Search results for "gene transfer"

The evolutionary genetics of the hobo transposable element in the Drosophila melanogaster complex.

1994

Hobo elements are a family of transposable elements found in Drosophila melanogaster and its three sibling species: D. simulans, D. mauritiana and D. sechellia. Studies in D. melanogaster have shown that hobo may be mobilized, and that the genetic effects of such mobilizations included the general features of hybrid dysgenesis: mutations, chromosomal rearrangements and gonadal dysgenis in F1 individuals. At the evolutionary level some hobo-hybridizing sequences have also been found in the other members of the melanogaster subgroup and in many members of the related montium subgroup. Surveys of older collected strains of D. melanogaster suggest that complete hobo elements were absent prior t…

What is in a lichen? A metagenomic approach to reconstruct the holo-genome of Umbilicaria pustulata

2019

AbstractLichens are valuable models in symbiosis research and promising sources of biosynthetic genes for biotechnological applications. Most lichenized fungi grow slowly, resist aposymbiotic cultivation, and are generally poor candidates for experimentation. Obtaining contiguous, high quality genomes for such symbiotic communities is technically challenging. Here we present the first assembly of a lichen holo-genome from metagenomic whole genome shotgun data comprising both PacBio long reads and Illumina short reads. The nuclear genomes of the two primary components of the lichen symbiosis – the fungus Umbilicaria pustulata (33 Mbp) and the green alga Trebouxia sp. (53 Mbp) – were assemble…

Improving mRNA-Based Therapeutic Gene Delivery by Expression-Augmenting 3' UTRs Identified by Cellular Library Screening.

2019

Synthetic mRNA has emerged as a powerful tool for the transfer of genetic information, and it is being explored for a variety of therapeutic applications. Many of these applications require prolonged intracellular persistence of mRNA to improve bioavailability of the encoded protein. mRNA molecules are intrinsically unstable and their intracellular kinetics depend on the UTRs embracing the coding sequence, in particular the 3′ UTR elements. We describe here a novel and generally applicable cell-based selection process for the identification of 3′ UTRs that augment the expression of proteins encoded by synthetic mRNA. Moreover, we show, for two applications of mRNA therapeutics, namely, (1) …

Capillary enlargement, not sprouting angiogenesis, determines beneficial therapeutic effects and side effects of angiogenic gene therapy.

2010

Aims Currently, it is still unclear which mechanisms drive metabolic benefits after angiogenic gene therapy. The side-effect profile of efficient angiogenic gene therapy is also currently incompletely understood. In this study, the effects of increasing doses of adenoviral (Ad) vascular endothelial growth factor-A (VEGF-A) were evaluated on vascular growth, metabolic benefits, and systemic side effects. Methods and results Adenoviral vascular endothelial growth factor-A or AdLacZ control was injected intramuscularly (109–1011 vp/mL) or intra-arterially (5 × 1011 vp/mL) into rabbit ( n = 102) hindlimb muscles and examined 6 or 14 days later. Blood flow, tissue oedema, metabolic benefits, and…

ViR: a tool to account for intrasample variability in the detection of viral integrations

2020

ABSTRACTLateral gene transfer (LT) from viruses to eukaryotic cells is a well-recognized phenomenon. Somatic integrations of viruses have been linked to persistent viral infection and genotoxic effects, including various types of cancer. As a consequence, several bioinformatic tools have been developed to identify viral sequences integrated into the human genome. Viral sequences that integrate into germline cells can be transmitted vertically, be maintained in host genomes and be co-opted for host functions. Endogenous viral elements (EVEs) have long been known, but the extent of their widespread occurrence has only been recently appreciated. Modern genomic sequencing analyses showed that e…

Molecular Mechanisms Involved in the Adaptive Evolution of Industrial Yeasts

2006

Functional characterization of the sea urchin sns chromatin insulator in erythroid cells.

2005

Abstract Chromatin insulators are regulatory elements that determine domains of genetic functions. We have previously described the characterization of a 265 bp insulator element, termed sns, localized at the 3′ end of the early histone H2A gene of the sea urchin Paracentrotus lividus. This sequence contains three cis-acting elements (Box A, Box B, and Box C + T) all needed for the enhancer-blocking activity in both sea urchin and human cells. The goal of this study was to further characterize the sea urchin sns insulator in the erythroid environment. We employed colony assays in human (K562) and mouse (MEL) erythroid cell lines. We tested the capability of sns to interfere with the communi…

Bracovirus derived genes in the genome of Spodoptera exigua Hubner (Lepidoptera: Noctuidae) and their role in host susceptibility to pathogens

2015

La asociación entre los himenópteros parasitoides, polydnavirus (PDV) y lepidópteros representa un modelo interesante para estudiar la transferencia horizontal de genes. Está bien documentado que miles de himenópteros parasitoides pertenecientes a las familias Braconidae e Ichneumonidae han domesticado virus simbióticos denominados respectivamente Bracovirus o Ichnovirus. El virus se inyecta junto con los huevos del parásito en el hemocele del lepidóptero huésped, donde se expresan proteínas específicas. Estas proteínas inhiben el sistema inmune del lepidóptero y detienen su desarrollo, lo que beneficia el desarrollo de los huevos y luego las larvas del parasitoide. En este sistema único, t…

Genome rearrangement distances and gene order phylogeny in gamma-Proteobacteria.

2005

Genome rearrangements have been studied in 30 gamma-proteobacterial complete genomes by comparing the order of a reduced set of genes on the chromosome. This set included those genes fulfilling several characteristics, the main ones being that an ortholog was present in every genome and that none of them had been acquired by horizontal gene transfer. Genome rearrangement distances were estimated based on either the number of breakpoints or the minimal number of inversions separating two genomes. Breakpoint and inversion distances were highly correlated, indicating that inversions were the main type of rearrangement event in gamma-Proteobacteria. In general, the progressive increase in seque…

Preceding Host History of Conjugative Resistance Plasmids Affects Intra- and Interspecific Transfer Potential from Biofilm

2023

Conjugative plasmids can confer antimicrobial resistance (AMR) to their host bacterium. The plasmids disperse even between distantly related host species, rescuing the host from otherwise detrimental effects of antibiotics. Little is known about the role of these plasmids in the spread of AMR during antibiotic treatment. One unstudied question is whether the past evolutionary history of a plasmid in a particular species creates host specificity in its rescue potential or if interspecific coevolution can improve interspecific rescues. To study this, we coevolved the plasmid RP4 under three different host settings; solely Escherichia coli or Klebsiella pneumoniae, or alternating between both …