Molecular oscillatory mechanism of the circadian clock in a hemimetabolous insect

2017 Fiscal Year Final Research Report

• Project/Area Number: 15H04400
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Animal physiology/Animal behavior
• Research Institution: Okayama University
• Principal Investigator: TOMIOKA Kenji 岡山大学, 自然科学研究科, 教授 (30136163)
• Co-Investigator(Renkei-kenkyūsha): MATSUMOTO Akira 順天堂大学, 医学部, 准教授 (40229539)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 昆虫 / 概日時計 / 時計遺伝子 / 分子振動機構 / フィードバックループ / 概日リズム

Outline of Final Research Achievements

The circadian clock is an endogenous oscillatory mechanism with a period of approximately 24 hours and temporally regulates various physiological functions in animals. In the present study, the molecular oscillatory mechanism of the clock was investigated in a hemimetabolus insect, the cricket, Gryllus bimaculatus. Results showed that the clock consists of multiple oscillatory loops regulating rhythmic expression of so-called clock genes with key transcriptional factors, Clock and cycle. The first loop regulates rhythmic expression of period and timeless. In addition, cycle seemed to be regulated by HR3 and E75, and cry2 forms a loop with various combination of its transcriptional variants and cry1. These oscillatory loops are modulated by two factors, clockwork orange and timeless2. Thus, the circadian clock of hemimetabolous insects seems more complex than that of holometabolous insects such as fruit flies.

Free Research Field

時間生物学