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  • ItemAcesso Aberto
    The w/w+ somatic mutation and recombination test (SMART) of Drosophila melanogaster for detecting antigenotoxic activity
    2020-03-12 - Gaivão, Isabel O Neill de Mascarenhas; Ferreira, João; Sierra, Luisa María
    Genotoxicological studies are emerging as fundamental for knowing the hazards to our genome, to our health. Drosophila melanogaster is one of the preferable organisms for toxicological research considering its metabolic similarities (viz. on dietary input, xenobiotic metabolizing system, antioxidant enzymes and DNA repair systems) to mammals. Accordingly, somatic mutation and recombination tests (SMARTs) of D. melanogaster are fast and low-cost in vivo assays that have shown solid results evaluating genotoxicity. The w/w+ SMART uses the white (w) gene as a recessive marker to monitor the presence of mutant ommatidia (eye units), indicating the occurrence of point mutations, deletions, mitotic recombination or/and nondisjunction. Additionally, several studies used SMARTs to assess antigenotoxicity, with some using the w/w+ SMART. We reviewed the state of the art of the w/w+ SMART used for antigenotoxicity analysis, focusing on published results, aiming to contribute to the conception of a reliable protocol in antigenotoxicity. As such, genotoxic agents with known action mechanisms, as streptonigrin (oxidative stress inducer), were used as a genotoxic insult for proving the antigenotoxic effects of natural substances (e.g. seaweeds), demonstrating the presence of antimutagens in their composition. These antigenotoxicity studies are crucial for promoting preventive measures against environmental genotoxics that affect humans daily.
  • ItemAcesso Aberto
    Apple (Malus spp.) Breeding: Present and Future
    2018 - Pereira-Lorenzo, Santiago; Fischer, Manfred; Ramos-Cabrer, Ana María; Castro, Isaura Alberta Oliveira De
    Apple breeding has been extremely successful in providing a highly diverse fruit crop. Recent (>50 millions years ago) genome-wide duplication (GWD) resulted in the 17 chromosomes in the Pyreae and confirmed the origin of cultivated apple on Malus sieversii being the same species as M. × domestica. Malus, as many other species in the family Rosaceae, shows gametophytic self-incompatibility (GSI), which forces outcrossing. GSI at the pistil is regulated by extacellular ribonuclease, S-RNase, which is encoded by S locus. Growers and agronomists have provided multiple cultivars with different colors, shapes, resistances, climatic adaptation or industrial aptitudes. The aim in apple breeding was the combination of different kinds of resistance and good fruit quality to produce dessert cultivars and cultivars for processing. Some of the best of these cultivars display resistance to scab (Venturia inaequalis), mildew (Podosphaera leucotricha), fire blight (Erwinia amylovora), bacterial canker (Pseudomonas syringae), red spider mite (Panonychus ulmi), winterfrost and good fruit quality. Different scab resistance sources of wild species (Vf, Vr, VA) were combined in the new series of cultivars. Multiple efforts worldwide have conserved most of that variation, the pillar for the traditional and new techniques profiting from the analysis of the apple genome, the genome-wide association studies (GWAS), identifying SNPs and genes, the analysis of genes differentially expressed (GDE) identified by qRT-PCR and microarray analysis, and the recent molecular genetic tool CRISPR/Cas9 to edit and correct the genome.
  • ItemAcesso Aberto
    Olive tree genetic resources characterization through molecular markers
    2012 - Gomes, Sónia; Martins-Lopes, Paula; Guedes-Pinto, Henrique
  • ItemAcesso Restrito
    Olive - Colletotrichum acutatum: an example of fruit-fungal Interaction
    2012 - Gomes, Sónia; Prieto, Pilar; Carvalho, Teresa; Guedes-Pinto, Henrique; Martins-Lopes, Paula
  • ItemAcesso Restrito
    Olive Oil Traceability through DNA Markers
    2012 - Martins-Lopes, Paula; Gomes, Sónia
  • ItemAcesso Aberto
    Banding for Chromosomal Identification in Bivalves: A 20-year History
    2008 - Chaves, Raquel; Leitão, Alexandra