A b-xylosidase gene could act as good indicator of tolerance to chilling injury in peach fruit

BUSTAMANTE, CLAUDIA; GENERO, MELINA; GISMODI, MAURO; MONTI, LAURA; GABILONDO, JULIETA; BUDDE, CLAUDIO OLAF; LARA, MARÍA VALERIA; DRINCOVICH, MARÍA FABIANA

Rosario

Congreso; L Reunión Anual de la Sociedad Argentina de Investigación Bioquímica y Biología Molecular; 2014

Sociedad Argentina de Investigación Bioquímica y Biología Molecular

The storage of peaches at low temperatures for prolonged periods can induce a form of chilling injury (CI) called woolliness, characterized by a lack of juiciness and a mealy texture. As this disorder has been associated with abnormal cell wall dismantling, resistant (Springlady), intermediate (Rojo2) and susceptible (Flordaking) cultivar were selected to study the levels of twelve transcripts encoding proteins involved in cell wall metabolism. Of all cell wall-related genes studied, only PpXyl1, which encodes a putative B-Xylosidase, seems to act as good indicator of tolerance to CI, as its expression correlated with the different susceptibility to this disorder after cold storage. PpXyl full length was cloned and sequenced in the three cultivars in order to look for changes in PpXyl that may alter the capacity function of the protein. In addition, a fragment of 1637 bp, corresponding to the promoter region of the gene, was isolated form Springlady, Rojo 2 and Flordaking genomic DNA in order to investigate the presence of putative regulatory sequences that may be responsible for the differential patterns of expression. The presence of cis-acting elements associated with hormone and stress-related responses, along with the results obtained in this work, suggest a role of PpXyl in determining different tolerance to CI in peach fruit.