Abstract: The present invention provides novel DNA constructs and methods for stably transforming the plastids of higher plants. The constructs described herein contain unique promoters that are transcribed by both nuclear encoded plastid polymerases and plastid encoded plastid polymerases. Use of the novel constructs of the invention facilitates transformation of a wider range of plant species and enables tissue specific expression of a transforming DNA in plastids of multicellular plants.

Abstract: DNA constructs are provided for stable transformation of plastids of multicellular plants and expression of foreign proteins in plastids. The DNA constructs comprise a transforming DNA which is targeted to a pre-determined location on the plastid genome and inserted into the plastid genome by homologous recombination with targeting segments comprising DNA sequences homologous to the pre-determined region of the plastid genome. The transforming DNA contains a non-lethal selectable marker gene which confers a selectable phenotype on cells having plastids in which substantially all of the genomes therein contain the transforming DNA (i.e., homoplasmic cells or tissues). The transforming DNA further comprises at least one insertion site 4 for an additional DNA segment, such as a gene encoding a protein for improving a characteristic of the transformed plant.