Patent EA-003423-B1 (EA)
Title: A culture of transgenic plant cells and transgenic plant, comprising expression cassette of usp receptor target polypeptide, methods of producing of their progeny, methods for controlling of expression of target polypeptide in said plant by juvenile hormone and one of its antagonists, methods of detecting and producing of ligand for usp receptor polypeptide and the corresponding ligand
Inventor: CROSSLAND LYLE DEAN
IPC: C07K14/705
Filed: 1996-09-27
Abstract: 1. A culture of transgenic plant cell, comprising: a) a USP receptor expression cassette, which encodes a USP receptor polypeptide for controlling expression of the target polypeptide and; b) a target expression cassette encoding a target polypeptide, comprising a target polypeptide gene, the expression of which is mediated by USP receptor on juvenile hormone or one of its agonists, and optionally c) a secondary receptor expression cassette encoding a secondary receptor polypeptide distinct from the USP receptor polypeptide for controlling expression of the target polypeptide. 2. A culture of plant cells, according to claim 1, wherein expression of the target expression cassette interferes with plant fertility. 3. A transgenic plant, comprising: a) a USP receptor expression cassette, which encodes a USP receptor polypeptide for controlling expression of the target polypeptide and; b) a target expression cassette encoding a target polypeptide, comprising a target polypeptide gene, the expression of which is mediated by USP receptor on juvenile hormone or one of its agonists, and optionally c) a secondary receptor expression cassette encoding a secondary receptor polypeptide distinct from the USP receptor polypeptide for controlling expression of the target polypeptide. 4. The plant according to claim 3 comprising expression of the target expression cassette interferes with plant fertility. 5. The plant according to claim 3 wherein said plant is maize. 6. The plant according to claim 3 wherein said plant is wheat. 7. A method of preparing of daughter culture of transgenic plant cell, comprising a transformation of plant cell by means of: a) a USP receptor expression cassette, which encodes a USP receptor polypeptide for controlling expression of the target polypeptide and; b) a target expression cassette encoding a target polypeptide, comprising a target polypeptide gene, the expression of which is mediated by USP receptor on juvenile hormone or one of its agonists, and optionally c) a secondary receptor expression cassette encoding a secondary receptor polypeptide distinct from the USP receptor polypeptide for controlling expression of the target polypeptide, and d) a selection of transformed cells and growing of these cells with the obtaining of daughter culture. 8. A method of preparing of progeny of transgenic plant according to claim 3, comprising plant cells transformation by means of: a) a USP receptor expression cassette, which encodes a USP receptor polypeptide for controlling expression of the target polypeptide and; b) a target expression cassette encoding a target polypeptide, comprising a target polypeptide gene, the expression of which is mediated by USP receptor on juvenile hormone or one of its agonists, and optionally c) a secondary receptor expression cassette encoding a secondary receptor polypeptide distinct from the USP receptor polypeptide for controlling expression of the target polypeptide, and d) regeneration of said cells to transgenic plant and, e) a selection of transformed plants, insemination by self-fertilization, obtaining of seed and growing them. 9. A method of regulation of expression of the target polypeptide in plant according to claim 3, comprising: a) providing the expression of USP receptor polypeptide and target polypeptide in plant and optionally secondary receptor polypeptide due to transformation of the plant cell by correspondent cassettes and b) contacting plant cells with juvenile hormone or one of its agonists 10. The method according to claim 9 wherein expression of the target polypeptide is increased or activated in the presence of juvenile hormone or one of its agonists. 11. The method according to claim 9 wherein expression of the target polypeptide is decreased or inhibited in the presence of juvenile hormone or one of its agonists. 12. The method according to claim 9 wherein the USP receptor polypeptide comprises a heterologous transactivation domain. 13. The method according to claim 12 wherein said heterologous transactivation domain is the transactivation domain from the VP16 protein of herpes simplex. 14. The method according to claim 9 wherein said secondary receptor polypeptide is selected from the group consisting of EcR, DHR38 and RXR. 15. The method according to claim 9 wherein said agonist is selected from the group consisting of fenoxycarb, diofenolan, kinoprene, methoprene, hyrdoprene, diofenolan, methoprene acid, triflumuron, hexamflumuron, teflubenzuron, flufenoxuron, flucycloxuron, and lufenuron, diflubenzuron and chlorfluzuron. 16. The method according to claim 7 wherein said target expression cassette comprises a 5' regulatory region comprising between 1 and 11 copies of a response element. 17. A method of controlling the fertility of a plant according to claim 4, comprising: a) providing the expression of USP receptor polypeptide and target polypeptide in plant and optionally secondary receptor polypeptide due to transformation of the plant cell by correspondent cassettes and b) contacting said plant with juvenile hormone or one of its agonists. 18. The method according to claim 17 wherein expression of the target polypeptide is increased or activated in the presence of juvenile hormone or one of its agonists. 19. The method according to claim 17 wherein expression of the target polypeptide is decreased or inhibited in the presence of juvenile hormone or one of its agonists. 20. The method according to claim 17 wherein the USP or the secondary receptor expression cassette comprises an anther-specific promoter operably linked to the coding sequence for the receptor polypeptide. 21. The method according to claim 17 wherein the USP or the secondary receptor expression cassette comprises a pistil-specific promoter operably linked to the coding sequence for the receptor polypeptide. 22. The method according to claim 17 wherein the target polypeptide is the ribonuclease barnase. 23. The method according to claim 17 wherein the target expression cassette encodes an anti-sense sequence rendering fertilization ineffective. 24. The method according to claim 17 wherein the target polypeptide restores effective fertilization. 25. The method according to claims 24 wherein the target polypeptide is the ribonuclease inhibitor barstar. 26. A method of identifying a ligand of a USP receptor polypeptide which in a plant cell environment according to claim 1, activates or inhibits expression of a target expression cassette comprising the steps of: a) expression of USP receptor polypeptide and target polypeptide in plant and optionally secondary receptor polypeptide due to transformation of the plant cell by correspondent cassettes and b) contacting said plant with juvenile hormone or one of its agonists. c) determining expression of the target polypeptide; and d) identifying test substances which significantly activate or inhibit expression of the target polypeptide. 27. The method according to claim 26 wherein the expression of the target polypeptide is determined qualitatively. 28. The method according to claim 26 wherein the expression of the target polypeptide is determined quantitatively. 29. A method of producing a ligand of a USP receptor polypeptide comprising the steps of: a) synthesizing novel test substances in accordance with processes known in the art; b) culturing progeny cells of said transformed daughter plant cells; c) expression of USP receptor polypeptide and optionally secondary receptor polypeptide in culture of daughter plant cells. d) contacting a culture of daughter plant cells with a test substance of step a); and e) determining expression of the target polypeptide; f) selecting a test substance which significantly activates or inhibits expression of the target polypeptide; and g) repeating process step a) for the substance selected in process step f). 30. A ligand of a USP receptor obtainable by a process according to claim 29. 31. Use of juvenile hormone or a juvenile hormone agonist to control expression of a target polypeptide in a culture cells according to claim 1 or a plant according to claim 3.