Submitted to: Journal of Experimental Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/28/2002
Publication Date: 10/1/2002
Citation: MOORE, S., VREBALOV, J., PAYTON, P., GIOVANNONI, J.J. USE OF GENOMICS TOOLS TO ISOLATE KEY RIPENING GENES AND ANALYZE FRUIT MATURATION IN TOMATO. JOURNAL OF EXPERIMENTAL BOTANY. 2002. V. 53. P. 2023-2030. Interpretive Summary: The increasing availability of efficient, high-throughput methodologies for cloning and sequencing have driven the development of novel discovery platforms able to exploit the increasing amounts of available genome data. Until recently, significant gene sequence and functional data for a given biological system was virtually non-existent or the result of painstakingly piecing together studies conducted over many years utilizing classical approaches. New methodologies now allow for the expansion of traditional platforms of utilizing forward and reverse genetics to those that facilitate examination of behavior of hundreds or thousands of genes simultaneously. In tomato, a collaborative NSF funded effort has resulted in the construction and sequencing of cDNA libraries from a multitude of tissues and conditions, and the creation of a tomato EST database. This information provides the foundation for parallel gene studies for detection and quantitation of gene expression levels. Parallel studies can provide both static (e.g. examination of gene expression in a single tissue) and dynamic (comparative) information. We report here a summary of these tools in tomato and their initial use to isolate and characterize tomato ripening mutants.
Technical Abstract: Molecular and genetic analysis of fruit development, and especially ripening of fleshy fruits, has resulted in significant gains in knowledge over recent years, especially with respect to understanding ethylene biosynthesis and response, cell wall metabolism, and to a lesser extent, environmental cues which impact ripening. Tomato has proved to be an excellent model system for analysis of fruit ripening and development in part due to the availability of well characterized ripening mutants. Especially interesting are the ripening-inhibitor (rin) and non-ripening (nor) mutations which result in non-ripening fruit. Fruit from both non-allelic mutations are deficient in climacteric respiration and the associated burst in ethylene biosynthesis. Both mutations represent genes upstream of ethylene control and additional non-ethylene mediated aspects of ripening. We have recently isolated both genes through positional cloning strategies and demonstrate that ripening is regulated in part by a MADS-box transcription factor at the rin locus. Recent development of tools for tomato genomics summarized here have further expanded the potential of the tomato system for elucidation of genetic regulatory components impacting fruit development, ripening and nutritional quality.