Abstract: The invention relates to a chemically-inducible plant gene expression cassette and to plant cells transformed therewith. The expression cassette is suitable for use in any dicotyledonous or monocotyledonous plant. It comprises a first promoter operatively linked to a regulator sequence which encodes a regulator protein, and an inducible promoter operatively linked to a target gene, the inducible promoter being activated by the regulator protein in the presence of an effective exogenous inducer whereby application of the inducer causes expression of the target gene. The regulator sequence may be derived from the alcR gene, and the inducible promoter may be derived from the alcA gene promoter (both obtainable from Aspergillus nidulans). A chimeric promoter comprising an upstream regulatory region and a heterologous downstream transcription initiation region is also disclosed. The regulatory sequence may be derived from the alcA gene promoter.

Abstract: Process for the inhibition of the production of a gene product in a plant cell which comprises generating in the cell while the gene product is being expressed mRNA from recombinant DNA coding for part only of the gene product: also constructs for use in the process, and cells and plants that carry out the process. Specifically applicable to control of fruit ripening, in particular in tomatoes.

Abstract: The chemically-inducible 27 kD subunit of the enzyme glutathione-S-transferase, isoform II (GST-II-27) and sequences encoding it are provided. In particular, a genomic DNA sequence encoding the gene promoter for the GST-II-27 subunit is provided. When linked to an exogenous gene and introduced into a plant by transformation, the GST-II-27 promoter provides a means for the external regulation of expression of that exogenous gene. Transformation with DNA encoding glutathione-S-transferase polypeptides produces herbicide resistance transgenic plants.

Abstract: Three similar gene sequences are provided, the sequences being shown in the drawings, which are recovered from male flower parts of maize, specifically anther tissue. When one or more of these sequences are included in a gene construct, expression of an encoded protein is restricted to male parts of the plant. The sequences have utility in any application where expression in male flower parts is indicated, a specific application is in the control of expression of a disrupter protein which imparts male sterility when incorporated in a plant genome.

Abstract: A method is provided for making fruit (particularly tomatoes) having increased solids content which comprises cultivating fruit-bearing plants in which expression of genes homologous to pTOM36 is at least partially inhibited. For this purpose the fruit may be transformed with DNA constructs comprising a DNA sequence homologous to some or all of the gene encoded by the clone pTOM36. The clone is adapted to generate sense or antisense RNA under control of a plant promoter.

Abstract: DNA clones, e.g. M13-1, comprising at least part of a gene derived from melon that encodes ethylene-forming enzyme. Such clones may comprise DNA constructs including plant promoters capable of expressing RNA in plant cells. Such constructs may be used to inhibit production of ethylene-forming enzyme in transformed plants, and thereby to produce slower-ripening fruit, particularly melons. The clones may be obtained by PCR using specific oligo-nucleotide primers.

Abstract: Recombinant DNA comprises promoter and terminator base sequences respectively upstream and downstream of an inverted base sequence complementary to a substantial sequence of bases in polygalacturonase mRNA. The antisense mRNA produced thereby delays softening of fruit, in particular tomatoes.

Abstract: The synthesis of lignin by plants is controlled by transformation of the plant genome with a recombinant gene construct which contains the gene specifying an enzyme critical to the synthesis of a lignin precursor, which gene may be in antisense orientation so that it is transcribed to mRNA having a sequence complementary to the equivalent mRNA transcribed from the endogenous gene thus leading to suppression of lignin synthesis. If the recombinant gene has the lignin enzyme gene in normal, or "sense" orientation, increased production of the enzyme may occur when the insert is the full length DNA but suppression may occur if only a partial sequence is employed.

Abstract: DNA clones, e.g. P13-B, comprising at least part of a gene derived from peach that encodes ethylene-forming enzyme. Such clones may comprise DNA constructs including plant promoters capable of expressing RNA in plant cells. Such constructs may be used to inhibit production of ethylene-forming enzyme in transformed plants, and thereby to produce slower-ripening fruit, particularly peaches. The clones may be obtained by PCR using specific oligo-nucleotide primers.

Abstract: DNA construct for use in transforming plant cells comprises and exogenous gene with upstream promoter and downstream terminator sequences, the promoter being a DNA sequence of not less than about 5 kilobases homologous to the DNA control sequence found upstream of the tomato PG gene. Preferably the terminator is homologous to the DNA control sequence of about 1.6 kilobases found downstream of the tomato polygalacturonase gene. Enhanced expression of the exogenous gene is obtained. The invention also included plant cells containing such constructs and plants derived therefrom.

Abstract: Fruit, especially tomatoes, having lowered expression of fruit-softening enzymes caused by antisense gene expression, and seeds therefrom.

Abstract: DNA constructs useful for modifying the ripening behavior of fruit comprise a transcriptional initiation region operative in plants positioned for transcription of a DNA sequence homologous to some or all of a fruit-ripening gene encoded by either of the clones pTOM136 or pTOM66, so that the construct can generate RNA in plant cells. Also plant cells and plants transformed with such constructs.

Abstract: The gene of the construct pTOM5 is involved in the carotenoid pathway, which produces carotenes, lutein, xanthophylls, and pigments such as lycopene. The invention proposes to modify (inhibit or promote) the synthesis of such compounds in plants using novel DNA constructs comprising a DNA sequence homologous to some or all of the gene encoded by the clone pTOM5, preceded by a plant promoter. In particular, colour of plant parts, especially fruit, may be modified. Yellow tomatoes are disclosed.

Abstract: Process for the inhibition of the production of a gene product in a plant cell which comprises generating in the cell while the gene product is being expressed mRNA from recombinant DNA coding for part only of the gene product: also constructs for use in the process, and cells and plants that carry out the process. Specifically applicable to control of fruit ripening, in particular in tomatoes.

Abstract: DNA constructs comprise a DNA sequence homologous to some or all of the gene encoded by the clone pTOM36. The constructs may further comprise a transcriptional initiation region operative in plants for transcribing this DNA sequence, optionally in the antisense direction to produce mRNA complementary to the pTOM36 gene. Transformed plant cells and plants may be derived from such constructs: fruit from the plants (such as tomatoes) are expected to have modified ripening properties.

Abstract: Recombinant DNA comprises promoter and terminator base sequences respectively upstream and downstream of an inverted base sequence complementary to a substantial sequence of bases in polygalacturonase mRNA. The antisense mRNA produced thereby delays softening of fruit, in particular tomatoes.