Sequestration of the G protein beta gamma subunit complex inhibits receptor-mediated endocytosis.
Cell surface receptors that mediate endocytosis cluster into clathrin-coated pits, which pinch off to form vesicles that transport the receptors and their ligands. This multi-step process requires the coordinated action of many factors, including GTP-hydrolyzing proteins such as dynamin and regulators of actin cytoskeleton assembly. We note herein that sequestration of heterotrimeric G protein beta gamma subunits in intact cells strongly inhibits clathrin-coated pit-mediated endocytosis and causes rearrangement of the actin cytoskeleton. Our results suggest that cells contain a pool of free beta gamma and that it functions constitutively to permit endocytosis.
Lin
H C
HC
Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75235-9041, USA.
Duncan
J A
JA
Kozasa
T
T
Gilman
A G
AG
D008841:Actin Cytoskeleton / Q000648:ultrastructure; D000199:Actins / Q000502:physiology; D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D019556:COS Cells; D003034:Coated Pits, Cell-Membrane / Q000502:physiology; D004705:Endocytosis; D019206:GTP-Binding Protein alpha Subunits, Gi-Go / Q000502:physiology*; D005822:Genetic Vectors; D011994:Recombinant Proteins; D014168:Transferrin / Q000378:metabolism
D000199:Actins; D011994:Recombinant Proteins; D014168:Transferrin; D019206:GTP-Binding Protein alpha Subunits, Gi-Go