Utilization of tomato microarrays for comparative gene expression analysis in the Solanaceae.

Transcriptional profiling allows for the assessment and comparison of cross-species gene activity and function on a comprehensive scale. The Solanaceae is a large, diverse dicot family, with well-established genetic relationships between major crop species (tomato, potato, pepper, eggplant, and tobacco). Although Arabidopsis thaliana is often the model of choice for anchoring comparative studies, certain biological processes are better examined in other plants. The ripening of fleshy fruits is not tractable in Arabidopsis; however, it has received considerable attention in tomato. As a member of the Solanaceae, tomato provides a well-characterized system to anchor transcriptional profiles of fruit ripening and development in related species. By utilizing different stages of tomato, pepper, and eggplant fruit, the use of tomato microarrays for expression analysis has been demonstrated in closely related heterologous species, and groups of candidate expressed sequence tags, which are useful as orthologous markers, have been identified, as well as genes implicated in fruit ripening and development in the Solanaceae.