How does scramblase scrm regulate the distribution of phosphatidylserine in the plasma membrane?
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Phospholipid scramblases play a crucial role in regulating the distribution of phosphatidylserine (PtdSer) in the plasma membrane. Scrm-1, a plasma membrane protein, is involved in the externalization of PtdSer during apoptosis in Caenorhabditis elegans . TMEM16F, another scramblase, is responsible for plasma membrane repair after injury by pore-forming agents . The C-terminal helix of SCRM-1 is important for its membrane insertion and modulation of scrambling activity through interaction with cholesterol . The reduction in scramblase activity of hPLSCR1 is partly due to its high-affinity binding to cholesterol . The functional mechanism and physiological roles of phospholipid scramblases are being elucidated, including their involvement in blood clotting, clearance of apoptotic cells, and control of infection .
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3 Citations | The paper does not provide information on how SCRM-1 regulates the distribution of phosphatidylserine in the plasma membrane. |
62 Citations | Scramblase proteins, such as TMEM16F, act as phospholipid scramblases and quickly scramble phospholipids between lipid bilayers, allowing for the exposure of phosphatidylserine in the plasma membrane. |
52 Citations | Scramblase TMEM16F induces rapid lipid scrambling in the plasma membrane, leading to the exposure of phosphatidylserine and subsequent repair of the membrane after pore formation. |
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