title: Expression of the C4 Me1 Gene from Flaveria bidentis Requires an Interaction between 5[prime] and 3[prime] Sequences.
abstract: The efficient functioning of C4 photosynthesis requires the strict compartmentation of a suite of enzymes in either mesophyll or bundle sheath cells. To determine the mechanism controlling bundle sheath cell-specific expression of the NADP-malic enzyme, we made a set of chimeric constructs using the 5[prime] and 3[prime] regions of the Flaveria bidentis Me1 gene fused to the [beta]-glucuronidase gusA reporter gene. The pattern of GUS activity in stably transformed F. bidentis plants was analyzed by histochemical and cell separation techniques. We conclude that the 5[prime] region of Me1 determines bundle sheath specificity, whereas the 3[prime] region contains an apparent enhancer-like element that confers high-level expression in leaves. The interaction of 5[prime] and 3[prime] sequences was dependent on factors that are present in the C4 plant but not found in tobacco.
authors.affiliation: CSIRO Plant Industry, GPO Box 1600, Canberra 2601, Australia.
authors.forename: J. S.
authors.initials: JS
authors.lastname: Marshall
authors.forename: J. D.
authors.initials: JD
authors.lastname: Stubbs
authors.forename: J. A.
authors.initials: JA
authors.lastname: Chitty
authors.forename: B.
authors.initials: B
authors.lastname: Surin
authors.forename: W. C.
authors.initials: WC
authors.lastname: Taylor