Type II PtdInsP kinases: location, regulation and function.
Type II PtdInsP kinases: location, regulation and function.
复制标题
II 型 PtdInsP 激酶：位置、调节和功能。
DOI：
10.1042/bss0740149
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
R. Irvine
中科院分区：
文献类型：
--
作者：
J. Clarke;J. Richardson;K. Hinchliffe;R. Irvine
PtdIns（4，5）P2合成的调节正变得像我们从这种脂质的多功能性质所预期的那样复杂。在本章中，我们专注于肌醇代谢的一个方面，这是II型PIPkins（II型PtdInsP激酶）的功能。这些主要是PtdIns 5 P 4-激酶，尽管在体外它们也将PtdIns 3 P磷酸化为PtdIns（3，4）P2。因此，它们具有三种不一定是排他性的功能：通过数量上次要的途径制备PtdIns（4，5）P2，去除PtdIns 5 P和通过不涉及I类PtdIns 3-激酶的途径制备PtdIns（3，4）P2。这三种可能的功能都还没有被明确证明或排除。在这三种亚型中，α和β广泛表达，II α主要在胞浆中表达，II β主要在细胞核中表达。PIPkin IIgamma具有更受限制的组织表达模式，并且似乎主要定位于细胞内囊泡。在这里，我们依次介绍三种II型PIPkin中的每一种，并讨论我们对它们的定位、调节和功能的了解。
The regulation of the synthesis of PtdIns(4,5)P2 is emerging as being as complex as we might expect from the multi-functional nature of this lipid. In the present chapter we focus on one aspect of inositide metabolism, which is the functions of the Type II PIPkins (Type II PtdInsP kinases). These are primarily PtdIns5P 4-kinases, although in vitro they will also phosphorylate PtdIns3P to PtdIns(3,4)P2. Thus they have three, not necessarily exclusive, functions: to make PtdIns(4,5)P2 by a quantitatively minor route, to remove PtdIns5P and to make PtdIns(3,4)P2 by a route that does not involve a Class I PtdIns 3-kinase. None of these three possible functions has yet been unambiguously proven or ruled out. Of the three isoforms, alpha and beta are widely expressed, the IIalpha being predominantly cytosolic and the IIbeta primarily nuclear. PIPkin IIgamma has a much more restricted tissue expression pattern, and appears to be localized primarily to intracellular vesicles. Here we introduce in turn each of the three Type II PIPkins, and discuss what we know about their localization, their regulation and their function.