CHANGES IN GENE-EXPRESSION DURING STRAWBERRY FRUIT RIPENING AND THEIRREGULATION BY AUXIN

Changes in messenger RNA during the development of the strawberry (Fra garia ananassa Duch.), a non-climacteric fruit. were analysed by extra cting total RNA and separating the in-vitro translated products by two -dimensional polyacrylamide gel electrophoresis. Alterations in numero us messenger RNAs accompanied fruit development between the immature g reen stage and the overripe stage, with prominent changes detected at or before the onset of ripening. A number of messenger RNAs undetectab le in immature green fruit increased as the fruit matured and ripened. Others showed a marked decrease in advance of the ripening phase. A f urther group of messenger RNAs was prominent in immature and ripe frui t but absent just prior to the turning stage. Removing the achenes fro m a segment of the fruit accelerated anthocyanin accumulation in the d e-achened portion and produced a pattern of translated polypeptides si milar to normal ripe fruit. Application of the synthetic auxin 1-napht haleneacetic acid to the de-achened receptacle produced a translation pattern similar to that in mature green fruit. These findings indicate that ripening in strawberry is associated with the expression of spec ific genes.