P型和Q型钙通道的性质差异及其可能的结构基础

Differences in the properties between P-and Q-type calcium channels and their presumable structural relevance

P型和Q型钙通道虽然被发现得较晚 ,但因其在神经递质释放中的重要作用而倍受关注。构成这两类通道孔道的均为α1A亚单元 ,但它们在失活特性、对阻断剂的敏感性上有明显差异。通道α1A亚单元的相关肽段序列以及参与共表达的β亚单元的不同是这两类通道性质差异可能的结构基础。

P- and Q-type channels, the last characterized ones among the known calcium channels so far, are attracting more and more attention due to their crucial function in neurotransmitter release. It is believed that both types possess pore-forming α 1A subunit, but there are some differences between them in inactivation property and toxin sensitivity. The determinants of these differences may reside in the diversity of isoform of α 1A subunit and β-subunit coexpressing with α 1A .