Molecular Diagnosis of Neonatal Diabetes Mellitus Using Next-Generation Sequencing of the Whole Exome

Background: Accurate molecular diagnosis of monogenic non-autoimmune neonatal diabetes mellitus (NDM) is critical for patient care, as patients carrying a mutation in KCNJ11 or ABCC8 can be treated by oral sulfonylurea drugs instead of insulin therapy. This diagnosis is currently based on Sanger sequencing of at least 42 PCR fragments from the KCNJ11, ABCC8, and INS genes. Here, we assessed the feasibility of using the next-generation whole exome sequencing (WES) for the NDM molecular diagnosis. Methodology/Principal Findings: We carried out WES for a patient presenting with permanent NDM, for whom mutations in KCNJ11, ABCC8 and INS and abnormalities in chromosome 6q24 had been previously excluded. A solution hybridization selection was performed to generate WES in 76 bp paired-end reads, by using two channels of the sequencing instrument. WES quality was assessed using a high-resolution oligonucleotide whole-genome genotyping array. From our WES with high-quality reads, we identified a novel non-synonymous mutation in ABCC8 (c.1455G.C/p.Q485H), despite a previous negative sequencing of this gene. This mutation, confirmed by Sanger sequencing, was not present in 348 controls and in the patient’s mother, father and young brother, all of whom are normoglycemic. Conclusions/Significance: WES identified a novel de novo ABCC8 mutation in a NDM patient. Compared to the current Sanger protocol, WES is a comprehensive, cost-efficient and rapid method to identify mutations in NDM patients. W

Rapid Host Defense against Aspergillus fumigatus Involves Alveolar Macrophages with a Predominance of Alternatively Activated Phenotype

The ubiquitous fungus Aspergillus fumigatus is associated with chronic diseases such as invasive pulmonary aspergillosis in immunosuppressed patients and allergic bronchopulmonary aspergillosis (ABPA) in patients with cystic fibrosis or severe asthma. Because of constant exposure to this fungus, it is critical for the host to exercise an immediate and decisive immune response to clear fungal spores to ward off disease. In this study, we observed that rapidly after infection by A. fumigatus, alveolar macrophages predominantly express Arginase 1 (Arg1), a key marker of alternatively activated macrophages (AAMs). The macrophages were also found to express Ym1 and CD206 that are also expressed by AAMs but not NOS2, which is expressed by classically activated macrophages. The expression of Arg1 was reduced in the absence of the known signaling axis, IL-4Rα/STAT6, for AAM development. While both Dectin-1 and TLR expressed on the cell surface have been shown to sense A. fumigatus, fungus-induced Arg1 expression in CD11c+ alveolar macrophages was not dependent on either Dectin-1 or the adaptor MyD88 that mediates intracellular signaling by most TLRs. Alveolar macrophages from WT mice efficiently phagocytosed fungal conidia, but those from mice deficient in Dectin-1 showed impaired fungal uptake. Depletion of macrophages with clodronate-filled liposomes increased fungal burden in infected mice. Collectively, our studies suggest that alveolar macrophages, which predominantly acquire an AAM phenotype following A. fumigatus infection, have a protective role in defense against this fungus

Biotic and environmental dynamics through the Late Jurassic-Early Cretaceous transition: evidence for protracted faunal and ecological turnover

The Late Jurassic to Early Cretaceous interval represents a time of environmental upheaval and cataclysmic events, combined with disruptions to terrestrial and marine ecosystems. Historically, the Jurassic/Cretaceous (J/K) boundary was classified as one of eight mass extinctions. However, more recent research has largely overturned this view, revealing a much more complex pattern of biotic and abiotic dynamics than has previously been appreciated. Here, we present a synthesis of our current knowledge of Late Jurassic–Early Cretaceous events, focusing particularly on events closest to the J/K boundary. We find evidence for a combination of short-term catastrophic events, large-scale tectonic processes and environmental perturbations, and major clade interactions that led to a seemingly dramatic faunal and ecological turnover in both the marine and terrestrial realms. This is coupled with a great reduction in global biodiversity which might in part be explained by poor sampling. Very few groups appear to have been entirely resilient to this J/K boundary ‘event’, which hints at a ‘cascade model’ of ecosystem changes driving faunal dynamics. Within terrestrial ecosystems, larger, more-specialised organisms, such as saurischian dinosaurs, appear to have suffered the most. Medium-sized tetanuran theropods declined, and were replaced by larger-bodied groups, and basal eusauropods were replaced by neosauropod faunas. The ascent of paravian theropods is emphasised by escalated competition with contemporary pterosaur groups, culminating in the explosive radiation of birds, although the timing of this is obfuscated by biases in sampling. Smaller, more ecologically diverse terrestrial non-archosaurs, such as lissamphibians and mammaliaforms, were comparatively resilient to extinctions, instead documenting the origination of many extant groups around the J/K boundary. In the marine realm, extinctions were focused on low-latitude, shallow marine shelf-dwelling faunas, corresponding to a significant eustatic sea-level fall in the latest Jurassic. More mobile and ecologically plastic marine groups, such as ichthyosaurs, survived the boundary relatively unscathed. High rates of extinction and turnover in other macropredaceous marine groups, including plesiosaurs, are accompanied by the origin of most major lineages of extant sharks. Groups which occupied both marine and terrestrial ecosystems, including crocodylomorphs, document a selective extinction in shallow marine forms, whereas turtles appear to have diversified. These patterns suggest that different extinction selectivity and ecological processes were operating between marine and terrestrial ecosystems, which were ultimately important in determining the fates of many key groups, as well as the origins of many major extant lineages. We identify a series of potential abiotic candidates for driving these patterns, including multiple bolide impacts, several episodes of flood basalt eruptions, dramatic climate change, and major disruptions to oceanic systems. The J/K transition therefore, although not a mass extinction, represents an important transitional period in the co-evolutionary history of life on Earth

Effets comparés de l'histamine sur la rate ovariectomisée en fonction du site osseux

Le but de notre travail était d'étudier le rôle de l'histamine dans les mécanismes de résorption osseuse sur le modèle de la rate ovariectomisée. Dans un premier temps, nous avons montré sur le fémur, par l'utilisation d'une molécule anti-histaminique, la famotidine, que l'histamine n'est impliquée que dans la première phase de la résorption osseuse. En effet, six mois après ovariectomie, l'effet protecteur de la famotidine n'est pas retrouvé sur le fémur. Par contre, cet effet est toujours présent sur la vertèbre à 6 mois, os au niveau duquel la résorption osseuse se fait beaucoup plus tardivement. Puis, nous avons tenté d'évaluer les effets de l'ovariectomie et de la supplémentation en œstrogènes (17b-estradiol) sur un autre type d'os, l'os basai mandibulaire. Nos résultats révèlent que contrairement à l'os fémoral, l'os basai mandibulaire semble être insensible à la déplétion œstrogénique et au traitement à Festradiol. Les effets de l'ovariectomie au niveau mandibulaire étant différents de ceux constatés sur un os long, nous nous sommes demandé si une autre enveloppe mandibulaire réagissait de façon similaire. Nous avons donc choisi d'étudier dans notre troisième partie la réaction de l'os alvéolaire à travers un modèle de migration physiologique. Nous avons ainsi montré que la migration dentaire physiologique est temporairement augmentée après ovariectomie. Les effets de l'ovariectomie ne sont pas seulement région dépendantes, elles sont également -enveloppe-dépendantes. De plus, la composante radiculaire de l'appareil d'ancrage semble-être susceptible à l'ovariectomie car nous avons constaté une augmentation de la résorption radiculaire. Cependant, il semble que ce phénomène ne se produise que dans des zones déjà en résorptionThe aim of this study was to experiment on the role of histamine in the bone resorption of ovariectomized rats. Experimenting on the femur with famotidine, an anti-histaminic molecule, we first showed that histamine is involved only in the first phase of bone resorption. Indeed, six months after ovariectomy, the protective effect of famotidine was not found even though this effect is still present in the vertebrae at six months. In the vertebrae, the bone resorption appears later. Then, we attempted to study the effect of ovariectomy and of estrogen (17b-estradiol) supplementation on another type of bone, the basal mandibular bone. Contrary to femoral bone, basal mandibular bone seems to be less sensitive to estrogen depletion and 17b-estradiol supplementation. Since ovariectomy has a different effect on the mandible than on long bones, we wondered if other bone envelops would react in the same way. In the third part of this work, we studied the reaction of the alveolar bone in a model of physiologic migration. We evidenced that physiologic dental migration increases temporarily after ovariectomy. The effects of ovariectomy are not only region-dependant but also envelop-dependant. Ovariectomy seems to have an effect on the attachment system because we observed an increase of bone resorption. However it seems that this phenomenon only occurs in zones that already undergoing active resorption.MONTROUGE-BUFR Odontol.PARIS5 (920492101) / SudocSudocFranceF

Genomewide Search for Type 2 Diabetes–Susceptibility Genes in French Whites: Evidence for a Novel Susceptibility Locus for Early-Onset Diabetes on Chromosome 3q27-qter and Independent Replication of a Type 2–Diabetes Locus on Chromosome 1q21–q24

Despite recent advances in the molecular genetics of type 2 diabetes, the majority of susceptibility genes in humans remain to be identified. We therefore conducted a 10-cM genomewide search (401 microsatellite markers) for type 2 diabetes–related traits in 637 members of 143 French pedigrees ascertained through multiple diabetic siblings, to map such genes in the white population. Nonparametric two-point and multipoint linkage analyzes—using the MAPMAKER-SIBS (MLS) and MAXIMUM-BINOMIAL-LIKELIHOOD (MLB) programs for autosomal markers and the ASPEX program for chromosome X markers—were performed with six diabetic phenotypes: diabetes and diabetes or glucose intolerance (GI), as well as with each of the two phenotypes associated with normal body weight (body-mass index<27 kg/m(2)) or early age at diagnosis (<45 years). In a second step, high-resolution genetic mapping (∼2 cM) was performed in regions on chromosomes 1 and 3 loci showing the strongest linkage to diabetic traits. We found evidence for linkage with diabetes or GI diagnosed at age <45 years in 92 affected sib pairs from 55 families at the D3S1580 locus on chromosome 3q27-qter using MAPMAKER-SIBS (MLS = 4.67, P=.000004), supported by the MLB statistic (MLB-LOD=3.43, P=.00003). We also found suggestive linkage between the lean diabetic status and markers APOA2–D1S484 (MLS = 3.04, P=.00018; MLB-LOD=2.99, P=.00010) on chromosome 1q21-q24. Several other chromosomal regions showed indication of linkage with diabetic traits, including markers on chromosome 2p21-p16, 10q26, 20p, and 20q. These results (a) showed evidence for a novel susceptibility locus for type 2 diabetes in French whites on chromosome 3q27-qter and (b) confirmed the previously reported diabetes-susceptibility locus on chromosome 1q21-q24. Saturation on both chromosomes narrowed the regions of interest down to an interval of <7 cM

Genetic mapping of sex and self-incompatibility determinants in the androdioecious plant Phillyrea angustifolia

A bstract The diversity of mating and sexual systems in angiosperms is spectacular, but the factors driving their evolution remain poorly understood. In plants of the Oleaceae family, an unusual self-incompatibility (SI) system has been discovered recently, whereby only two distinct homomorphic SI specificities segregate stably. To understand the role of this peculiar SI system in preventing or promoting the diversity of sexual phenotypes observed across the family, an essential first step is to characterize the genetic architecture of these two traits. Here, we developed a high-density genetic map of the androdioecious shrub P. angustifolia based on a F1 cross between a hermaphrodite and a male parent with distinct SI genotypes. Using a double restriction-site associated digestion (ddRAD) sequencing approach, we obtained reliable genotypes for 196 offspring and their two parents at 10,388 markers. The resulting map comprises 23 linkage groups totaling 1,855.13 cM on the sex-averaged map. We found strong signals of association for the sex and SI phenotypes, that were each associated with a unique set of markers on linkage group 12 and 18 respectively, demonstrating inheritance of these traits as single, independent, mendelian factors. The P. angustifolia linkage map shows robust synteny to the olive tree genome overall. Two of the six markers strictly associated with SI in P. angustifolia have strong similarity with a recently identified 741kb chromosomal region fully linked to the SI phenotype on chromosome 18 of the olive tree genome, providing strong cross-validation support. The SI locus stands out as being markedly rearranged, while the sex locus has remained relatively more collinear between the two species. This P. angustifolia linkage map will be a useful resource to investigate the various ways by which the sex and SI determination systems have co-evolved in the broader phylogenetic context of the Oleaceae family

Cartographie génétique des déterminants du sexe et de l'auto-incompatibilité chez la plante androdioïque Phillyrea angustifolia

International audienceThe diversity of mating and sexual systems in angiosperms is spectacular, but the factors driving their evolution remain poorly understood. In plants of the Oleaceae family, an unusual self-incompatibility (SI) system has been discovered recently, whereby only two distinct homomorphic SI specificities segregate stably. To understand the role of this peculiar SI system in preventing or promoting the diversity of sexual phenotypes observed across the family, an essential first step is to characterize the genetic architecture of these two traits. Here, we developed a high-density genetic map of the androdioecious shrub P. angustifolia based on a F1 cross between a hermaphrodite and a male parent with distinct SI genotypes. Using a double restriction-site associated digestion (ddRAD) sequencing approach, we obtained reliable genotypes for 196 offspring and their two parents at 10,388 markers. The resulting map comprises 23 linkage groups totaling 1,855.13 cM on the sexaveraged map. We found strong signals of association for the sex and SI phenotypes, that were each associated with a unique set of markers on linkage group 12 and 18 respectively, demonstrating inheritance of these traits as single, independent, mendelian factors. The P. angustifolia linkage map shows robust synteny to the olive tree genome overall. Two of the six markers strictly associated with SI in P. angustifolia have strong similarity with a recently identified 741kb chromosomal region fully linked to the SI phenotype on chromosome 18 of the olive tree genome, providing strong cross-validation support. The SI locus stands out as being markedly rearranged, while the sex locus has remained relatively more collinear between the two species. This P. angustifolia linkage map will be a useful resource to investigate the various ways by which the sex and SI determination systems have co-evolved in the broader phylogenetic context of the Oleaceae family.La diversité des systèmes de reproduction et des types sexuels chez les angiospermes est spectaculaire, mais les facteurs de leur évolution restent mal compris. Chez les plantes de la famille des Oleacées, un système d'auto-incompatibilité (SI) inhabituel a été découvert récemment, dans lequel seules deux spécificités SI distinctes mais parfaitement homomorphes ségrégent de manière stable. Pour comprendre le rôle de ce système SI particulier dans la prévention ou la promotion de la diversité des phénotypes sexuels observés dans la famille des Oléacées, une première étape essentielle est de caractériser l'architecture génétique de ces deux traits. Ici, nous avons développé une carte génétique à haute densité de l'arbuste androdioïque P. angustifolia basée sur un croisement F1 entre un hermaphrodite et un parent mâle avec des génotypes SI distincts. En utilisant une approche de séquençage par double digestion associée à un site de restriction (ddRAD), nous avons obtenu des génotypes fiables pour 196 descendants et leurs deux parents sur 10 388 marqueurs. La carte résultante comprend 23 groupes de liaison totalisant 1 855,13 cM sur la carte moyenne par sexe. Nous avons trouvé de forts signaux d'association pour les phénotypes sexe et SI, qui étaient chacun associés à un ensemble unique de marqueurs sur les groupes de liaison 12 et 18 respectivement, démontrant l'héritage de ces traits comme facteurs mendéliens uniques et indépendants. La carte de liaison de P. angustifolia montre une synténie robuste avec le génome de l'olivier dans son ensemble. Deux des six marqueurs strictement associés au SI chez P. angustifolia présentent une forte similitude avec une région chromosomique de 741 kb récemment identifiée et entièrement liée au phénotype SI sur le chromosome 18 du génome de l'olivier, ce qui fournit une forte validation croisée. Le locus SI se distingue par un réarrangement marqué, tandis que le locus sexuel est resté relativement colinéaire entre les deux espèces. Cette carte de liaison de P. angustifolia sera une ressource utile pour étudier les différentes façons dont les systèmes de détermination du sexe et du SI ont co-évolué dans le contexte phylogénétique plus large de la famille des Oléacées