Adaptive lipid packing and bioactivity in membrane domains
Erdinc Sezgin1, Theresia Gutmann2, Tomasz Buhl3
1Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom; Max Planck Institute for Molecular Cell Biology and Genetics, Dresden, Germany.
Plos One
|April 24, 2015
Summary
Cellular membranes exhibit diverse lipid packing states that cells actively tune. These dynamic membrane states control molecular organization and function, impacting cellular processes like insulin secretion.
Area of Science:
- Cellular biology
- Biophysics
- Membrane biophysics
Background:
- Cellular membranes display lateral heterogeneity across scales.
- Lipid rafts, ordered domains in plasma membranes, remain poorly defined in live cells regarding size, lifetime, and composition.
Purpose of the Study:
- To investigate the dynamic nature and functional relevance of lipid packing states in cellular membranes.
- To demonstrate how cells actively tune membrane organization and its impact on molecular partitioning and bioactivity.
Main Methods:
- Analysis of lipid packing states in synthetic and natural plasma membranes.
- Observation of membrane state adaptation during stimulated insulin secretion.
- Assessment of molecular partitioning and bioactivity within different membrane domains.
Main Results:
- Both synthetic and natural membranes exhibit a spectrum of lipid packing states with variable molecular order.
- Cells actively adapt and tune these membrane states during cellular processes, exemplified by insulin secretion.
- These tunable membrane states regulate molecular partitioning and the bioactivity of membrane-bound molecules, such as GM1 receptor ligand binding.
Conclusions:
- Cellular membranes possess a complex and flexible organization driven by lipid dynamics.
- Cells can functionally utilize this membrane flexibility to regulate molecular interactions and cellular functions.
- The study provides insights into the dynamic regulation of membrane organization and its role in cellular signaling.
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