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P4-ATPases: lipid flippases in cell membranes
Pflugers Archiv : European Journal of Physiology
|October 1, 2013
Summary
P4-ATPases are essential ATP-driven lipid flippases that maintain membrane asymmetry. These transporters move various lipids, impacting cell functions like membrane traffic and signaling.
Area of Science:
- Biochemistry
- Cell Biology
- Molecular Biology
Background:
- Eukaryotic plasma membranes utilize specialized proteins to generate lipid asymmetry.
- P4-ATPases, a subfamily of P-type ATPases, function as ATP-driven lipid flippases.
Purpose of the Study:
- To review the fundamental characteristics of P4-ATPases.
- To summarize the physiological consequences of P4-ATPase lipid transport activity.
Main Methods:
- Literature review of P4-ATPase research.
- Analysis of substrate specificities and cellular functions.
Main Results:
- P4-ATPases translocate phospholipids across membrane leaflets.
- Substrate specificity extends beyond aminophospholipids to lysophospholipids and alkylphospholipids.
- P4-ATPases influence membrane traffic, cytoskeletal dynamics, cell division, lipid metabolism, and signaling.
Conclusions:
- P4-ATPases are crucial for establishing and maintaining membrane lipid asymmetry.
- Their diverse lipid transport roles are integral to various cellular processes.
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