Abstract: A full-length transcript promoter from mirabilis mosaic caulimovirus (MMV) is identified and its DNA sequence given. The promoter functions as a strong and uniform promoter for chimeric genes inserted into plant cells. This strong promoter function is exhibited by histochemical assay in seeds and floral organs and by reproductive scores of transgenic plants including the promoter. The promoter preferably includes a 3′ untranslated region that may be from the MMV itself or from a heterologous source with respect to the promoter. The promoter is used in a chimeric gene and in methods for transforming plant cells to obtain transgenic plants, plant tissues, plant cells and seeds incorporating the MMV promoter. The MMV FLT promoter shows greater activity (14 to 24 fold) than the CaMV 35S promoter. A modified MMV FLt promoter with duplicated enhancer domains shows greater activity (3 fold) than with a single enhancer domain.

Abstract: Use of wild type and modified viral FLt promoters of FMV in the expression of chimeric genes in plant cells. The FLt promoter from FMV is modified with duplicated enhancer domains. The FLt promoter with its single or double enhancer domains is linked to heterologous coding sequences to form chimeric gene constructs. These genes have been shown to be expressed well in plant cells.