Abstract: The present invention is directed to the genetic transformation using multiple genetic sequences, wherein one of said genetic sequences encodes a polypeptide possessing excision activity, specifically a site-specific recombinase activity linked to a transgene unit and the use of this genetic construct in the removal of transgenes therefrom. The present invention provides the means to produce genetically-transformed organisms, in particular plants, in which selectable marker genes have been removed, thereby facilitating multiple sequential genetic transformation events using the same selectable marker gene. Accordingly, the invention provides the means for regulating transgene expression in genetically-manipulated organisms, for example to promote differentiation, de-differentiation, or any unidirectional developmental shift of a target cell which requires the time-specific expression of a particular gene.

Abstract: The present invention is directed to transcription regulators and transcription regulator-like sequences of nanovirus origin. As used in the specification, the nanovirus group is consdiered to include subterranean clover stunt virus (SCSV), cocnut foliar decay virus (CFDV), banana bunchy top virus (BBTV), milk vetch dwarf cirus (MDV), and faba bean necrotic yellow virus (FBNYV). The transcription regulators and transcription regulator-like sequences of the instant invention are useful in genetic engineering of plants and in particular leguminous plants such as to facilitate or control expression of foreign genes. The transcription regulators and transcription regulator-like sequences of the present invention are also useful in facilitating different levels of expression in different plant tissue types.