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14 páginas.-- 7 tablas.-- 82 referencias.-- Supplementary data associated with this article can be found, in the online version, at http://dx.doi.org/10.1016/j.crvi.2017.01.004..-- M. Cantos et al. / C. R. Biologies xxx (2017) xxx–xx, [EN]: For decades, human activities have gradually destroyed the natural habitats of wild grapevine, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi, and nowadays this species is endangered in southern Europe. In this paper, 94 populations of this species have been localized and characterized in the Andalusian region in the Iberian Peninsula between 1989 and 2013. Location, ecological aspects, and sanitary characteristics are described. Must properties and in vitro tolerance to calcareous conditions were also checked. The paper also contains a global description of female and male individuals. Two hundred individuals from six river basin populations have been sampled, and their genetic structure analyzed by using 25 nuclear microsatellites loci to investigate the gene diversity of wild grape populations in Andalusia at two levels: total individuals and at river basin populations. Also, the genetic relationship of wild and cultivated accessions has been tested. Wild grapevine is considered the ancestor of the cultivated varieties and should be preserved as this material could be used to start breeding programs of cultivated varieties and also to restore riverbank forests, which constitute one of the worst preserved ecosystems in the area., [FR]: Pendant des décennies, les activités humaines ont progressivement détruit les habitats naturels de la vigne sauvage, Vitis vinifera L. subsp. sylvestris (Gmelin) Hegi et, de nos jours, cette espèce est menacée dans le Sud de l’Europe. Dans cet article, 94 populations de cette espèce ont été localisées et caractérisées en Andalousie, dans la péninsule Ibérique, entre 1989 et 2013. L’emplacement, les aspects écologiques et les caractéristiques sanitaires sont décrits. Les propriétés du moût et la tolérance in vitro aux conditions calcaires ont été également vérifiées. L’étude contient pareillement une description globale des individus féminins et masculins. Deux cents individus de six populations de bassins fluviaux ont été échantillonnés et leurs structures génétiques analysées en utilisant 25 microsatellites nucléaires pour étudier la diversité génétique des populations de raisins sauvages en Andalousie à deux niveaux : les individus totaux et les populations de bassins fluviaux. De plus, la relation génétique des accessions sauvages et cultivées a été testée. La vigne sauvage est considérée comme l’ancêtre des variétés cultivées et elle doit être préservée, car elle pourrait être utilisée pour lancer des programmes de sélection de variétés cultivées et pour restaurer les forêts riveraines, qui constituent l’un des écosystèmes les plus préservés de la région., We would like to thank the Junta de Andalucía (OG-094/04 project) and Consejo Superior de Investigaciones Científicas (201140E122 project) for financial support.

As part of an ongoing survey of scorpion diversity in Colima, Mexico, the isolated mountain Cerro Grande, part of the Biosphere Reserve Sierra de Manantlán, was investigated. Centruroides possanii sp. nov., the fifth species of the genus from the state, was discovered during fieldwork in the massif and is described in the present paper. Physiographical and climatic features of Cerro Grande may restrict the range of this new species; thus, we hypothesized that it may be a microendemic species that requires priority conservation. The new species is not assigned to any Centruroides species group recognized because some of its morphological features do not fit the current diagnosis of any of these groups, and these different groups are non-monophyletic and consequently ill-diagnosed. The new species is profusely illustrated, particularly the hemispermatophore. A distribution map is presented along with the other two more common species distributed in Colima. Because only indirect data on the potency of its venom is available, the medical importance of this new species described here is yet to be known.

Although scorpions have been described from China since the 19th century, it was only in the early 2000s that this fauna has seen a noticeable improvement in terms of the number and diversity of the described taxa. Some regions of China have been extensively prospected, while others remain largely unexplored. The latter is the case for the Province of Xinjiang, in the Extreme West of the country. A few contributions dealing with scorpions from this region are available, but these mainly concern representatives of the family Buthidae. In the present paper, a new species belonging to the genus Scorpiops Peters, of the family Scorpiopidae Kraepelin, is described from the Taxkorgan Natural Reserve. The description is based on one male and one female collected under stones at altitudes of 4500–4600 m. To our knowledge, this is the first species ever described from the Taxkorgan Natural Reserve and may represent an endemic element within the fauna of Xinjiang Province.

Morphological markers as well as two types of molecular markers, inter-sample sequence repeat (ISSR) and start codon targeted (SCoT) are suitable for species identification of the polygonati rhizoma germplasms. In this paper, we adopted these methods for the identification of rhizomes collected from 47 areas in China. Based on their morphological characters, the collected germplasms were classified into two populations, one with alternate leaf arrangement and the other with verticillate leaf arrangement, and they were comprised of five species and fourteen subgroups. Of the five species identified: Polygonatum kingianum, P. cirrhifolium, P. alternicirrhosum, and P. sibiricum belonged to one cluster, and P. cyrtonema belonged to a different cluster. According to the analysis of both ISSR and SCoT markers, all germplasms with greater genetic similarity were classified into one group. Especially, P. sibiricum and P. cirrhifolium, which shared ∼80% similarity, were clustered together, whereas the germplasms identified as P. kingianum with ∼86% similarity formed a separate clade. P. kingianum showed a much greater genetic similarity with P. cyrtonema than with P. sibiricum. The multidimensional scaling analysis further verified the accuracy and reliability of the molecular marker-based results. Thus, both morphological and molecular methods should be combined for the differentiation of germplasms such as those of polygonati rhizoma.

Metamorphosis was a key innovation in insect evolution, wherein the individual acquires characteristic adult features and stops molting during postembryonic development. The ancestral metamorphosis mode was hemimetaboly, in which the embryogenesis gives rise to a first instar nymph with the essential adult body structure. The nymphs grow gradually and the final molt to the adult stage completes the formation of functional genitalia and wings. The metamorphosis mode known as holometaboly emerged from hemimetaboly, which is characterized by embryogenesis that produces a larva with a body form that may be substantially different from that of the adult. The larva grows through various stages until molting to the pupal stage, which bridges the gap between the morphologically divergent larva and that of the winged and reproductively competent adult. In the hemimetabolan and holometabolan modes, metamorphosis is regulated by two hormones: the juvenile hormone (JH) and the ecdysone, plus its biologically active derivative, 20-hydroxyecdysone (20E). 20E is a steroid, and its main role is to promote the successive molts, including the metamorphic one, whereas JH is a terpenoid, whose function is to repress metamorphosis [1] . The action of these hormones is underpinned by the mechanisms that transduce the hormonal signal through a pathway of gene activation. The 20E signaling pathway was first described in the 1990s [2] , whereas the most important details of the JH pathway were unveiled recently. Important components of the JH signaling pathway are the JH receptor, which is the basic helix–loop–helix-Per-ARNT-Sim (bHLH-PAS) protein known as methoprene tolerant (Met), to which JH binds, as unveiled by Jindra's group in the 2010 decade. Another important component is Taiman, also a bHLH-PAS protein that plays the role of co-receptor. Finally, the transcription factor Kruppel homolog 1 (Kr-h1) is the main transducer of the antimetamorphic signal of JH [1] . Kruppel homolog 1 Kr-h1 was discovered in Drosophila melanogaster as a gene with structural similarity to the segmentation gene Kruppel, with which it shares the zinc-finger motifs and amino acid spacers connecting them. The first evidence that connected Kr-h1 and JH was also obtained in D. melanogaster. In this fly, the adult abdominal epidermis derives from larval histoblasts, which start proliferating after puparium formation. The experiments of Ashburner in 1970 showed that administration of JH prior to the prepupal stage prevents the normal differentiation of the abdominal epidermis, and the bristles that should be formed in the adult are shorter or lacking. In 2008, the experiments of Minakuchi and coworkers indicated that Kr-h1 expressed ectopically in the abdominal epidermis during metamorphosis of D. melanogaster also resulted in missing or short bristles, thereby suggesting that Kr-h1 mediates the antimetamorphic action of JH. New experiments of Minakuchi and coworkers carried out in the beetle Tribolium castaneum in 2009 showed that RNAi depletion of Kr-h1 in young larvae caused a precocious larval–pupal transformation, providing clear evidence that Kr-h1 represses metamorphosis and works downstream from Met in the JH signaling pathway. The antimetamorphic action of Kr-h1 was generalized to hemimetabolans in two parallel papers published in 2011 and conducted, respectively, in the cockroach Blattella germanica by Lozano and Belles, and the bugs Pyrrhocoris apterus and Rhodnius prolixus by Konopova and coworkers. In these two studies, RNAi experiments showed that Kr-h1 depletion in nymphs in the penultimate or antepenultimate nymphal stage triggers precocious metamorphosis [1] ( Fig. 1 A). E93 E93 is an early gene in the ecdysone signaling cascade that is specifically expressed in late prepupae of D. melanogaster. As shown by the groups of Thummel and Baehrecke in the 1990 decade, the gene encodes for a protein with RHF domains significantly similar to pipsqueak motifs, which was found to be a key player in the degeneration process of the salivary glands during D. melanogaster metamorphosis. However, the action of E93 in metamorphosis is not restricted to the regulation of degeneration processes, given that it also plays morphogenetic roles. In 2012 Mou and coworkers observed that E93 is widely expressed in adult cells of the pupa of D. melanogaster, where it is required for patterning processes. Studying the induction of the Distal-less (Dll) gene within bract cells of the pupal leg using epidermal growth factor (EGF) receptor signaling, Mou and coworkers found that E93 causes Dll to become responsive to EGF receptor signaling, thus indicating that E93 is both necessary and sufficient for determining this switch. These results suggested that E93 controls the responsiveness of many other target genes and that it is generally required for patterning during metamorphosis. Subsequent RNAi experiments reported by Urena and coworkers in 2014 showed that E93-depleted D. melanogaster larvae are able to pupate but die at the end of the pupal stage. In T. castaneum, E93 depletion by RNAi prevented the pupal–adult transition, resulting in the formation of a supernumerary second pupa. Similar results were obtained in the cockroach B. germanica, where E93 depletion in nymphs prevented the nymphal–adult transition, giving rise to repeated supernumerary nymphal instars ( Fig. 1 B). The same year, Belles and Santos showed that the expression of E93 in juvenile nymphs of B. germanica is inhibited by the transcription factor Kr-h1, thus uncovering the essential mechanism by which JH represses metamorphosis, which was named MEKRE93 pathway [3] . The MEKRE93 pathway in hemimetabolan species The observation that Kr-h1 represses E93 expression led to propose the MEKRE93 pathway as the essential axis regulating insect metamorphosis. Accordingly, in nymph–nymph transitions, JH acts through its receptor Met-Taiman to induce the expression of Kr-h1, while Kr-h1 represses the expression of E93. In contrast, the decline of JH production in the final juvenile stage interrupts Kr-h1 expression, E93 becomes de-repressed, thus triggering adult morphogenesis ( Fig. 2 A) (Belles and Santos, 2014). RNAi experiments in B. germanica by the same authors also revealed that E93 depletion increases Kr-h1 expression, thus indicating that Kr-h1 and E93 are reciprocally repressed. The inhibitory action of Kr-h1 upon E93 expression was corroborated two years later in the holometabolan T. castaneum by Urena and coworkers, which extended the MEKRE93 pathway framework to holometabolan metamorphosis. The MEKRE93 pathway in holometabolan species The main difference between the hemimetabolan and holometabolan metamorphoses is the regulation and function of the Broad complex (BR-C) zinc-finger transcription factors. In hemimetabolan species, BR-C is mainly involved in promoting the growth of wing primordia. For example, this was shown in B. germanica by Huang and coworkers in 2013, who additionally reported that BR-C expression is induced by JH and Kr-h1 during juvenile stages. One year later, Urena and coworkers found that BR-C is repressed by E93 in the metamorphic transition. Furthermore, RNAi studies made in 2019 by the group of Mito and Noji in the cricket Gryllus bimaculatus, a hemimetabolan species, confirmed the mentioned interactions, and additionally discovered that BR-C and Kr-h1 are reciprocally activated. In sharp contrast, and as shown mainly by the group of Riddiford in the decade of 1990, BR-C triggers the formation of the pupal stage in holometabolan species, where JH inhibits the expression of BR-C during larval stages and stimulates BR-C expression after pupal commitment ( Fig. 2 B). In 2019, Chafino and co-workers showed that E93 is involved in triggering the pupal stage, as it promotes BR-C expression in T. castaneum. The whole data indicates that the MEKRE93 pathway is conserved in the holometabolan species, which added the E93/BR-C interaction loop to the ancestral (hemimetabolan) pathway during the evolutionary transition from hemimetaboly to holometaboly ( Fig. 2 C).

Endocrine disruption is commonly thought to be restricted to a direct endocrine mode of action i.e. the perturbation of the activation of a given type of hormonal receptor by its natural ligand. Consistent with the WHO definition of an endocrine disrupter, a key issue is the “altered function(s) of the endocrine system”. Such altered functions can result from different chemical interactions, beyond agonistic or antagonistic effect at a given receptor. Based on neuroendocrine disruption by polychlorinated biphenyls and bisphenol A, this paper proposes different mechanistic paradigms that can result in adverse health effects. They are a consequence of altered endocrine function(s) secondary to chemical interaction with different steps in the physiological regulatory processes, thus accounting for a possibly indirect endocrine mode of action.

At the Paris Colloquium held forty years ago, and which this paper celebrates, the issue of psychosurgery had not been tackled yet. At that time psychosurgery was tainted by the controversial history of lobotomy and leucotomy. Supporters of psychosurgery at the time of the Colloquium were preparing their fourth International Conference, which was held in Madrid the following year. This represented a key characteristic of the collective, institutional and symbolic action of psychosurgery practitioners. At the end of the seventies, their strategy changed as noted below. Furthermore, we focus on the special importance of the results presented and commented on by psychosurgery supporters, including its conception and classification throughout the rhetoric historically involved (its supposed ventriloquism, its persuasive strength). Based on this view, we suggest a critical reflection encompassing old and new psychosurgery, while questioning the value of new rhetorical devices for the assessment and presentation of psychosurgery results after the surge of Deep Brain Stimulation.

In his famous book Le hasard et la necessite (1970), Monod claims that natural evolution is based on the interplay between chance and necessity bringing about adaptive evolutionary change. This article addresses a set of related questions about Monod's conception of chance: what does he mean when he uses the term “chance”? Does he invoke one or many different concepts of chance? What are the implications of his conception about the issue of the deterministic or indeterministic nature of the biological world? Is Monod's view of what chance is relevant in contemporary biology? This paper, structured by these four questions, aims at providing a synthetic study of the way Monod conceptualizes chance, particularly highlighting the metaphysical and epistemological implications of his conception and its value in biology today.

Exploiting the annotation of the western clawed frog Silurana tropicalis genome, we identified a new metallothionein (MT) gene, exhibiting all the features to be considered an active gene, but with an atypical coding region, showing only 17 cysteine residues instead of the canonical 20 cysteines of vertebrate metallothioneins and two anomalous cysteine triplets. However, the presence of a gene in the genome does not ensure its effective expression. By using conventional and Real-Time PCR analyses, we demonstrated that this atypical MT is constitutively expressed throughout the life cycle of the African clawed frog Xenopus laevis; moreover, this gene is highly expressed in the adult liver, the major site of MT expression and synthesis in vertebrates. To our knowledge, the X. laevis MT described in this paper is the first sequence of a vertebrate MT showing only 17 cysteine residues, arranged in two Cys–Cys–Cys motifs. Phylogenetic analyses also demonstrated that the atypical X. laevis MT merges in the anuran clade, but is the most derived sequence among tetrapods MTs. Finally, Tajima's Relative Rate Test suggested a different evolutionary rate between the canonical X. laevis MT and this novel isoform.

The aims of this paper were (i) to define how contrasting land uses affected plant biodiversity in Mediterranean agro-silvo-pastoral-systems across a gradient of disturbance regimes: cork oak forests, secondary grasslands, hay crops, grass covered vineyards, tilled vineyards; (ii) to determine whether these patterns mirrored those of below-ground microorganisms and whether the components of γ-diversity followed a similar model. The disturbance regimes affected plant assemblage composition. Species richness decreased with increasing land use intensity, the Shannon index showed the highest values in grasslands and hay crops. Plant assemblage composition patterns mirrored those of Basidiomycota and Ascomycota. Richness in Basidiomycota, denitrifying bacteria and microbial biomass showed the same trend as that observed for vascular plant richness. The Shannon index pattern of below-ground microorganisms was different from that of plants. The plant γ-diversity component model weakly mirrored those of Ascomycota. Patchy diversity patterns suggest that the maintenance of contrasting land uses associated with different productions typical of agro-silvo-pastoral-systems can guarantee the conservation of biodiversity.