Abstract
A large proportion of proteins are expected to interact with cellular membranes to carry out their physiological functions in processes such as membrane transport, morphogenesis, cytoskeletal organization, and signal transduction. The recruitment of proteins at the membrane–cytoplasm interface and their activities are precisely regulated by phosphoinositides, which are negatively charged phospholipids found on the cytoplasmic leaflet of cellular membranes and play critical roles in membrane homeostasis and cellular signaling. Thus, it is important to reveal which proteins interact with phosphoinositides and to elucidate the underlying mechanisms. Here, we present two standard in vitro methods, liposome co-sedimentation and co-flotation assays, to study lipid–protein interactions. Liposomes can mimic various biological membranes in these assays because their lipid compositions and concentrations can be varied. Thus, in addition to mechanisms of lipid–protein interactions, these methods provide information on the possible specificities of proteins toward certain lipids such as specific phosphoinositide species and can hence shed light on the roles of membrane interactions on the functions of membrane-associated proteins.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Roth MG (2004) Phosphoinositides in constitutive membrane traffic. Physiol Rev 84:699–730
Picas L, Gaits-Iacovoni F, Goud B (2016) The emerging role of phosphoinositide clustering in intracellular trafficking and signal transduction. F1000Res 5
Saarikangas J, Zhao H, Pykäläinen A et al (2009) Molecular mechanisms of membrane deformation by I-BAR domain proteins. Curr Biol 19:95–107
Senju Y, Lappalainen P (2019) Regulation of actin dynamics by PI(4,5)P2 in cell migration and endocytosis. Curr Opin Cell Biol 56:7–13
Rohatgi R, Ho HY, Kirschner MW (2000) Mechanism of N-WASP activation by CDC42 and phosphatidylinositol 4, 5-bisphosphate. J Cell Biol 150:1299–1310
Hamada K, Shimizu T, Matsui T et al (2000) Structural basis of the membrane-targeting and unmasking mechanisms of the radixin FERM domain. EMBO J 19:4449–4462
Papayannopoulos V, Co C, Prehoda KE et al (2005) A polybasic motif allows N-WASP to act as a sensor of PIP(2) density. Mol Cell 17:181–191
Zhao H, Michelot A, Koskela EV et al (2013) Membrane-sculpting BAR domains generate stable lipid microdomains. Cell Rep 4:1213–1223
Prévost C, Zhao H, Manzi J et al (2015) IRSp53 senses negative membrane curvature and phase separates along membrane tubules. Nat Commun 6:8529
Simunovic M, Manneville J-B, Renard H-F et al (2017) Friction mediates scission of tubular membranes Scaffolded by BAR proteins. Cell 170:172–184.e11
Pykäläinen A, Boczkowska M, Zhao H et al (2011) Pinkbar is an epithelial-specific BAR domain protein that generates planar membrane structures. Nat Struct Mol Biol 18:902–907
Senju Y, Kalimeri M, Koskela EV et al (2017) Mechanistic principles underlying regulation of the actin cytoskeleton by phosphoinositides. Proc Natl Acad Sci U S A 114:E8977–E8986
Acknowledgments
This work was supported by grants from the Academy of Finland (H.Z. and P.L.), Jane and Aatos Erkko Foundation (H.Z.), Guangxi distinguished expert funding (H.Z.), FY 2015 Researcher Exchange Program between JSPS and AF (Y.S.), Astellas Foundation for Research on Metabolic Disorders (Y.S.), The Scandinavia-Japan Sasakawa Foundation (Y.S.), The Ichiro Kanehara Foundation for the Promotion of Medical Sciences and Medical Care (Y.S.), The Association for Fordays Self-Reliance Support in Japan (Y.S.), The Futaba Research Grant Program of the Futaba Foundation (Y.S.), The NOVARTIS Foundation (Japan) for the Promotion of Science (Y.S.), Okayama Foundation for Science and Technology (Y.S.), Wesco Scientific Promotion Foundation (Y.S.), and JSPS KAKENHI Grant Numbers JP19K23727, JP20K06589 (Y.S.).
Author information
Authors and Affiliations
Corresponding authors
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2021 Springer Science+Business Media, LLC, part of Springer Nature
About this protocol
Cite this protocol
Senju, Y., Lappalainen, P., Zhao, H. (2021). Liposome Co-sedimentation and Co-flotation Assays to Study Lipid–Protein Interactions. In: Botelho, R.J. (eds) Phosphoinositides. Methods in Molecular Biology, vol 2251. Humana, New York, NY. https://doi.org/10.1007/978-1-0716-1142-5_14
Download citation
DOI: https://doi.org/10.1007/978-1-0716-1142-5_14
Published:
Publisher Name: Humana, New York, NY
Print ISBN: 978-1-0716-1141-8
Online ISBN: 978-1-0716-1142-5
eBook Packages: Springer Protocols