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PI4P and PI(4,5)P2 are essential but independent lipid determinants of membrane identity.

ABSTRACT: The quantitatively minor phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P(2)] fulfills many cellular functions in the plasma membrane (PM), whereas its synthetic precursor, phosphatidylinositol 4-phosphate (PI4P), has no assigned PM roles apart from PI(4,5)P(2) synthesis. We used a combination of pharmacological and chemical genetic approaches to probe the function of PM PI4P, most of which was not required for the synthesis or functions of PI(4,5)P(2). However, depletion of both lipids was required to prevent PM targeting of proteins that interact with acidic lipids or activation of the transient receptor potential vanilloid 1 cation channel. Therefore, PI4P contributes to the pool of polyanionic lipids that define plasma membrane identity and to some functions previously attributed specifically to PI(4,5)P(2), which may be fulfilled by a more general polyanionic lipid requirement.

SUBMITTER: Hammond GR

PROVIDER: S-EPMC3646512 | biostudies-literature | 2012 Aug

REPOSITORIES: biostudies-literature

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PI4P and PI(4,5)P2 are essential but independent lipid determinants of membrane identity.

Hammond Gerald R V GR Fischer Michael J MJ Anderson Karen E KE Holdich Jon J Koteci Ardita A Balla Tamas T Irvine Robin F RF

Science (New York, N.Y.) 20120621 6095

The quantitatively minor phospholipid phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P(2)] fulfills many cellular functions in the plasma membrane (PM), whereas its synthetic precursor, phosphatidylinositol 4-phosphate (PI4P), has no assigned PM roles apart from PI(4,5)P(2) synthesis. We used a combination of pharmacological and chemical genetic approaches to probe the function of PM PI4P, most of which was not required for the synthesis or functions of PI(4,5)P(2). However, depletion of both l ...[more]

PMID: 22722250

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2022-03-26 | PXD031266 | Pride

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