Submitted to: National Center for Biotechnology Information (NCBI)
Publication Type: Research Notes
Publication Acceptance Date: 11/21/2005
Publication Date: 9/1/2006
Citation: Levi, A., Davis, A.R., Hernandez, A., Wechter, W.P., Thimmapuram, J. 2006. Sequence Analysis of CDNA Clones Associated with Watermelon Fruit Development. National Center for Biotechnology Information (NCBI). http://www.ncbi.nlm.nih.gov/entrez Interpretive Summary: Watermelon is a major vegetable crop grown in 44 states in the U.S. In recent years, there has been an increased demand for seedless watermelon, and a great interest by consumers in the naturally occurring carotenoid pigments in watermelon. Carotenoids are known to be a main dietary source of vitamin A in humans, and are associated with reduced risk of several chronic health disorders including some forms of cancer, heart disease and eye degeneration. Developing watermelon cultivars with increased carotenoid levels will benefit consumer health. However, there is insufficient information about the genes that control fruit quality, particularly the genes controlling carotenoid production in watermelon. This study identifies and examines the sequences of genes that control watermelon fruit quality. Among the genes identified are a few genes that involved in carotenoid production in watermelon. The results in this study are useful for gene discovery and for further improvement of watermelon cultivars with increase nutritional values.
Technical Abstract: A normalized cDNA library was constructed using mRNA from three distinct developmental stages of watermelon [C. lanatus (Thunb.) Matsum. & Nakai] fruit, and was subtracted by hybridization with leaf cDNA. Randomly selected cDNA clones of the watermelon fruit subtraction library were sequenced in order to identify potentially informative genes associated with fruit setting, development and ripening. Out of 1,046 sequenced cDNA clones 832 were unique sequences and designated as expressed sequenced tags (ESTs). Of these 832 ESTs, 205 (24.6%) have not been reported in any other species, 186 ESTs (22.4%) correspond to genes with unknown function, and 441 ESTs (53.0%) correspond to genes with known function in other plant species. These ESTs are mainly associated with metabolism, membrane transport, cytoskeleton synthesis and structure, cell wall formation and cell division, signal transduction, nucleic acid binding and transcription factors, defense and stress response and secondary metabolism. This study provides useful and unique information with respect to fruit-related genes in watermelon.