Search results for "SCA"

Structural and transcriptional evidence of mechanotransduction in the Drosophila suzukii ovipositor

2020

Drosophila suzukii is an invasive pest that prefers to lay eggs in ripening fruits, whereas most closely related Drosophila species exclusively use rotten fruit as oviposition site. This behaviour is allowed by an enlarged and serrated ovipositor that can pierce intact fruit skin, and by multiple contact sensory systems (mechanosensation and taste) that detect the optimal egg-laying substrates. Here, we tested the hypothesis that bristles present in the D. suzukii ovipositor tip contribute to these sensory modalities. Analysis of the bristle ultrastructure revealed that four different types of cuticular elements (conical pegs type 1 and 2, chaetic and trichoid sensilla) are present on the t…

Effects of the temporal scale of observation on the analysis of aquatic invertebrate metacommunities

2020

The development of metacommunity theory has boosted the implementation of numerous empirical tests with field data, mostly focused on the role of spatial and environmental gradients on metacommunity organization. These studies showed an important dependence of the results on the observational scale considered, i.e., spatial grain, sampling spacing, and extent. However, few works deal with time per se as a component explaining metacommunity structure, even when data from periodic sampling are available. We suggest adding time explicitly to metacommunity analysis, but taking into account that the temporal scale of observation could affect the estimation of the relative influence of environmen…

The Nonbilayer Lipid MGDG and the Major Light-Harvesting Complex (LHCII) Promote Membrane Stacking in Supported Lipid Bilayers.

2018

The thylakoid membrane of algae and land plants is characterized by its intricate architecture, comprising tightly appressed membrane stacks termed grana. The contributions of individual components to grana stack formation are not yet fully elucidated. As an in vitro model, we use supported lipid bilayers made of thylakoid lipid mixtures to study the effect of major light-harvesting complex (LHCII), different lipids, and ions on membrane stacking, seen as elevated structures forming on top of the planar membrane surface in the presence of LHCII protein. These structures were examined by confocal laser scanning microscopy, atomic force microscopy, and fluorescence recovery after photobleachi…

Patterns of genetic diversity and structure in Antarctic and sub-Antarctic Nacella (Patellogastropoda: Nacellidae) species.

2016

10 pages; International audience; The biogeography of the Southern Ocean reflects complex interactions between major macro-evolutionary forces and biotic elements. Major gateway openings, the establishment of the Antarctic Circumpolar Current and climate cooling are deeply connected to the composition, abundance and distribution of the Southern Ocean marine benthic fauna. Glacial episodes of the Quaternary heavily impacted the distribution of the genetic variation of the Southern Ocean biota. The genus Nacella includes 12 nominal species in different provinces of the Southern Ocean. In this study, we compared patterns of mitochondrial DNA diversity in three Nacella species from Antarctic Pe…

2017

Both effective population size and life history may influence the efficacy of purifying selection, but it remains unclear if the environment affects the accumulation of weakly deleterious nonsynonymous polymorphisms. We hypothesize that the reduced energetic cost of osmoregulation in brackish water habitat may cause relaxation of selective constraints at mitochondrial oxidative phosphorylation (OXPHOS) genes. To test this hypothesis, we analyzed 57 complete mitochondrial genomes of Pungitius pungitius collected from brackish and freshwater habitats. Based on inter- and intraspecific comparisons, we estimated that 84% and 68% of the nonsynonymous polymorphisms in the freshwater and brackish …

Microalgae, old sustainable food and fashion nutraceuticals.

2017

8 p.-1 fig.

Impact of gas emboli and hyperbaric treatment on respiratory function of loggerhead sea turtles (Caretta caretta)

2018

We investigated lung function in bycaught sea turtles with and without gas emboli. Hyperbaric O2 treatment significantly improves lung function. Pulmonary function testing may be a useful diagnostic tool to assess fisheries induced trauma.

Highly contrasted population genetic structures in a host-parasite pair in the Caribbean Sea.

2017

Evolution and population genetic structure of marine species across the Caribbean Sea are shaped by two complex factors: the geological history and the present pattern of marine currents. Characterizing and comparing the genetic structures of codistributed species, such as host–parasite associations, allow discriminating the relative importance of environmental factors and life history traits that influenced gene flow and demographic events. Using microsatellite and Cytochrome Oxidase I markers, we investigated if a host–parasite pair (the heart urchin Meoma ventricosa and its parasitic pea crab Dissodactylus primitivus) exhibits comparable population genetic structures in the Caribbean Sea…

Genetic analysis of goldsinny wrasse reveals evolutionary insights into population connectivity and potentialevidence of inadverent translocationvia …

2017

The salmon industry is heavily dependent on wrasse for delousing infected fish. The goldsinny wrasse is numerically the most important, and each year, millions are harvested from the wild and transported large distances into fish farms. Population genetic knowledge is required to sustainably exploit this species. Here, 1051 goldsinny wrasses from 16 locations across Scandinavia, the British Isles, and Spain were genotyped with 14 microsatellite and 36 SNP markers. Within-population genetic diversity decreased towards north, and a genetic break was observed across the North Sea. Samples from Northern Norway differed from rest of the Scandinavian samples, and samples from the British Isles di…

North African hybrid sparrows (Passer domesticus, P. hispaniolensis) back from oblivion – ecological segregation and asymmetric mitochondrial introgr…

2016

A stabilized hybrid form of the house sparrow (Passer domesticus) and the Spanish sparrow (P. hispaniolensis) is known as Passer italiae from the Italian Peninsula and a few Mediterranean islands. The growing attention for the Italian hybrid sparrow and increasing knowledge on its biology and genetic constitution greatly contrast the complete lack of knowledge of the long-known phenotypical hybrid sparrow populations from North Africa. Our study provides new data on the breeding biology and variation of mitochondrial DNA in three Algerian populations of house sparrows, Spanish sparrows, and phenotypical hybrids. In two field seasons, the two species occupied different breeding habitats: Spa…