Caracterizacion molecular del polimorfismo de las profilinas en el polen de olivo y otras especies alergogenicas

Resumen

Profilin are ubiquitous and multifuncional proteins which are present in numerous pollens. They play key roles in the regulation of the actin cytoskeleton and in the processes of cell signalling. In plants, they are encoded by multigenic families, showing a large number of isoforms or variants. profilins also have great interes as allergens. The present Ph.D. report analyzes profilin (Ole e 2 allergen) polymorphism in the pollen of the olive tree and other four species with allergenic potential (Betula pendula, Corylus avellana, Phleum pratense and Zea mays). This analysis was carried out by means of cellular and molecular techniques. profilin sequences from the pollen of a wide representation of the olive tree germoplasm (24 cultivars) were compared themselves, and also with those obtained from the others four species. All these sequences represent the basis for and extensive study carried out in silico, which includes the analysis of sequence conservation, structural stability, presence of posttraslatiional modifications, physicochemical properties and 3DStructure of the resulting proteins. Polymorphism has also been analyzed as regard to several parameters involved in the allergenic character, as are the presence of modifications in the antigenicity of the profilin molecule, or the presence of amino acid substitutions in the immunodominant epitopes involved in the recognition by T and B cells of the human immune system. The presence of polymorphism has been experimentally documented, and the differential reactivity of the different forms of profilin to several antibodies has been proved. Finally, cellular localization of profilin has been performed by usin transmission electron microscopy immunocitochemistry. Several of the antisera used showed differential localization of these proteins. In conclusion, the present study represents a wide screening of the molecular characteristics of the profilin in the olive pollen, and its comparison with those of other species, which allows us to predict numerous biological and clinical implications. The analytical determination of such implications can be clearly facilitated by this study.