Organic compounds -- part of the class 532-570 series – Organic compounds – Carbohydrates or derivatives
Reexamination Certificate
2001-10-12
2004-04-20
Fox, David T. (Department: 1638)
Organic compounds -- part of the class 532-570 series
Organic compounds
Carbohydrates or derivatives
C536S023200, C536S023100
Reexamination Certificate
active
06723839
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to the field of compositions and methods for inhibiting the enzyme 1-aminocyclopropane-1-carboxylate (ACC) synthase in geranium thereby prolonging the shelf-life of cut flowers as well as reducing leaf yellowing and petal abscission during shipping and storage. Specifically, identification of the PHSacc-25 gene of geranium which may be used individually or in combination with previously identified ACC synthase genes for genetic modification of geranium.
A variety of factors cause wilting and natural abscission in flowers, particularly after a cutting of the plant or when flowers have been removed from the plant. Such factors include increased oxygen levels, wounding, chemical stress, and the plant's own production of ethylene. Of these factors, the plant's production of ethylene, has been shown to play a key role in natural senescence, the degenerative process which generally leads to controlled cell death in plants, but also in the degradation of flowers after they have been cut.
Ethylene, in all higher plants, is important to plant growth and development with respect to seed germination, seedling growth, flowering, and senescence (Abeles, F. B. et al. (1992), In:
Ethylene in Plant Biology,
Academic Press, New York, pp. 285-291; Morgan, M. E. Saltveit, J.R., “Introduction and Historical Perspectives”, Ethylene In Plant Biology, (1991), pp.1-13; Yang, S. F., et al., “Ethylene Biosynthesis and its Regulation in Higher Plants”, Plant Physiology Annual Review (1984), pp. 155-189). Ethylene production in plants can also be associated with trauma induced by mechanical wounding, chemicals, stress (such as produced by temperature and water amount variations), and by disease. Hormones can also stimulate ethylene production. Such ethylene, also sometimes called “stress ethylene”, can be an important factor in storage effectiveness for plants. Moreover, exposure of plant tissue to a small amount of ethylene often may be associated with increased production of ethylene by other adjacent plants. This autocatalytic effect may be often associated with losses in marketability of plant material during storage and transportation (Abeles et al., supra; Yang et al., supra).
The ethylene biosynthetic pathway in plants was established by Adams and Yang (Adams, D. O., et al., “Ethylene biosynthesis: Identification of 1-aminocyclopropane-1-carboxylic acid as an intermediate in the conversion of methionine to ethylene”, Proc. Nat'l Acad Sci USA 76: 170-174). The first step involves the formation of S-adenosyl-L-methionine (AdoMet) from methionine by S-adenosyl-L-methionine synthetase. AdoMet is then converted to 1-aminocyclopropane-1-carboxylate (ACC), the direct precursor of ethylene in higher plants. This conversion is catalyzed by ACC synthase (S-adenosyl-L-methionine methyl thioadenosine-lyase, EC4.4.1.14), the rate limiting step in the ethylene biosynthetic pathway. (See also Kionka, C., et al., “The enzymatic Malonylation of 1-aminocyclopropane-1-carboxylic Acid in Homogenates of Mung Bean Hypocotyls”, Planta 162: 226-235, (1984); Amrhein, N., et al., “Identification of a Major Metabolite of the Ethylene Precursor 1-Aminocyclopropane-1-carboxylic Acid in Higher Plants.”, Naturwissenschaften 68: 619-620 (1981); Hoffman, N. E., et al., “Identification of a 1-(malonylamino)cyclopropane 1-carboxylic acid as a major conjugate of 1-aminocyclopropane-1-carboxylic acid, an ethylene precursor in Higher Plants”, (1982), Biochem. Biophys. Res. Common. vol. 104, no. 2, pp.765-770.
Knowledge of the biosynthetic pathway for ethylene formation has been fundamental in developing strategies for inhibiting ethylene production in plants. One approach has been to use chemical inhibitors to inhibit the synthesis or activity of ethylene, two of the most common being aminoethoxyvinylglycine and aminooxyacetic acid (Rand, R. R., “Chemistry and Enzymology of K
Cat
Inhibitors” (1974), Science 185, pp. 320-324) and in Ethylene in Plant Biology, (Abeles, F. B., et. al., Ethylene in Plant Biology., (1992), pp. 285-291). However, chemical methods find limited use because such methods are expensive and the beneficial effect they provide is generally only short-lived.
A second approach has been to over express ACC deaminase, an enzyme which metabolizes ACC, thereby eliminating an intermediate in the biosynthesis of ethylene (Klee, et al., “Control of Ethylene Synthesis by Expression of a bacterial enzyme in Trangenic Tomato plants.”, (1991), Plant Cell 3: 1187-1193) (See also Theologis, A., et al., “Modifying Fruit Ripening By Supressing Gene Expression”, Cellular and Molecular Aspects of the Plant Hormone Ethylene, (1993), pp. 19-23). Because ACC deaminase is a bacterial enzyme, it is heterologous, and thus, external to the plant. Thus, it is unlikely that this approach will yield a modification that will be stable from generation to generation.
Yet another approach involves attempts to genetically inhibit the production of the enzymes involved in the biosynthesis of ethylene or to inhibit the biosynthesis of the enzymes directly. This approach has the advantage of not only altering the way the plant itself functions irrespective of external factors but also of presenting a system which reproduces itself, that is, the altered plant's progeny will have the same altered properties for generations to come.
Initial efforts to better understand the enzymes which catalyze the reactions in the biosynthesis of ethylene have involved the identification and characterization of the genes encoding for AdoMet synthetase, ACC synthase, and ACC oxidase (See also Kende, H. et al., “Ethylene Biosynthesis: Annual Review of Plant Physiology”, Plant Molecular Biology, (1993), pp. 283-307). Some of the genes encoding for ACC synthase have been identified for a number of plants. For instance, ACC synthase sequences have been identified for zucchini (Sato, et al., “Cloning the mRNA encoding 1-aminocyclopropane-1-carboxylate synthase, the key enzyme for ethylene biosynthesis in plants”, Proceedings of the National Academy of Sciences, (1989), pp. 6621-6625), winter squash (Nakajima, N., et al., “Molecular Cloning and Sequence of a Complementary DNA Encoding 1-Aminocyclopropane-1-carboxylate Synthase Induced by Tissue Wounding”, Plant Cell Physiology, (1990), pp. 1021-1029), tomato (Van Der Straeten, D., et al., “Cloning and Sequence of two different cDNAs encoding 1-aminocyclopropane-1-carboxylate Synthase in a Tomato”, Proceedings of the National Academy of Sciences, (1990), pp. 4859-4863); (Rottmann, W. H., et al., “Theologis: A 1-Aminocyclopropane-i-Carboxylate Synthase in Tomato Is Encoded by a Multigene Family Whose Transcription Is Induced During Fruit and Floral Senescence”, Journal of Molecular Biology, (1991), pp. 937-961), apple (Dong, J. G., et al., “Cloning of a cDNA Encoding 1-aminocyclopropane-1-carboxylate Synthase and Expression of its mRNA in Ripening Apple Fruit”, Planta, pp. 38-45 (1991)), mung bean (Botella, J. R, et al., “Identification and Characterization of a Full-length cDNA Encoding for an Auxin-induced 1-aminocyclopropane-1-carboxylate Synthase from Etiolated Mung Bean Hypocotyl Segments and Expression of its mRNA in Reponse to Indole-3-acetic Acid”, Plant Molecular Biol 20, pp. 425-436 (1992); Botella, J. R., et al., “Identification and characterization of three putative genes for 1-Aminocyclopropane-1-carboxylate Synthase from etiolated mung bean hypocotyl segments”, Plant Mol Biol 18, pp. 793-797 (1992); Botella, J. R., et al., “Identification of two new members of the 1-Aminocyclopropane-1-carboxylate Synthase-Encoding Multigene family in mung bean”,
Gene
06852, pp. 249-253, (1993)); Kim W., et al., “Induction of 1-aminocyclopropane-1-carboxylate Synthase mRNA by Auxin in Mung Bean Hypocotyls and Cultured Apple Shoots”, (1991), Plant Physiol 98:465-471), carnation (Park, K. Y., et al., “Molecular cloning of an 1-aminocyclopropane-1-carboxylate synthase from senescing carnation flower petals”, Plant Molecular Biology, (1992), Vol. 18, pp. 377-
Colorado State University through its agent Colorado State Unive
Fox David T.
Kallis Russell
Santangelo Law Offices P.C.
LandOfFree
Partial gene sequence from pelargonium to control ethylene... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Partial gene sequence from pelargonium to control ethylene..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Partial gene sequence from pelargonium to control ethylene... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3200467