Article

Yeung, T. et al. Receptor activation alters inner surface potential during phagocytosis. Science 313, 347-351

University of Toronto, Toronto, Ontario, Canada
Science (Impact Factor: 33.61). 08/2006; 313(5785):347-51. DOI: 10.1126/science.1129551
Source: PubMed

ABSTRACT

The surface potential of biological membranes varies according to their lipid composition. We devised genetically encoded
probes to assess surface potential in intact cells. These probes revealed marked, localized alterations in the charge of the
inner surface of the plasma membrane of macrophages during the course of phagocytosis. Hydrolysis of phosphoinositides and
displacement of phosphatidylserine accounted for the change in surface potential at the phagosomal cup. Signaling molecules
such as K-Ras, Rac1, and c-Src that are targeted to the membrane by electrostatic interactions were rapidly released from
membrane subdomains where the surface charge was altered by lipid remodeling during phagocytosis.

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