Study on molecular mechanism of green cocoon of the silkworm

Research Project

Project/Area Number	25450490
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Insect science
Research Institution	National Institute of Agrobiological Sciences
Principal Investigator	Hirayama Chikara 国立研究開発法人農業生物資源研究所, 昆虫機能研究開発ユニット, 主任研究員 (90370676)
Co-Investigator(Kenkyū-buntansha)	YAMAMOTO Kimiko 国立研究開発法人農業・食品産業技術総合研究機構, 先進昆虫ゲノム改変ユニット, ユニット長 (40370689)
Co-Investigator(Renkei-kenkyūsha)	MASE Keisuke 日本大学文理学部, 物理生命システム科学科, 教授 (60414942)
Project Period (FY)	2013-04-01 – 2016-03-31
Project Status	Completed (Fiscal Year 2015)
Budget Amount *help	¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000) Fiscal Year 2015: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000) Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000) Fiscal Year 2013: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords	フラボノイド / カイコ / 繭色素 / 代謝異常 / 緑繭 / P5CR / 突然変異 / 配糖体
Outline of Final Research Achievements	We found that the cocoon color changed from yellowish-green to pale-green due to a significant reduction of prolinylflavonols, if the chromosome 6 of Daizo was replaced by that of J01. We generated a knockout silkworm strain for BmP5CR1 using transcription activator-like effector nucleases (TALEN) technology. BmP5CR1 knockout silkworms exhibited yellowish-green cocoon, with the formation of prolinylflavonols. In addition, several complexes, which were considered to be prolinylflavonols, are formed between quercetin and P5C without catalysts in vitro. These results provide the first evidence that “Ryoku-ken” specific flavonoids were produced from accumulated P5C due to a deficiency of BmP5CR1.