Role of Axonal BK channel in Cerebellar Purkinje Cells

• Project/Area Number: 26640017
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Neurophysiology / General neuroscience
• Research Institution: Doshisha University
• Principal Investigator: Misono Hiroaki 同志社大学, 脳科学研究科, 教授 (40609509)
• Co-Investigator(Renkei-kenkyūsha): Hirono Moritoshi 同志社大学, 研究開発推進機構, 特定任用研究員(准教授) (30318836) ; Watanabe Shoji 同志社大学, 研究開発推進機構, 特定任用研究員(助教) (80462745)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000); Fiscal Year 2015: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2014: ¥2,860,000 (Direct Cost: ¥2,200,000、Indirect Cost: ¥660,000)
• Keywords: チャネル / 軸索 / 活動電位 / 小脳 / イオンチャネル / 可塑性 / 小脳皮質

Outline of Final Research Achievements

Purkinje cells are the sole output of the cerebellar cortex. Therefore, to understand information processing in the cerebellar circuit for motor coordination and learning, it is necessary to understand the mechanisms regulating action potential conduction in their myelinated axons. In particular, voltage-gated potassium (Kv) channels are of importance. In this study, we found novel expression of the calcium and voltage-activated BK channel in Purkinje cell axons. Our results suggest that axonal BK channels uniquely support high-fidelity firing of action potentials in myelinated Purkinje cell axons, thereby underpinning the output of the cerebellar cortex to the deep cerebellar nuclei. They also indicate that there are dynamic changes in calcium near the nodes of Ranvier. Taken together, our research opened a new possibility that neuronal signals can be dynamically regulated in the axon.

Research Products

• [Int'l Joint Research] University of California, Davis/Baylor College of Medicine(米国)
• [Int'l Joint Research] IST Austria(Austria)
• [Journal Article] BK channels localize to the paranodal junction and regulate action potentials in myelinated axons of cerebellar Purkinje cells (2015)
  • Author(s): Moritoshi Hirono, Yasuhiro Ogawa, Kaori Misono, Daniel R. Zollinger, James S. Trimmer, Matthew N. Rasband, and Hiroaki Misonou
  • Journal Title: The Journal of Neuroscience Volume: 35 Issue: 18 Pages: 7082-7094
  • DOI: 10.1523/jneurosci.3778-14.2015
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Role of axonal BK channels in myelinated Purkinje cell axons of the cerebellum. (2015)
  • Author(s): Hirono M., Ogawa Y., Misono K., Zollinger D.R., Trimmer J.S., Rasband M.N., and Misonou H.
  • Organizer: Ion Channel Regulation, FASEB Science Research Conference
  • Place of Presentation: Montana, USA
  • Year and Date: 2015-06-28
  • Int'l Joint Research