Understanding Ca sensing receptor-loaded vesicle in parathyroid glands

2014 Fiscal Year Final Research Report

• Project/Area Number: 26670108
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: General physiology
• Research Institution: Foundation for Biomedical Research and Innovation
• Principal Investigator: IMURA Akihiro 公益財団法人先端医療振興財団, 医薬品研究開発部, 研究員 (60362513)
• Project Period (FY): 2014-04-01 – 2015-03-31
• Keywords: ミネラル代謝 / 副甲状腺 / カルシウム受容体 / テトラスパニン

Outline of Final Research Achievements

We’ve discovered unique intracellular vesicle condensing calcium sensing receptor in the parathyroid gland cells. Because tspan8 was found as an important component of the vesicle, we created parathyroid tissue-specific Tspan8-knockout mice to check the physiological function of tspan8 in mineral metabolism. Serum calcium ion level was increased at about 1.5 fold compared with that of WT mice, suggesting Tspan8 in parathyroid gland should be pivotal to maintain mineral level in vivo. Different from CaR-KOM, tspan8-KOM appeared almost healthy. Moreover, we found may extraordinarily huge vesicles like vacuolae in parathyroid cells by TEM technology. These findings revealed that tspan8 plays an important role in mineral homeostasis, especially in calcium sensing apparatus. Accordingly, tetraspanin 8-composed vesicle must function as a mineral sensing circumstance that should make sense of the extracellular fluid enclosed in the space.

Free Research Field

生理学、分子生物学