although the discriminant rate varied substantially from one year to another, we found that it increased with the sample size of genetically sexed individuals. Our results suggest that discriminant function analysis (DFA) does not provide an efficient tool to sex greater flamingo chicks as these relationship are highly variable across years, requiring the genetic determination of sex on a large number of individuals every year for calibrating the DFA and still providing an overall low accuracy in sex determination. Indeed, conditions at breeding seasons can vary between years and can be considered proximate causes affecting the correct discriminant rate. Like previous studies, we recommend caution in dealing with discriminant equations computed from small datasets, and our simulation suggests that 325 genetically sexed individuals are needed to obtain 80 % correctly classified greater flamingo chicks.

Abstract Objective Glioblastoma (GBM) is the most aggressive and common form of primary brain cancer. Survival is poor and improved treatment options are urgently needed. Dual specificity phosphatase-6 (DUSP6) is actively involved in oncogenesis showing unexpected tumor-promoting properties in human glioblastoma, contributing to the development and expression of the full malignant and invasive phenotype. The purpose of this study was to assess if DUSP6 activates epithelial-to-mesenchymal transition (EMT) in glioblastoma and its connection with the invasive capacity. Results We found high levels of transcripts mRNA by qPCR analysis in a panel of primary GBM compared to adult or fetal normal tissues. At translational levels, these data correlate with high protein expression and long half-life values by cycloheximide-chase assay in immunoblot experiments. Next, we demonstrate that DUSP6 gene is involved in epithelial-to-mesenchymal transition (EMT) in GBM by immunoblot characterization of the mesenchymal and epithelial markers. Vimentin, N-Cadherin, E-Cadherin and fibronectin were measured with and without DUSP6 over-expression, and in response to several stimuli such as chemotherapy treatment. In particular, the high levels of vimentin were blunted at increasing doses of cisplatin in condition of DUSP6 over-expression while N-Cadherin contextually increased. Finally, DUSP6 per se increased invasion capacity of GBM. Overall, our data unveil the DUSP6 involvement in invasive mesenchymal-like properties in GBM.

Le bâchage peut permettre de contrôler l’expansion des espèces invasives, en particulier des renouées asiatiques. Sur la base de retours d’expériences et des quelques références présentes dans la littérature, cet article décrit les conditions d’utilisation de géotextiles ou géomembranes et apporte des préconisations techniques pour mettre en œuvre les opérations de bâchage.

Le long des voies ferrées, les gestionnaires se tournent de plus en plus vers l’éco-pâturage pour entretenir la végétation et lutter contre les espèces exotiques envahissantes. La tendance est aujourd’hui au pâturage extensif avec moins d’animaux, mais sur du plus long terme pour limiter efficacement la repousse des tiges en épuisant les réserves stockées dans les rhizomes de la plante.

Managing invasive exotic plant species is a complex challenge, especially for Asian knotweeds (Reynoutria spp.). Tarping is a regularly cited but poorly documented control method, which consists of covering the ground with a tarp (agricultural tarp, geotextile, geomembrane, etc.) to create a physical barrier to hinder plant growth and deprive the plants of light in order to deplete their rhizomatous reserves. To improve our knowledge of tarping in order to identify the key factors of its success or failure, we reviewed the relevant grey and scientific literature and conducted an international survey among managers to collect feedback on tarping experiments. In the literature, as well as in the field, practices are quite heterogeneous, and the method’s effectiveness is highly contrasted. A better consideration of knotweed biology may improve the efficacy of the method. Based on the bibliography and survey work, we propose practical recommendations including covering the entire stand, extending the tarping up to 2.5 m beyond its edges for a period of at least six years, and ensuring regular monitoring. Even though tarping does not seem to be a one-size-fits-all solution to eradicate knotweed, it could still be a useful control method once knotweed has become a critical management issue.

Le long des voies ferrées, les gestionnaires se tournent de plus en plus vers l'éco-pâturage pour entretenir la végétation et lutter contre les espèces exotiques envahissantes. La tendance est aujourd'hui au pâturage extensif avec moins d'animaux, mais sur du plus long terme pour limiter efficacement la repousse des tiges en épuisant les réserves stockées dans les rhizomes de la plante.

Le bâchage peut permettre de contrôler l'expansion des espèces invasives, en particulier des Renouées asiatiques, en témoignent de nombreux retours d'expériences et la mise sur le marché de nouvelles bâches dédiées à cet objectif. Mais l'efficacité de cette technique tient beaucoup à des modalités d'utilisation particulières qui doivent tenir compte des capacités de développement notamment souterrain des renouées. L'article donne les principales préconisations à suivre, aussi bien sur le choix du matériau et la préparation du sol, que les modalités d'installation et le suivi. Il donne également des éléments sur le cadre et le contexte d'utilisation de cette technique, au regard de son cout et de son efficacité.

Les renouées affectionnent les espaces remaniés par l'Homme et notamment les voies de transport (routes, voies ferrées, voies navigables). Leur colonisation présente alors un risque vis-à-vis de la sécurité de ces infrastructures et nécessite une gestion plus importante et plus complexe. Après avoir fait le point des différents impacts liés à la colonisation des renouées le long des voies de transport, cet article illustre comment les modes de gestion et d'entretien des emprises colonisées peuvent limiter ou favoriser la dynamique spatiale des renouées.

The PR/SET domain family (PRDM) comprise a family of genes whose protein products share a conserved N-terminal PR [PRDI-BF1 (positive regulatory domain I-binding factor 1) and RIZ1 (retinoblastoma protein-interacting zinc finger gene 1)] homologous domain structurally and functionally similar to the catalytic SET [Su(var)3-9, enhancer-of-zeste and trithorax] domain of histone methyltransferases (HMTs). These genes are involved in epigenetic regulation of gene expression through their intrinsic HMTase activity or via interactions with other chromatin modifying enzymes. In this way they control a broad spectrum of biological processes, including proliferation and differentiation control, cell cycle progression, and maintenance of immune cell homeostasis. In cancer, tumor-specific dysfunctions of PRDM genes alter their expression by genetic and/or epigenetic modifications. A common characteristic of most PRDM genes is to encode for two main molecular variants with or without the PR domain. They are generated by either alternative splicing or alternative use of different promoters and play opposite roles, particularly in cancer where their imbalance can be often observed. In this scenario, PRDM proteins are involved in cancer onset, invasion, and metastasis and their altered expression is related to poor prognosis and clinical outcome. These functions strongly suggest their potential use in cancer management as diagnostic or prognostic tools and as new targets of therapeutic intervention.

Animals foraging in the wild have to balance speed of decision making and accuracy of assessment of a food item's quality. If resource quality is important for maximizing fitness, then the duration of decision making may be in conflict with other crucial and time consuming tasks, such as anti-predator behaviours or competition monitoring. Individuals facing the risk of predation and/or competition should adjust the duration of decision making and, as a consequence, their level of choosiness for resources. When exposed to predation, the forager could either maintain its level of choosiness for food items but accept a reduction in the amount of food items consumed or it could reduce its level of choosiness and accept all prey items encountered. Under competition risk, individuals are expected to reduce their level of choosiness as slow decision making exposes individuals to a higher risk of opportunity costs. To test these predictions, the level of choosiness of a seed-eating carabid beetle, Harpalus affinis, was examined under 4 different experimental conditions of risk: i) predation risk; ii) intraspecific competition; iii) interspecific competition; and, iv) control. All the risks were simulated using chemical cues from individual conspecifics or beetles of different species that are predatory or granivorous. Our results show that when foraging under the risk of predation, H. affinis individuals significantly reduce their level of choosiness for seeds. Reductions in level of choosiness for food items might serve as a sensible strategy to reduce both the total duration of a foraging task and the cognitive load of the food quality assessment. No significant differences were observed when individuals were exposed to competition cues. Competition, (i.e opportunity cost) may not be perceived as risk high enough to induce changes in the level of choosiness. Our results suggest that considering the amount of items consumed, alone, would be a misleading metric when assessing individual response to a risk of predation. Foraging studies should therefore also take in account the decision making process.

Adipose tissue is a key regulator of energy balance playing an active role in lipid storage as well as in synthesizing several hormones directly involved in the pathogenesis of obesity. Obesity represents a peculiar risk factor for a growing list of cancers and is frequently associated to poor clinical outcome. The mechanism linking obesity and cancer is not completely understood, but, amongst the major players, there are both chronic low-grade inflammation and deregulation of adipokines secretion. In obesity, the adipose tissue is pervaded by an abnormal number of immune cells that create an inflammatory environment supporting tumor cell proliferation and invasion. Adiponectin (APN), the most abundant adipokine, shows anti-inflammatory, anti-proliferative and pro-apoptotic properties. Circulating levels of APN are drastically decreased in obesity, suggesting that APN may represent the link factor between obesity and cancer risk. The present review describes the recent advances on the involvement of APN and its receptors in the etiology of different types of cancer.

PRDM (PRDI-BF1 and RIZ homology domain containing) protein family members are characterized by the presence of a PR domain and a variable number of Zn-finger repeats. Experimental evidence has shown that the PRDM proteins play an important role in gene expression regulation, modifying the chromatin structure either directly, through the intrinsic methyltransferase activity, or indirectly through the recruitment of chromatin remodeling complexes. PRDM proteins have a dual action: they mediate the effect induced by different cell signals like steroid hormones and control the expression of growth factors. PRDM proteins therefore have a pivotal role in the transduction of signals that control cell proliferation and differentiation and consequently neoplastic transformation. In this review, we describe pathways in which PRDM proteins are involved and the molecular mechanism of their transcriptional regulation.

Estrogens promote a plethora of effects in the CNS that profoundly affect both its development and mature functions and are able to influence proliferation, differentiation, survival and neurotransmission. The biological effects of estrogens are cell-context specific and also depend on differentiation and/or proliferation status in a given cell type. Furthermore, estrogens activate ERK1/2 in a variety of cellular types. Here, we investigated whether ERK1/2 activation might be influenced by estrogens stimulation according to the differentiation status and the molecular mechanisms underling this phenomenon. ERK1/2 exert an opposing role on survival and death, as well as on proliferation and differentiation depending on different kinetics of phosphorylation. Hence we report that mesencephalic primary cultures and the immortalized cell line mes-c-myc A1 express estrogen receptor α and activate ERK1/2 upon E2 stimulation. Interestingly, following the arrest of proliferation and the onset of differentiation, we observe a change in the kinetic of ERKs phosphorylation induced by estrogens stimulation. Moreover, caveolin-1, a main constituent of caveolae, endogenously expressed and co-localized with ER-α on plasma membrane, is consistently up-regulated following differentiation and cell growth arrest. In addition, we demonstrate that siRNA-induced caveolin-1 down-regulation or disruption by means of ß-cyclodextrin treatment changes ERK1/2 phosphorylation in response to estrogens stimulation. Finally, caveolin-1 down-regulation abolishes estrogens-dependent survival of neurons. Thus, caveolin-1 appears to be an important player in mediating, at least, some of the non-genomic action of estrogens in neurons, in particular ERK1/2 kinetics of activation and survival.

Testicular germ cell tumors (TGCTs) derive from primordial germ cells. Their maturation is blocked at different stages, reflecting histological tumor subtypes. A common genetic alteration in TGCT is a deletion of the chromosome 1 short arm, where the PRDM2 gene, belonging to the Positive Regulatory domain gene (PRDM) family, is located. Expression of PRDM2 gene is shifted in different human tumors, where the expression of the two principal protein forms coded by PRDM2 gene, RIZ1 and RIZ2, is frequently unbalanced. Therefore, PRDM2 is actually considered a candidate tumor suppressor gene in different types of cancer. Although recent studies have demonstrated that PRDM gene family members have a pivotal role during the early stages of testicular development, no information are actually available on the involvement of these genes in TGCTs. In this article we show by qRT-PCR analysis that PRDM2 expression level is modulated by proliferation and differentiation agents such as estradiol, whose exposure during fetal life is probably an important risk factor for TGCTs development in adulthood. Furthermore in normal and cancer germ cell lines, PRDM2 binds estradiol receptor α (ERα) and influences proliferation, survival and apoptosis, as previously reported using MCF-7 breast cancer cell line, suggesting a potential tumor-suppressor role in TGCT formation.

In order to minimize risks of pathogen transmission with the development of ecotourism in Gabon, a seasonal inventory has been performed in five contrasted biotopes in Ivindo (INP) and Moukalaba-Doudou (MDNP) National Parks. A total of 10,033 hematophagous flies were captured. The Glossinidae, with six different species identified, was the most abundant group and constitutes about 60% of the captured flies compared to the Stomoxys (6 species also identified) and Tabanidae with 28% and 12%, respectively. The Glossinidae showed a higher rate of capture in primary forest and in research camps. In INP, the Stomoxys showed a higher rate of capture in secondary forest and at village borders, whereas in MDNP the Stomoxys were captured more in the savannah area. Thus, each fly group seemed to reach maximum abundance in different habitats. The Glossinidae were more abundant in primary forest and near research camps while Stomoxys were more abundant in secondary forest and savannah. The Tabanidae did not show a clear habitat preference.

Evaluation of response to neoadjuvant radiotherapy (NART) does not consider soft tissue sarcoma (STS) heterogeneity. We aimed to investigate radiological and pathological response of 4 major histotypes. Extremity or trunk STS patients who received 50 Gy NART between 2009 and 2020 were retrospectively included. Relative variation in tumor size (RVTS) and pathological response were reported in the overall population and in undifferentiated pleomorphic sarcoma (UPS), myxofibrosarcoma (MFS), myxoid liposarcoma (MLS) and synovial sarcoma (SS) patients to identify response modalities of each histotype. Among the 121 included patients, 49, 19, 13 and 11 presented UPS, MFS, MLS and SS. Median RVTS were 0% (IQR -18-+18), +8% (IQR 0-+24), −12% (IQR -20–3) and −11% (IQR -15–9), respectively (p = 0.001). Median viable cells were 10%, 60%, 20% and 70% (p = 0.007). In overall population, pathological complete response and median necrosis were 27.7% and 10% without significant correlation to histotype (p = 0.18 and 0.06). Nineteen (38.8%) UPS specimens presented cysts that were emptied during the sampling process and distorted the microscopic response evaluation. Infiltrative growth pattern was observed in 28% and 38.9% UPS and MFS patients. Five (38.5%) MLS presented mature adipocytes without proven prognostic value. Cysts were observed in 36% of SS specimens. In the absence of initial tumor limits, the great viable cellularity of SS may be overestimated by their nodular aspect. After NART, we highlighted disparate response of UPS, frequent progression of MFS, and confirmed MLS and SS radiosensitivity. Response must be interpreted with caution and consider the histotype-specific patterns. [ABSTRACT FROM AUTHOR]