Identification of differentially expressed transcripts in peaches after harvest and heat treatment

LAUXMANN, MARTÍN ALEXANDER; PESSINO, SILVINA; LARA, MARÍA VALERIA; BUDDE, CLAUDIO OLAF; ANDREO, CARLOS SANTIAGO; DRINCOVICH, MARÍA FABIANA

Mar del Plata

Congreso; XLIII Reunión Anual de la Sociedad Argentina de Investigación en Bioquímica y Biología Molecular.; 2007

One goal in postharvest fruit technology is to increase the timebetween harvest and consumption. Fresh peaches are stored at 0ºCto preserve the quality and nutritional properties.Lowtemperaturesreduce enzymatic and microbial activity; diminish the respiratoryrate and the loss of water pressure. Nevertheless, under theseconditions, some varieties are affected by physiological disorderscalled chilling injury. The strategies for diminishing this injuryinclude heat treatment, among others, to maintain fruit quality andsafety. However, no conclusive research about the transcriptomeexpressed after this treatment have been performed. In the presentwork, the “differential display” technique has been applied toidentify differentially expressed transcripts in Dixiland peachesduring 3 or 7 days after harvest; as well as after 3 days at 39ºC andulterior ripening for 3 days at room temperature. After the heattreatment, the induction of transcripts related to the synthesis andresponse to auxin, as well as in the metabolism of reactive oxygenspecies, mRNA and phytochrome, were identified. On the otherhand, after 7 days of harvest a lipocalin transcript is induced, whichis repressed after heat treatment. The results obtained in the presentwork will help in the identification of the molecular factorsinvolved in the protection against chilling injury after heattreatment.