Cloning of two putative polygalacturonase genes and analysis of their expression during ripening of strawberry cultivars with contrasting fruit firmness

VILLARREAL NATALIA; MARTINEZ GUSTAVO; CIVELLO PEDRO

Pinamar, Argentina

Congreso; 10th Congress of PABMB (Panamerican Association for Biochemistry and Molecular Biology); 2005

SAIB

During fruit ripening, cell wall polymers suffer modifications as a consequence of the coordinated action of a range of enzymes. Polygalacturonases (PGs) are hydrolases involved in pectin degradation during ripening of fleshy fruits, as strawberry. In order to obtain the full length sequence corresponding to partial PG clones previously isolated from strawberry fruits, a RACE reaction was performed with the BD SmartTM RACE cDNA Amplification Kit (Clontech). In the present work, we report the cloning of two putative polygalacturonase full length genes: FaPG and PGX8, from strawberry fruits of Camarosa cultivar. PgX8 has a deletion of 85 bp and a possible frame shift that would produce an inactive protein. By Semiquantitative RT-PCR we have analyzed the expression pattern of both genes on three strawberry cultivars with contrasting fruit firmness. Our results show that PGs expression is different in each cultivar. The expression of PGX8 is higher in the firm than in the soft cultivars, while the opposite occurs in the case of FaPG.