西亚试剂优势供应上万种化学试剂产品,欢迎各位新老客户咨询、选购!

登录

¥0.00

联系方式:400-990-3999 / 邮箱:sales@xiyashiji.com

西亚试剂 —— 品质可靠,值得信赖

西亚试剂:Flippase-mediated phospholipid asymmetry promotes fast Cdc4

Flippase-mediated phospholipid asymmetry promotes fast Cdc42 recycling in dynamic maintenance of cell polarity

Arupratan Das, Brian D. Slaughter, Jay R. Unruh, William D. Bradford, Richard Alexander, Boris Rubinstein & Rong Li

Lipid asymmetry at the plasma membrane is essential for such processes as cell polarity, cytokinesis and phagocytosis1, 2, 3. Here we find that a lipid flippase complex, composed of Lem3, Dnf1 or Dnf2 (ref. 4), has a role in the dynamic recycling of the Cdc42 GTPase, a key regulator of cell polarity5, in yeast. By using quantitative microscopy methods, we show that the flippase complex is required for fast dissociation of Cdc42 from the polar cortex by the guanine nucleotide dissociation inhibitor. A loss of flippase activity, or pharmacological blockage of the inward flipping of phosphatidylethanolamine, a phospholipid with a neutral head group, disrupts Cdc42 polarity maintained by guanine nucleotide dissociation inhibitor-mediated recycling. Phosphatidylethanolamine flipping may reduce the charge interaction between a Cdc42 carboxy-terminal cationic region with the plasma membrane inner leaflet, enriched for the negatively charged lipid phosphatidylserine. Using a reconstituted system with supported lipid bilayers, we show that the relative composition of phosphatidylethanolamine versus phosphatidylserine directly modulates Cdc42 extraction from the membrane by guanine nucleotide dissociation inhibitor.