Gene expression in ripening tomato fruit

Ripening involves alterations in physical and chemical composition which enhance the attractiveness of a fruit to a potential consumer. The process depends upon changes in physiology and biochemistry in several cell compartments including the nucleus, chloroplast, nitochondrion and cell wall. Separate aspects of ripening, which normally occur in a coordinate fashion, can be distinguished by physiological experiments and by studying mutants. These include biosynthetic as well as degradative events. Biochemical and genetic evidence indicates that the expression of specific genes is of critical importance in normal ripening. Studies on the identification and function of these genes involved in the “ripening program” and attempts to elucidate the way in which their expression is controlled during ripening are discussed.