We have isolated and characterized cDNA clones for the leaf-specific C4-phosphoenolpyruvate carboxylase (PEPCase) from the dicotyledonous C~ plant Flaveria trhtervia. The isolation of multiple cDNAs indicates that in this plant the C~ isoform is encoded by a small subgroup of the PEPCase gone family. The deduced amino acid sequence reveals a higher degree of similarity to the CAM and C~ isozymes of the dicotyledonous, facultative CAM plant Mesembryanthemum crystallimtm than to the Ca PEPCases of monocotyledonous origin.