Plant & Animal Genomes XIV Conference

January 14-18, 2006
Town & Country Convention Center
San Diego, CA

Global Analysis Of Gene Expression During Development And Ripening Of Citrus Fruit Flesh

Manuel Cercos , Guillermo Soler , Manuel Talon

  Instituto Valenciano de Investigaciones Agrarias. Centro de Genómica. Ctra. Moncada-Náquera Km 4.6, 46113 Moncada, Valencia, Spain

Microarrays of cDNA have been used to examine expression changes of 7000 genes during development and ripening of the fruit flesh of self-incompatible Citrus clementina, a non-climateric species. The data indicated that 2243 putative unigenes showed significant expression changes. Functional classification revealed that genes encoding for regulatory proteins were significantly overrepresented in the up-regulated gene clusters. The most abundant sets of induced transcription factors were the NAC, MADS and MYB families. Enrichment in the functional category of genes interacting with environment was predominant in the down-regulated gene clusters. The analyses also highlighted key physiological processes occurring during citrus fruit development and ripening such as cell expansion, water accumulation, sucrose build-up, acid reduction, pigment substitutions (carotenoid accumulation and anthocyanin and flavonoid decreases), ascorbic acid diminution and lipid decline. Often, results strongly suggested prevalence of specific metabolic alternatives.