Biomedical subjects

F De Marchis

Publications and source records attributed to F De Marchis.

4 recordsLinked to original sources

PubMed2005

cDNA AFLP-based techniques for studying transcript profiles in horses.

The identification of differentially expressed genes is a fundamental prerequisite for understanding the molecular regulation of most physiological and pathological processes. Among the procedures employed to compare mRNA populations, those that are gel-based appear to hold great promise and are considered excellent tools for studying gene expression in species, such as the equine one, for which little genomic information is available. In the present study, we evaluated two techniques for studying mRNA profiles in horse tissue, one referred to the cDNA-amplified fragment length polymorphism (AFLP) that we called C-AFLP (classical cDNA-AFLP) protocol and the other to ordered differential display (ODD) with some modifications that we named S-AFLP (systematic cDNA-AFLP). Both techniques can be applied in live animals because of the small amount of sample required. We applied the S-AFLP to investigate horse transcript profile modifications during physical exercise. We found two transcripts that are mostly expressed during exercise and immediately after the end of it.

Animals↗

PubMed2003

Jellyfish green fluorescent protein as a useful reporter for transient expression and stable transformation in Medicago sativa L.

The aim of the experiments reported herein was to transiently test different gene constructs using green fluorescent protein (GFP) as a reporter gene for a future localization of the maize beta-zein in the chloroplast of alfalfa ( Medicago sativa L.). The transient expression of two GFP genes was compared in alfalfa leaves to determine which of these two mutants is the easier to detect. Based on the intensity of fluorescence emitted, the GFP S65C gene was used to assemble a chloroplast-targeted GFP to verify the efficiency of the transit peptide for chloroplast targeting. A chloroplast-targeted fusion protein between beta-zein and GFP was then assembled, and this protein was observed to accumulate in small aggregates into the chloroplasts of transiently transformed cells. To the best of our knowledge, this is the first report of the GFP S65C gene being used to obtain transformed alfalfa plants expressing GFP.

Chloroplasts↗

PubMed2003

Measuring gene flow from two birdsfoot trefoil (Lotus corniculatus) field trials using transgenes as tracer markers.

Genetic engineering is becoming a useful tool in the improvement of plants but concern has been expressed about the potential environmental risks of releasing genetically modified (GM) organisms into the environment. Attention has focused on pollen dispersal as a major issue in the risk assessment of transgenic crop plants. In this study, pollen-mediated dispersal of transgenes via cross-fertilization was examined. Plants of Lotus corniculatus L. transformed with either the Escherichia coli asparagine synthetase gene asnA or the beta-glucuronidase gene uidA, were used as the pollen donor. Nontransgenic plants belonging to the species L. corniculatus L., L. tenuis Waldst. and Kit. ex Willd, and L. pedunculatus Cav., were utilized as recipients. Two experimental fields were established in two areas of central Italy. Plants carrying the uidA gene were partially sterile, therefore only the asnA gene was used as a tracer marker. No transgene flow between L. corniculatus transformants and the nontransgenic L. tenuis and L. pedunculatus plants was detected. As regards nontransgenic L. corniculatus plants, in one location flow of asnA transgene was detected up to 18 m from the 1.8 m2 donor plot. In the other location, pollen dispersal occurred up to 120 m from the 14 m2 pollinating plot.

Aspartate-Ammonia Ligase↗

PubMed2000

The chemotactic and mitogenic effects of platelet-derived growth factor-BB on rat aorta smooth muscle cells are inhibited by basic fibroblast growth factor.

In response to endovascular injury, platelet-derived growth factor-BB (PDGF-BB) and basic fibroblast growth factor (bFGF) are released locally and modulate vascular smooth muscle cells (SMC) proliferation and migration within the vascular wall. The aim of the present in vitro study was to determine how rat aorta SMC respond to the simultaneous exposure to PDGF-BB and bFGF. In a modified Boyden chamber assay bFGF exhibited a dose-dependent effect to inhibit the chemotactic action of PDGF-BB. A comparable result was observed in proliferation assays. In contrast, MIP-1 beta, epidermal growth factor (EGF), fibronectin and acidic FGF (aFGF) did not inhibit the chemotactic effect of PDGF-BB. Denatured bFGF did not exert an inhibitory effect and neutralizing antibodies either to bFGF or to bFGF-receptor abolished the inhibition observed in the presence of bFGF. The role played by PDGF receptor alpha (PDGF-Ralpha) was investigated in PDGF-Ralpha-dominant negative-transfected SMC, by selectively blocking PDGF-BB-binding to PDGF-Ralpha with neomycin, by neutralizing PDGF-Ralpha with a monoclonal antibody and by selectively stimulating PDGF-Ralpha with PDGF-AA; in all cases the effect of bFGF to inhibit PDGF-BB-directed SMC migration was abolished. These in vitro studies show that bFGF significantly inhibits PDGF-BB-induced SMC migration and proliferation and that this effect is mediated by both PDGF-Ralpha and bFGF receptor.

Animals↗