Use of the malonyl transferase gene

SUMMARY An object of the present invention is to provide a method of producing a flavone in which a malonyl group is added to a glucose at position 7 using a polynucleotide encoding a protein that has activity that transfers a malonyl group to position 6 of glucose at position 7 of the flavone 7-glucoside， and creates a plant variety that has a modified flower color， and preferably a flower color that is bluer than that of existing varieties， as it contains as a pigment a flavone in which a malonyl group has been added to glucose at position 7. A polynucleotide is used which is selected from the group consisting of， for example: (a) a polynucleotide composed of the base sequence of SEQ ID NO: 1; (b) a polynucleotide that hybridizes under stringent conditions to a polynucleotide consisting of the base sequence complementary to the base sequence of SEQ ID NO: 1 and encodes a protein that has activity that transfers a malonyl group to position 6 of glucose at position 7 of flavone 7-glucoside; (c) a polynucleotide encoding a protein consisting of the amino acid sequence of SEQ ID NO: 2; and， (d) a polynucleotide encoding a protein consisting of an amino acid sequence in which one or a few amino acids have been removed， replaced， inserted and / or added in the amino acid sequence of SEQ ID NO: 2 and has activity that transfers a malonyl group to position 6 of glucose at position 7 of flavone 7-glucoside.

发明概述 本发明的目的在于提供一种黄酮类化合物的制备方法，该方法采用编码具有将丙二酰基 (malonyl group) 转移至黄酮7-葡萄糖苷 (flavone 7-glucoside) 中7位连接的葡萄糖的6位的活性的蛋白质的多核苷酸 (polynucleotide)；同时培育得到花色经修饰的植物品种，优选花色较现有品种更偏蓝的品种，因该类植物以7位葡萄糖连有丙二酰基的黄酮类化合物作为色素。所使用的多核苷酸选自以下组：(a) 由序列表序列号1（SEQ ID NO:1）的碱基序列构成的多核苷酸；(b) 在严谨条件 (stringent conditions) 下与SEQ ID NO:1的碱基序列互补的多核苷酸杂交，且编码具有将丙二酰基转移至黄酮7-葡萄糖苷中7位连接的葡萄糖的6位的活性的蛋白质的多核苷酸；(c) 编码由SEQ ID NO:2的氨基酸序列构成的蛋白质的多核苷酸；(d) 编码在SEQ ID NO:2的氨基酸序列中缺失、替换、插入和/或添加一个或数个氨基酸所得的氨基酸序列构成的蛋白质，且该蛋白质具有将丙二酰基转移至黄酮7-葡萄糖苷中7位连接的葡萄糖的6位的活性的多核苷酸。