Jasmonateinduced Alteration of Gene Expression

In all plants studied so far, treatment with jasmonates exerts two different changes in gene expression: (i) decrease in the expression of nuclear- and chloroplast-encoded genes mainly involved in photosynthesis (Reinbothe et al., 1997), (ii) increase in the expression of specific genes. Decreased gene expression caused by jasmonates has been shown to be (i) transcriptionally regulated in the case of the small and large subunits of Rubisco and chlorophyll a/b binding protein (Reinbothe et al., 1997; Wierstra and Kloppstech, 2000) and (ii) translationally regulated in the case of some plastid-located proteins (Reinbothe et al., 1993). Both types of regulation may contribute to the senescence-promoting effect of jasmonates (see Section VI).

The genes up regulated by jasmonates code for proteins of various functions (Table 9-1).

Some of these proteins were found to be encoded by SAGs indicating the overlap in plant defense response and senescence (Fig. 9-3) (cf. Sections V, VI).

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