Proton signaling mediated by voltagegated proton channels

由电压门控质子通道介导的质子信号传导

• 批准号: 14570045
• 负责人: KUNO Miyuki
• 金额: $ 2.18万
• 依托单位: Osaka City University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14570045/
• 关键词: proton channel; temperature dependence; osteoclast; cell swelling; pH regulation; proton sensor; phorbol ester; microglia; プロトンシグナル; 酸感受性

We have investigated how the voltage-gated proton (H^+) channels regulate H^+ signaling in osteoclasts, microglia and bone-marrow-derived mast cells (BMMC). The Q_<10> value was > 2.0 for conductance and 3 -6 for gating parameters. These high Q_<10> values were preserved well in both microglia and BMMC, which differed in the expression rate of the channel, implying that the high temperature dependence resides in the channel itself. The Q_<10> value for the conductance was, however, often decreased at high temperature or in swollen cells, thus, indicating that the activation status of the H^+ channel is heterogeneous. To clarify actions of the H^+ channel in intact cells, the channel activity in response to various types of cell acidosis was examined in the perforated-whole cell recordings under intrinsic pH buffers. In osteoclasts, an activator for protein kinase C, PMA, induced cell acidosis and activation of the H^+ channel. The reversal potential was served as a real-time monitor for changes in cellular pH in clamped cells. In microglia, the H^+ channel was activated accompanying either acute or prolonged cell acidosis. The channel activation terminated upon removal of the acidosis due to the H^+ extrusion. A part of the activation was, however, modified by ΔpH-independent processes. In addition, sometimes increases in intracellular Ca^<2+> or flux of CL^-, a counter ion for H^+, were associated with the acidosis. Thus H^+ signaling is intimately related to synergistic actions of other ion signals. This study has provided evidences that the H^+ can maintain cellular pH homeostasis by sensing minor changes in pH disturbances and, simultaneously, would trigger H^+ to the surrounding cells.

我们研究了电压门控质子(H^+)通道如何调节破骨细胞、小胶质细胞和骨髓源性肥大细胞(BMMC)中的H^+信号。Q_&lt；10&gt；值为电导为&gt；2.0，门控参数为3-6。这些高Q值在小胶质细胞和BMMC中都保存得很好，这两种细胞的通道表达速率不同，这意味着高温依赖存在于通道本身。然而，在高温或肿胀的细胞中，电导的Q_10&gt；值往往降低，从而表明H^+通道的激活状态是不均匀的。为了阐明H~+通道在完整细胞中的作用，在固有的pH缓冲液中，在穿孔全细胞记录中检测了不同类型细胞酸化时的通道活性。在破骨细胞中，蛋白激酶C的激活剂PMA诱导细胞酸化和H^+通道的激活。反转电位被用作钳制细胞中细胞pH变化的实时监测。在小胶质细胞中，H^+通道被激活，并伴有急性或长期的细胞酸中毒。由于H^+的挤出，当酸中毒消除时，通道激活终止。然而，部分激活被Δ不依赖于pH的过程修饰。此外，有时细胞内Ca~(2+)和Gt~(2+)或H~(2+)的拮抗剂CL~(-)流量的增加与酸中毒有关。因此，H^+信号与其他离子信号的协同作用密切相关。这项研究提供了证据，表明H~(++)可以通过感知pH扰动的微小变化来维持细胞的pH动态平衡，同时也会触发H~(++)到周围细胞。

项目成果

森泰生, 稲垣千代子, 久野みゆき, 井上隆司, 岡田泰伸, 今泉祐治: "薬理学のQOLへの貢献2:細胞増殖・分化・死を制御するイオンメカニズムと創薬"Folia Pharmacol.Jpn.. 122. 201-214 (2003)

Yasuo Mori、Chiyoko Inagaki、Miyuki Kuno、Takashi Inoue、Yasunobu Okada、Yuji Imaizumi：“药理学对 QOL 2 的贡献：控制细胞增殖、分化和死亡的离子机制和药物发现” Folia Pharmacol.Jpn.. 122 .201 -214 (2003)

Morihata, H., Mori, H., Sakai, H., Kawawaki, J., sawada, M., Tsutada, T., Kuno, M.: "Activation of voltage-gated proton channels and calcium mobilization upon acute and prolonged cell acidosis in rat micorogilia"Biophys.J.. 86. 129a (2004)

Morihata, H.、Mori, H.、Sakai, H.、Kawawaki, J.、sawada, M.、Tsutada, T.、Kuno, M.：“电压门控质子通道的激活和急性和长时间的钙动员

Shimakawa, S., Suzuki, S., Miyamoto, R., Takitani, K., Tanaka, K., Tanabe, T., Wakamiya, E., Nakamura, F., Kuno, M., Matsuura, S., Watanabe, Y., Tamai, H.: "Neuropilin-2 is overexpresed in the rat brain after limbic seizures."Brain Res.. 956. 67-73 (2002)

岛川，S.，铃木，S.，宫本，R.，泷谷，K.，田中，K.，田边，T.，若宫，E.，中村，F.，久野，M.，松浦，S.，

Mori, H., Sakai, H., Morihata, H., Yamano, T., Kuno, M.: "A voltage-gated H^+ channel is a powerful mechanism for pH homeostasis in murine steoclasts"Kobe J Med Sci. 48. 87-96 (2002)

Mori, H.、Sakai, H.、Morihata, H.、Yamano, T.、Kuno, M.：“电压门控 H^ 通道是小鼠破骨细胞 pH 稳态的强大机制”Kobe J Med Sci。

Kuno, M., Morihata, H., Mori H., Kawawaki, J.: "Effects of temperature on the voltage-gated proton channels and proton signaling"Jpn.J.Physiol.. Vol.52,Suppl.. S117 (2002)

Kuno, M.、Morihata, H.、Mori H.、Kawawaki, J.：“温度对电压门控质子通道和质子信号传导的影响”Jpn.J.Physiol.. Vol.52，Suppl.. S117（