Search results for "Molecular"

Local adaptation of plant viruses: lessons from experimental evolution.

2016

[EN] For multihost pathogens, adaptation to multiple hosts has important implications for both applied and basic research. At the applied level, it is one of the main factors determining the probability and severity of emerging disease outbreaks. At the basic level, it is thought to be a key mechanism for the maintenance of genetic diversity both in host and pathogen species. In recent years, a number of evolution experiments have assessed the fate of plant virus populations replicating within and adapting to one single or to multiple hosts species. A first group of these experiments tackled the existence of trade-offs in fitness and virulence for viruses evolving either within a single hos…

The nucleotide sequence of a recombinant tomato yellow leaf curl virus strain frequently detected in Sicily isolated from tomato plants carrying the …

2017

In July 2016, an aggressive syndrome of tomato yellow leaf curl disease was reported in Sicily in tomato plants carrying the Ty-1 resistance gene. A total of 34 samples were collected and analyzed. Twenty-seven out of the 34 samples analyzed appeared to contain only recombinant molecules. One full sequence was obtained after cloning. Alignments and plot similarity analysis showed that the genome of the recombinant, named TYLCV-IL[IT:Sic23:16], was mostly derived from tomato yellow leaf curl virus (TYLCV), with a small region of 132 nucleotides in the non-coding region between the stem-loop and the start of the V2 ORF replaced by 124 nucleotides derived from a virus of a different species, t…

The legacy of a vanished sea: a high level of diversification within a European freshwater amphipod species complex driven by 15 My of Paratethys reg…

2016

16 pages; International audience; The formation of continental Europe in the Neogene was due to the regression of the Tethys Ocean and of the Paratethys Sea. The dynamic geology of the area and repetitious transitions between marine and freshwater conditions presented opportunities for the colonization of newly emerging hydrological networks and diversification of aquatic biota. Implementing mitochondrial and nuclear markers in conjunction with a large-scale sampling strategy, we investigated the impact of this spatiotemporal framework on the evolutionary history of a freshwater crustacean morphospecies. The Gammarus balcanicus species complex is widely distributed in the area previously oc…

Lipid Nanoparticles as Potential Gene Therapeutic Delivery Systems for Oral Administration.

2017

Background Gene therapy has experimented an increasing attention in the last decades, due to its enormous potential applications in the medical field. It can be defined as the use of genes or genetic material (DNA, RNA, oligonucleotides) to treat or prevent a disease state, generally a geneticbased one. Application Other applications, like treating viral, bacterial or parasite infections or development of vaccines are gaining also interest. Efficient gene therapy is mainly dependent on the ability of the highly labile genetic material to reach the therapeutic target. For this purpose, different delivery systems have been designed and extensively investigated. Nanoparticles offer a broad ran…

Selective sweep ofWolbachiaand parthenogenetic host genomes - the example of the weevilEusomus ovulum

2016

Most parthenogenetic weevil species are postulated to have originated via hybridization, but Wolbachia has also been speculated to play a role via the induction of parthenogenesis. Here, we examine the molecular diversity of Wolbachia and parthenogenetic host genomes. The host species studied here, Eusomus ovulum, is known to be exclusively parthenogenetic and triploid. The E. ovulum populations that we examined had a low genetic diversity of mitochondrial (cytochrome oxidase I gene) and nuclear markers (internal transcribed spacer 2 and elongation factor 1-α gene), and they all were infected by only single bacteria strains (genotyped for five genes according to the multilocus sequence typi…

2017

Targeted high-throughput sequencing using hybrid-enrichment offers a promising source of data for inferring multiple, meaningfully resolved, independent gene trees suitable to address challenging phylogenetic problems in species complexes and rapid radiations. The targets in question can either be adopted directly from more or less universal tools, or custom made for particular clades at considerably greater effort. We applied custom made scripts to select sets of homologous sequence markers from transcriptome and WGS data for use in the flowering plant genus Erica (Ericaceae). We compared the resulting targets to those that would be selected both using different available tools (Hyb-Seq; M…

cDNA sequences of two arylphorin subunits of an insect biliprotein: phylogenetic differences and gene duplications during evolution of hexamerins-imp…

2016

Arylphorins represent a conserved class of hexameric ∼500 kDa insect hemolymph glycoproteins, rich in aromatic amino acids, which are produced in large quantities at the larval stage as reserves for metamorphosis and egg development. The recently isolated arylphorin from the moth Cerura vinula is unique in being complexed to a novel farnesylated bilin. Protein sequencing suggested the presence of two different ∼85 kDa subunits. Here, we report the complete coding sequences of two cDNAs encoding two arylphorins subunits with 67% identity and calculated physicochemical characteristics in agreement with the isolated holoprotein. Our phylogenetic analyses of the hexamerins revealed monophyletic…

Chironomus riparius(Diptera) genome sequencing reveals the impact of minisatellite transposable elements on population divergence

2016

AbstractActive transposable elements (TEs) may result in divergent genomic insertion and abundance patterns among conspecific populations. Upon secondary contact, such divergent genetic backgrounds can theoretically give rise to classical Dobzhansky-Muller incompatibilities (DMI), a way how TEs can contribute to the evolution of endogenous genetic barriers and eventually population divergence. We investigated whether differential TE activity created endogenous selection pressures among conspecific populations of the non-biting midgeChironomus riparius,focussing on aChironomus-specific TE, the minisatellite-likeCla-element, whose activity is associated with speciation in the genus. Using an …

The complete plastid genome of the middle Asian endemic of Stipa lipskyi (Poaceae)

2016

AbstractThe structure of the Stipa lipskyi (GenBank accession no. KT692644) plastid genome is similar to that of closely related Poaceae species: it has a total length of 137 755 bp, the base composition of the plastome is the following: A (30.7%), C (19.3%), G (19.4%) and T (30.5%). The S. lipskyi plastid genome contains 71 genes, excluding second IR region. A complete plastome sequence of S. lipskyi will help the development of primers for examining phylogeny and hybridization events in this taxonomically difficult genus.

S-genotype identification, genetic diversity and structure analysis of Italian sweet cherry germplasm

2017

In this study, 186 local sweet cherry accessions from 12 Italian regions, plus eight reference accessions, were analysed for the first time, using 13 microsatellite markers. Moreover, their S-incompatibility genotypes were identified with consensus primers for the S-RNase and SFB genes. A total of 161 unique genotypes were found; 18 groups of synonyms, along with the discovery of cases of misidentification. The average number of alleles per locus was 9.7, the mean expected heterozygosity (He) was 0.63, the mean observed heterozygosity (Ho) was 0.65 and the mean polymorphic information content (PIC) was 0.58. The structure analysis revealed the presence of six populations, which reflected in…