STRAWBERRY ON CHIPS: FROM GENE EXPRESSION TO METABOLIC PATHWAYS

¹ Department of Cell Biology, Center for Plant Breeding and Reproduction Research (CPRO), Wageningen, The Netherlands

² Centre for Biometry, Wageningen, The Netherlands

³ Department of Biochemistry, Beckman Center, Stanford University Medical Center, Stanford, California 94305, USA

Fruits are an important part of our diet mainly as a source of energy, vitamins and minerals in addition to their aesthetic qualities. Fruit development and ripening is a complex biological process involving the co-ordinated regulation of genes and biochemical pathways leading to key processes such as color, softening and flavor. Physical and morphological changes are often a result of changes in protein levels and activities, which may reflect shifts in overall mRNA abundance. Microarray technology provides a powerful tool for following temporal changes in mRNA levels through large scale expression profiling of genes. Using high-speed robotics 1700 cDNAs picked randomly from a strawberry fruit cDNA library were spotted in high density on glass microscope slides. The arrays were used for parallel hybridization of fluorecently labeled mRNA populations. The first set of experiments included the analysis of strawberry gene expression during fruit development from green to red ripe fruit. Novel genes were identified which through their expression profiles could be correlated with specific metabolic processes. Specific genes were further characterized and subsequent proof of function obtained. The results validate the capability of the system to provide quantitative and accurate chronological data, to link gene to function, which will no doubt aid future plant functional genomics research.