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Title: A novel homeostatic mechanism tunes PI(4,5)P2-dependent signaling at the plasma membrane
ABSTRACT The lipid molecule phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P2] controls all aspects of plasma membrane (PM) function in animal cells, from its selective permeability to the attachment of the cytoskeleton. Although disruption of PI(4,5)P2 is associated with a wide range of diseases, it remains unclear how cells sense and maintain PI(4,5)P2 levels to support various cell functions. Here, we show that the PIP4K family of enzymes, which synthesize PI(4,5)P2 via a minor pathway, also function as sensors of tonic PI(4,5)P2 levels. PIP4Ks are recruited to the PM by elevated PI(4,5)P2 levels, where they inhibit the major PI(4,5)P2-synthesizing PIP5Ks. Perturbation of this simple homeostatic mechanism reveals differential sensitivity of PI(4,5)P2-dependent signaling to elevated PI(4,5)P2 levels. These findings reveal that a subset of PI(4,5)P2-driven functions might drive disease associated with disrupted PI(4,5)P2 homeostasis.  more » « less
Award ID(s):
2048060
PAR ID:
10488845
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
The Company of Biologists Ltd
Date Published:
Journal Name:
Journal of Cell Science
Volume:
136
Issue:
16
ISSN:
0021-9533
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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