Fruit Promoters

Summary

Among the large patent portfolio of Calgene on tissue-specific promoters, there are three main patent families containing granted patents directed to fruit-specific regulatory regions. Patents and patent applications that were assigned to Calgene may now be held by Monsanto, to which any inquiries about licensing should be directed (http://www.monsanto.com/monsanto/layout/about_us/contactus.asp).

Patents of one of the patent families are drawn to DNA constructs containing promoters “preferentially expressed in fruit tissues”.  Although the basic patents in the patent family are involved in the expression of genes regulating fruit ripening and drive the expression of genes of interest in mature ovaries, the definitions are broad, and examples in which seed-specific expression is cited suggest that tissues such as seed, fruit integument, cotton fibers and so on would be construed as “fruit tissues”. In addition, general methods to regulate the fruit phenotype are part of the patented inventions.

In the other two patent families, the definitions are more specific.  One relates primarily to cotton fiber production, although it contains some broader claims. In the second, the promoters of the invention are expressed in receptacle tissue, a flower part that makes most of the fleshy tissue in accessory fruits such as strawberry, apple and pear. The genes driven by the promoter influence fruit development, maturation and ripening.  Some analysis of this patent family is provided below.

Broadest patent family

The claims of the United States patent are drawn to methods for altering the phenotype of the fruit tissue of a plant transformed with DNA constructs comprising:

• a promoter preferentially expressed in a fruit tissue (note that this does not mean “fruit-specific”);
• a DNA sequence of interest different from the native gene of the promoter (note that this need not be a “gene”–could be antisense or RNAi); and
• a transcriptional termination region.

Unlike the European patent, the genes from which the fruit-specific promoters are obtained are not limited to anthesis process or fruit maturation and ripening. The promoters are from genes preferentially transcribed in fruit tissue. Because there is no limitation in the fruit gene promoter used in the DNA construct to alter the phenotype of a fruit, the invention claimed in the United States patent, although directed to methods, is broader in scope than in the Canadian and European patents. Also, the claimed methods are described in very broad terms.

Calgene’s European patent claims:

• A DNA construct comprising a fruit transcriptional initiation region from a gene that becomes active during anthesis (period during which a flower is fully open and functional), remains active until the ripe period and is transcribed in mature ovary tissue. The construct includes a gene of interest under the control of such transcriptional region and a transcriptional termination region.
• A DNA construct having a fruit promoter of a plant storage protein that becomes and remains active during the stages described above.
• A method for the modification of the phenotype of a tomato fruit. The sort of phenotypic modification is not specified in the claim.
• A tomato cell is transformed with a DNA construct as described above. A tomato plant is regenerated and grown from the transformed cell.

Note: Patent information was last updated on 15 May 2006. Search terms: “promoter” in abstract and “Calgene” in applicant. Patent database: PatentLens in combination with INPADOC.

Cotton fiber patent family

As mentioned above, Cotton (Gossypium hirsutum) fiber can be construed as a type of “fruit tissue” in broader botanical terms. Calgene has a United States patent  directed to a promoter from cotton expansin gene. The cotton expansin gene is expressed in developing fiber and, according to the specification, the promoter of the cotton expansin gene can be used to drive a gene of interest in developing cotton fiber for modifying cotton fiber phenotypes.

Note: Patent information was last updated on 18 May 2006. Search terms: “promoter” in abstract and “Calgene” in applicant. Patent database: PatentLens in combination with INPADOC.

Receptacle patent family

A European patent application and a granted United States patent filed by Calgene are directed to fruit promoters in general driving the expression of genes in the receptacle tissue of a fruit.

Specific Patent Information

Note: Patent information was last updated on 15 May 2006. Search terms: “promoter” in abstract and “Calgene” in applicant. Patent database: PatentLens in combination with INPADOC.