The circadian clock in fractured mouse femur

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K20012
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Orthopaedic surgery
• Research Institution: Kyoto Prefectural University of Medicine
• Principal Investigator: Minami Yoichi 京都府立医科大学, 医学(系)研究科(研究院), 助教 (40415310)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: 概日リズム / 体内時計 / 発光イメージング / 軟骨 / 骨折モデル

Outline of Final Research Achievements

The circadian clock in the cartilage formed in bone fracture healing site was studied. For this purpose, mouse femur fracture healing model was developed using PER2::Luc knock-in mouse which harbors circadian clock reporter gene. By real-time bioluminescence imaging with organ culture technique, circadian rhythm of bioluminescence in fracture healing sites were clearly detected. Noteworthy, this PER2::Luc activity rhythm was reset by parathyroid hormone (PTH).
To understand cartilage clock in detail, in vitro assay system were established using ATDC5 cell line. By real-time bioluminescence monitoring, stably transfected molecular clock reporter, Bmal1-Luc, clearly show circadian rhythms. Furthermore, as same as cartilage clock in femur growth plate and in fracture healing sites, PTH can reset the circadian clock in ATDC5. These suggest that this assay system using ATDC5 contribute for understanding the cartilage circadian clock function.

Free Research Field

環境生理学