Profilin Interaction with Phosphatidylinositol (4,5)-Bisphosphate Destabilizes the Membrane of Giant Unilamellar Vesicles

Krishnan, Kannan; Holub, Oliver; Gratton, Enrico; Clayton, Andrew H.A.; Cody, Stephen; Moens, Pierre

doi:10.1016/j.bpj.2009.03.034

Author(s)

Krishnan, Kannan

Holub, Oliver

Gratton, Enrico

Clayton, Andrew H.A.

Cody, Stephen

Moens, Pierre

Publication Date

2009

Abstract

Profilin, a small cytoskeletal protein, and phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P₂] have been implicated in cellular events that alter the cell morphology, such as endocytosis, cell motility, and formation of the cleavage furrow during cytokinesis. Profilin has been shown to interact with PI(4,5)P₂, but the role of this interaction is still poorly understood. Using giant unilamellar vesicles (GUVs) as a simple model of the cell membrane, we investigated the interaction between profilin and PI(4,5)P₂. A number and brightness analysis demonstrated that in the absence of profilin, molar ratios of PI(4,5)P₂ above 4% result in lipid demixing and cluster formations. Furthermore, adding profilin to GUVs made with 1% PI(4,5)P₂ leads to the formation of clusters of both profilin and PI(4,5)P₂. However, due to the self-quenching of the dipyrrometheneboron difluoride-labeled PI(4,5)P₂, we were unable to determine the size of these clusters. Finally, we show that the formation of these clusters results in the destabilization and deformation of the GUV membrane.

Citation

Biophysical Journal, 96(12), p. 5112-5121

ISSN

1542-0086

0006-3495

Link

https://hdl.handle.net/1959.11/3197

Language

en

Publisher

Elsevier Inc

Title

Profilin Interaction with Phosphatidylinositol (4,5)-Bisphosphate Destabilizes the Membrane of Giant Unilamellar Vesicles

Type of document

Journal Article

Entity Type

Publication

Author(s)	Krishnan, Kannan Holub, Oliver Gratton, Enrico Clayton, Andrew H.A. Cody, Stephen Moens, Pierre
Publication Date	2009
Abstract	Profilin, a small cytoskeletal protein, and phosphatidylinositol (4,5)-bisphosphate [PI(4,5)P₂] have been implicated in cellular events that alter the cell morphology, such as endocytosis, cell motility, and formation of the cleavage furrow during cytokinesis. Profilin has been shown to interact with PI(4,5)P₂, but the role of this interaction is still poorly understood. Using giant unilamellar vesicles (GUVs) as a simple model of the cell membrane, we investigated the interaction between profilin and PI(4,5)P₂. A number and brightness analysis demonstrated that in the absence of profilin, molar ratios of PI(4,5)P₂ above 4% result in lipid demixing and cluster formations. Furthermore, adding profilin to GUVs made with 1% PI(4,5)P₂ leads to the formation of clusters of both profilin and PI(4,5)P₂. However, due to the self-quenching of the dipyrrometheneboron difluoride-labeled PI(4,5)P₂, we were unable to determine the size of these clusters. Finally, we show that the formation of these clusters results in the destabilization and deformation of the GUV membrane.
Citation	Biophysical Journal, 96(12), p. 5112-5121
ISSN	1542-0086 0006-3495
Link	https://hdl.handle.net/1959.11/3197
Language	en
Publisher	Elsevier Inc
Title	Profilin Interaction with Phosphatidylinositol (4,5)-Bisphosphate Destabilizes the Membrane of Giant Unilamellar Vesicles
Type of document	Journal Article
Entity Type	Publication

Profilin Interaction with Phosphatidylinositol (4,5)-Bisphosphate Destabilizes the Membrane of Giant Unilamellar Vesicles

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