ANÁLISIS DE EXPRESIÓN DE GENES CODIFICANTES DE ISOENZIMAS DE RAMNOGALACTURONANO LIASA DURANTE EL DESARROLLO Y LA MADUREZ DEL FRUTO DE TOMATE

Resumen

Tomato cultivation generates great profits for Mexico; however, the distribution of the fruit faces limitations due to the postharvest losses caused by its rapid deterioration. The reduction in fruit firmness is due in part to the degradation of pectin located in the primary cell wall. Several fruits such as strawberry (Fragaria × ananassa), tomato (Solanum lycopersicum L.) and mango (Mangifera indica L.) show an increase in the expression of genes that code for the enzyme rhamnogalacturonan lyase (RGL) during ripening. In tomato RGL is encoded by a family of 13 multigenes, of which three are active in the fruit. Rhamnogalacturonan l (RG-l) is a polysaccharide that is part of the pectins of the cell wall and is degraded by the RGL enzyme. Thus, the study of changes of RGL in the expression of genes that code for RGL during the development and ripening of tomato fruit will help to elucidate the physiological function of this family of genes. The objective of the present study was to assess the expression profile of genes Solyc04g076630, Solyc04g076660 and Solyc11g011300 and the ethylene production during the development and ripening of the tomato fruit. The Solyc11g011300 gene showed an increase in activity that correlated with the increase in ethylene production in fruits, suggesting that this gene plays a role in the loss of firmness of the fruit during ripening. The high levels of expression of genes Solyc04g076630 and Solyc04g076660 recorded during fruit development suggest their participation in the re-engineering of the RG-I polymer during the initial stages of fruit development.