Phosphatidylinositol 5-phosphate 4-kinase type-2 alpha

Definition:

Catalyzes the phosphorylation of phosphatidylinositol 5-phosphate (PtdIns5P) on the fourth hydroxyl of the myo-inositol ring, to form phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). Has both ATP- and GTP-dependent kinase activities. May exert its function by regulating the levels of PtdIns5P, which functions in the cytosol by increasing AKT activity and in the nucleus signals through ING2. May regulate the pool of cytosolic PtdIns5P in response to the activation of tyrosine phosphorylation (By similarity). Required for lysosome-peroxisome membrane contacts and intracellular cholesterol transport through modulating peroxisomal PtdIns(4,5)P2 level. In collaboration with PIP4K2B, has a role in mediating autophagy in times of nutrient stress (By similarity). Required for autophagosome-lysosome fusion and the regulation of cellular lipid metabolism. May be involved in thrombopoiesis, and the terminal maturation of megakaryocytes and regulation of their size (By similarity). Negatively regulates insulin signaling through a catalytic-independent mechanism. PIP4Ks interact with PIP5Ks and suppress PIP5K-mediated PtdIns(4,5)P2 synthesis and insulin-dependent conversion to PtdIns(3,4,5)P3.

References:

[1]. L E Rameh, et al. A new pathway for synthesis of phosphatidylinositol-4,5-bisphosphate. Nature. 1997 Nov 13;390(6656):192-6. [Content Brief]

[2]. Diana G Wang, et al. PIP4Ks Suppress Insulin Signaling through a Catalytic-Independent Mechanism. Cell Rep. 2019 May 14;27(7):1991-2001.e5. [Content Brief]

[3]. Ao Hu, et al. PIP4K2A regulates intracellular cholesterol transport through modulating PI(4,5)P2 homeostasis. J Lipid Res. 2018 Mar;59(3):507-514. [Content Brief]

[4]. Kazutaka Sumita, et al. The Lipid Kinase PI5P4Kβ Is an Intracellular GTP Sensor for Metabolism and Tumorigenesis. Mol Cell. 2016 Jan 21;61(2):187-98. [Content Brief]

[5]. Andrew Wilcox, et al. Regulation of extranuclear PtdIns5P production by phosphatidylinositol phosphate 4-kinase 2alpha. FEBS Lett. 2008 Apr 16;582(9):1391-4. [Content Brief]

[6]. Mindy I Davis, et al. A homogeneous, high-throughput assay for phosphatidylinositol 5-phosphate 4-kinase with a novel, rapid substrate preparation. PLoS One. 2013;8(1):e54127. [Content Brief]

Biomedical Dictionary

The Biomedical Dictionary is a comprehensive and professional collection of biological academic terms and subject datas. All explanations are supported by authoritative books or high impact factor literatures, and you can acquire accurate explanations of the biomedical terms you want to know.

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #

Name
Email *

	Sorry, but the email address you supplied was invalid.