26 research outputs found

    Data from: Stay at home aphids: comparative spatial and seasonal metapopulation structure and dynamics of two specialist tansy aphid species studied using microsatellite markers

    No full text
    Two tansy-feeding aphids – Macrosiphoniella tanacetaria (MA) and Metopeurum fuscoviride (ME) – were studied at a small spatial scale in and around Jena (< 80 km2) using polymorphic microsatellite markers. Both species were found in ~ 60% of sites formerly known to harbour the aphids, although generally when they did occur, they occurred singly (MA ~ 50%; ME ~60%) and rarely together on the same plant at the same time (~10%) and then usually only in the early part of the growing season. This difference may be due to quasi-apparent competition effects elicited to ants farming ME aphids, and preferentially actively eliminating or disturbing MA aphids. In terms of population genetics, both aphids showed extreme genetic heterogeneity within a metapopulation structure, ME more than MA, i.e. higher FST values, ~ 0.4 vs. 0.15, respectively, and limited levels of interpopulation gene flow. Subpopulations often deviated from Hardy-Weinberg equilibrium and showed linkage disequilibria, as expected in animals with extended parthenogenetic reproduction, and had positive FIS values for most large samples, suggesting inbreeding, and possibly philopatry, certainly in ME. Hierarchical analysis (allele range and number per locus, analysis of molecular variance and FST) strongly suggested that the plant rather than site governs the level of genetic variation. Bayesian clustering analysis revealed that both species had heterogeneous historical genetic patterning, with K (number of subgroups) ranging from 3-7. Evidence is also provided from isolation by distance (IBD) and private allele analyses, that in MA, the presence of winged autumn males, absent in ME where males are wingless, influences comparative population genetic structuring, such that ME subpopulations are comparatively more inbred and genetically differentiated than MA subpopulations. Lastly, additional spatial arrangement (ALLELES-IN-SPACE) analysis showed that in both species, certain subpopulations were genetically isolated from the remainder, probably due to geographical barriers, including intervening buildings and woods. As such, the biology of these tansy aphids living in semi-natural habitats is very different from many pest aphid species examined within agro-ecosystems and infesting ephemeral crops, since the former seem much more reluctant to fly and hence show contrastingly much higher levels of interpopulation divergence, even at small spatial scales as here investigated. Indeed, the number of genotypic clusters found for tansy aphids found using Bayesian approaches is similar to that for the major pest the peach-potato aphid, Myzus persicae, globally

    Long term behavioural outcome after neonatal arterial switch operation for transposition of the great arteries

    No full text
    Aims: To evaluate behavioural outcome and quality of life in children aged 8–14 years after neonatal arterial switch operation for transposition of the great arteries. Methods: Sixty children operated as neonates with combined deep hypothermic circulatory arrest and low flow cardiopulmonary bypass were evaluated at age 7.9–14.3 years by the Child Behaviour Checklist (CBCL) and the Inventory for the Assessment of the Quality of Life in Children and Adolescents (IQCL). Results: Parent reported behavioural outcome on all CBCL problem and competence scores was worse, whereas quality of life on self reported IQCL scores was not reduced compared to the normal population. On multivariate analysis, severe preoperative hypoxia was related to parent reported social problems; peri- and postoperative cardiocirculatory insufficiency was associated with internalising, externalising, attention, and total behavioural problems. Reduced expressive language was associated with total behavioural problems, and poor academic achievement was related to parent reported deficits in school performance. Impaired neurological status and reduced endurance capacity both predicted self reported stress by illness. Conclusions: The neonatal arterial switch operation with combined circulatory arrest and low flow bypass is associated with parent reported long term behavioural impairment, but not with self reported general reduction in quality of life. This discrepancy may be a result of different perception of illness. In our experience, increased risk of long term psychosocial maladjustment after neonatal corrective cardiac surgery is related to the presence of neurological impairment and reduced endurance capacity

    Using multiple landscape genetic approaches to test the validity of genetic clusters in a species characterized by an isolation-by-distance pattern

    No full text
    Bayesian clustering methods are typically used to identify barriers to gene flow, but they are prone to deduce artificial subdivisions in a study population characterized by an isolation-by-distance pattern (IbD). Here we analysed the landscape genetic structure of a population of wild boars (Sus scrofa) from south-western Germany. Two clustering methods inferred the presence of the same genetic discontinuity. However, the population in question was characterized by a strong IbD pattern. While landscape-resistance modelling failed to identify landscape features that influenced wild boar movement, partial Mantel tests and multiple regression of distance matrices (MRDMs) suggested that the empirically inferred clusters were separated by a genuine barrier. When simulating random lines bisecting the study area, 60% of the unique barriers represented, according to partial Mantel tests and MRDMs, significant obstacles to gene flow. By contrast, the random-lines simulation showed that the boundaries of the inferred empirical clusters corresponded to the most important genetic discontinuity in the study area. Given the degree of habitat fragmentation separating the two empirical partitions, it is likely that the clustering programs correctly identified a barrier to gene flow. The differing results between the work published here and other studies suggest that it will be very difficult to draw general conclusions about habitat permeability in wild boar from individual studies

    An AKAP-Lbc-RhoA interaction inhibitor promotes the translocation of aquaporin-2 to the plasma membrane of renal collecting duct principal cells

    Get PDF
    Stimulation of renal collecting duct principal cells with antidiuretic hormone (arginine-vasopressin, AVP) results in inhibition of the small GTPase RhoA and the enrichment of the water channel aquaporin-2 (AQP2) in the plasma membrane. The membrane insertion facilitates water reabsorption from primary urine and fine-tuning of body water homeostasis. Rho guanine nucleotide exchange factors (GEFs) interact with RhoA, catalyze the exchange of GDP for GTP and thereby activate the GTPase. However, GEFs involved in the control of AQP2 in renal principal cells are unknown. The A-kinase anchoring protein, AKAP-Lbc, possesses GEF activity, specifically activates RhoA, and is expressed in primary renal inner medullary collecting duct principal (IMCD) cells. Through screening of 18,431 small molecules and synthesis of a focused library around one of the hits, we identified an inhibitor of the interaction of AKAP-Lbc and RhoA. This molecule, Scaff10-8, bound to RhoA, inhibited the AKAP-Lbc-mediated RhoA activation but did not interfere with RhoA activation through other GEFs or activities of other members of the Rho family of small GTPases, Rac1 and Cdc42. Scaff10-8 promoted the redistribution of AQP2 from intracellular vesicles to the periphery of IMCD cells. Thus, our data demonstrate an involvement of AKAP-Lbc-mediated RhoA activation in the control of AQP2 trafficking

    The Scaff10 derivative Scaff10-8 binds to RhoA but not to the DHPH domain of AKAP-Lbc.

    No full text
    <p>(A-D) Microscale thermophoresis (MST) takes advantage of the phenomenon of directed movement of particles in a temperature gradient. Binding events lead to changes in the hydration shell of biomolecules and a relative change of movement of the molecular complex along a temperature gradient. Using such changes, binding affinities can be determined [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0191423#pone.0191423.ref047" target="_blank">47</a>]. MST assays were carried out with (A) the recombinant DHPH domain of AKAP-Lbc fused with GFP and RhoA as a ligand and (B) fluorescent 647-RhoA and the His-tagged AKAP-Lbc/DHPH domain as a ligand. (C) MST assays for the analysis of the binding of Scaff10-8 to 647-RhoA. Upper panels: The concentration of fluorescent 647-RhoA remained constant and Scaff10-8 (left) and Scaff10-7 as a negative control (right) were titrated in increasing concentrations. Lower panels: Values of fluorescence corresponding to upper panels. (D) MST assay showing no binding of Scaff10-8 or Scaff10-7 to GFP-DHPH. Upper panels: The concentration of fluorescent GFP-AKAP-Lbc/DHPH remained constant and Scaff10-8 (left) and Scaff10-7 (right) were titrated in increasing concentrations. Lower panels: Values of fluorescence corresponding to upper panels. The K<sub>D</sub> value for the binding of Scaff10-8 to 647-RhoA is 20 ± 11 μM. F norm = normalized fluorescence (fluorescence steady state/fluorescence initial state) indicated in ‰. n = 3–5. Mean ± SEM.</p
    corecore