Roles of TASK channels in the modulation of jaw-closing motoneuron activity

2015 Fiscal Year Final Research Report

• Project/Area Number: 24592797
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Functional basic dentistry
• Research Institution: Kagoshima University (2015); Osaka University (2012-2014)
• Principal Investigator: Saito Mitsuru 鹿児島大学, 医歯学域歯学系, 教授 (50347770)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 口腔生理学 / 咬合 / 閉口筋 / 運動単位 / 序列動員 / 張力調節 / TASKチャネル / 三叉神経

Outline of Final Research Achievements

The mastication of foods occurs during the slow-closing phase of the mastication cycle, in which isometric contraction of jaw-closing muscles is developed through the rank-ordered recruitment of jaw-closing motoneurons (MNs). However, its molecular mechanism remains unknown. Here we show that TWIK-related acid-sensitive K+ channel-1 (TASK1) and TASK3 channels, which determine the input resistance and resting membrane potential, are differentially expressed between small and large MNs and play critical roles in the rank-ordered recruitment of jaw-closing MNs. The principle of the rank-ordered recruitment was originally proposed based on the conduction velocity of the motor nerve fibers innervating a set of muscle fibers. After a half-century, we for the first time disclosed the molecular mechanism for the rank-ordered recruitment of jaw-closing MNs.

Free Research Field

神経生理学