alfa-Arabinofuranosidase (alfa-Ara) in strawberry fruit: Enzyme activity and expression of related genes in cultivars with contrasting firmness

ROSLI HERNAN; CIVELLO PEDRO; MARTINEZ GUSTAVO

Pinamar, Argentina

Congreso; XLI Reunión Anual de SAIB (Sociedad Argentina de Investigación en Bioquímica y Biología Molecular); 2005

SAIB

Fruit softening is accompanied by cell wall modification leading to solubilization and depolimerization of its components. This modification is mediated by several proteins. Arabinose is the most abundant neutral sugar in strawberry and it is also the one showing the largest decrease during ripening. á-ARA catalyzes the hydrolysis of arabinose residues present in pectins and hemicelluloses side chains. In this work we analysed á-ARA activity during ripening of strawberry cultivars with contrasting fruit firmness. The softest cultivar showed higher activity levels and increased throughout ripening. A partial purification was run in a sephacryl S100column and a peak corresponding to 70KDa was found. We screened a ripe fruit cDNA library using degenerate primers and found three putative á-ARA full length clones. Semi quantitative RT-PCRs were carried out to investigate expression of these genes during fruit ripening and in different tissues.