Location: Plant, Soil and Nutrition ResearchTitle: Expression of ripening-related genes in cold stored tomato fruit) Author
Submitted to: Postharvest Biology and Technology
Publication Type: Peer reviewed journal
Publication Acceptance Date: 2/25/2011
Publication Date: 6/27/2011
Citation: Rugkong, A., Mcquinn, R., Giovannoni, J.J., Rose, J., Watkins, C. 2011. Expression of ripening-related genes in cold stored tomato fruit. Postharvest Biology and Technology. 61:1-14. Interpretive Summary: Horticultural crops that originated in tropical and subtropical origin are especially susceptible to chilling injury (CI) caused by exposure to low, but higher than freezing point, temperatures. Susceptibility of fruits and vegetables to CI is an important postharvest problem because the extent to which low temperature storage can be used to control ripening and deterioration for storage and transport is limited: 13 -15 degrees C is typically an optimum storage temperature for many CI-sensitive crops. While the effect of chilling on fruit ripening has been reported in many studies, few have examined the effects of chilling on the expression of ripening-related genes at a whole transcriptome level. We examined whole genome transcriptome response to chilling using microarray expression tools and have identified candidate genes that may be related to both chilling injury and responses to protect fruit tissues from chilling damage.
Technical Abstract: The effects of chilling on fruit ripening and the expression of ripening-related genes have been investigated in a wild species introgression breeding tomato line (Solanum lycopersicum ' S. pennelli) that preliminary investigations suggested harbors some fruit chilling tolerance. Fruit were harvested at the breaker stage of ripening were, stored at 3 degrees C for 0, 1, 2 and 4 weeks, followed by 20 degrees C for 0 to 14 d. Fruit stored for 1 week ripened normally as assessed by red color development and softening at 20 degrees C, but those stored for 2 and 4 weeks showed delayed or inhibited ripening. The concentrations of the carotenoids, phytoene, phytofluene, z-carotene, g-carotene and lycopene, but not lutein and beta-carotene, were reduced in chilled fruit. Microarray analysis showed that after storage at 3 degrees C for 4 weeks, 352 genes were up-regulated by chilling, whereas 321 genes were down-regulated, while after 7 d at 20 degrees C, 180 and 126 genes, respectively, were up- and down-regulated in chilled fruit. Chilling-induced changes included expression of transcriptional repressors such as a C2H2-type zinc finger protein and chilling reduced gene expression of a ripening-regulated transcription factor, LeMADS-RIN.