US 5,723,765 A · Control of plant gene expression

Abstract

A method for making a genetically modified plant comprising regenerating a whole plant from a plant cell that has been transfected with DNA sequences comprising a first gene whose expression results in an altered plant phenotype linked to a transiently active promoter, the gene and promoter being separated by a blocking sequence flanked on either side by specific excision sequences, a second gene that encodes a recombinase specific for the specific excision sequences linked to a repressible promoter, and a third gene that encodes the repressor specific for the repressible promoter. Also a method for making a genetically modified hybrid plant by hybridizing a first plant regenerated from a plant cell that has been transfected with DNA sequences comprising a first gene whose expression results in an altered plant phenotype linked to a transiently active promoter, the gene and promoter being separated by a blocking sequence flanked on either side by specific excision sequences to a second plant regenerated from a second plant cell that has been transfected with DNA sequences comprising a second gene that encodes a recombinase specific for the specific excision sequences linked to a promoter that is active during seed germination, and growing a hybrid plant from the hybrid seed. Plant cells, plant tissues, plant seed and whole plants containing the above DNA sequences are also claimed.

Claims55

Dependent claims

A method for making a genetically modified plant comprising

stably transforming a plant cell with a first DNA sequence comprising a first gene whose expression results in an altered plant phenotype, and a transiently-active promotor, the first gene and the transiently-active promotor being operably linked to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the first gene, a second DNA sequence comprising a second gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor operably linked in functional relation to the second gene, and a third DNA sequence comprising a third gene that encodes a repressor specific for the repressible promotor of the second DNA sequence, the third sequence being linked to a plant-active promoter;
regenerating a whole plant from the plant cell.

A method for producing seed that is incapable of germination, comprising

stably transforming a plant cell with a first DNA sequence comprising a lethal gene and a promotor that is active in late embryogenesis, the lethal gene and the late embryogenesis promotor being in functional relation to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the lethal gene, a second DNA sequence comprising a gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor linked in functional relation to the specific recombinase gene, and a third DNA sequence comprising a gene that encodes a repressor specific for the repressible promotor of the second DNA sequence, third sequence being linked to a plant-active promoter;
regenerating a whole plant from the plant cell;
allowing the regenerated whole plant to produce a first generation seed;
exposing the first generation seed to a stimulus that blocks the function of the repressor, such that the repressor element no longer inhibits expression of the specific recombinase gene, thereby allowing expression of the specific recombinase and excision of the blocking sequence of the first DNA sequence at the specific excision sequences, resulting in the direct functional linkage of the late embryogenesis promotor with the lethal gene;
germinating the first generation seed to produce a first generation plant expressing the late embryogenesis promotor/lethal gene sequence;
allowing the plant to produce second generation seed, whereby in the course of embryogenesis, the late embryogenesis promotor becomes active, permitting expression of the lethal gene in the second generation seed, thereby rendering the second generation seed incapable of germination.

3 more elements

A transgenic plant stably transformed with DNA sequences comprising

a first DNA sequence comprising a first gene whose expression results in an altered plant phenotype, and a transiently active promotor, the first gene and the transiently active promotor being in functional relation to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the first gene,
a second DNA sequence comprising a second gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor linked in functional relation to the second gene, and
a third DNA sequence comprising a third gene that encodes a repressor element specific for the repressible promotor of the second DNA sequence, the third sequence being linked to a plant-active promoter.

Plant seed that has been stably transformed with exogenous DNA comprising

a first DNA sequence comprising a first gene whose expression results in an altered plant phenotype, and a transiently active promotor, the first gene and the transiently active promotor being in functional relation to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the first gene,
a second DNA sequence comprising a second gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor linked in functional relation to the second gene, and
a third DNA sequence comprising a third gene that encodes a repressor element specific for the repressible promotor of the second DNA sequence, the third sequence being linked to a plant-active promoter.

Plant tissue that has been stably transformed with exogenous DNA comprising

a first DNA sequence comprising a first gene whose expression results in an altered plant phenotype, and a transiently active promotor, the first gene and the transiently active promotor being in functional relation to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the first gene,
a second DNA sequence comprising a second gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor linked in functional relation to the second gene, and
a third DNA sequence comprising a third gene that encodes a repressor element specific for the repressible promotor of the second DNA sequence, the third sequence being linked to a plant-active promoter.

A plant cell that has been stably transformed with exogenous DNA comprising

a first DNA sequence comprising a first gene whose expression results in an altered plant phenotype, and a transiently active promotor, the first gene and the transiently active promotor being in functional relation to one another, but separated by a blocking sequence that is flanked by specific excision sequences, such that the presence of the blocking sequence prevents the expression of the first gene,
a second DNA sequence comprising a second gene that encodes a recombinase specific for the specific excision sequences flanking the blocking sequence of the first DNA sequence, and a repressible promotor linked in functional relation to the second gene, and
a third DNA sequence comprising a third gene that encodes a repressor element specific for the repressible promotor of the second DNA sequence, the third sequence being linked to a plant-active promoter.

Dependencies are inferred from the claim text.

Control of plant gene expression

Life of this patent

Control of plant gene expression

Life of this patent

Abstract

Claims55