Regulation of exocytosis in chromaffin cells by phosducin-like protein, a protein interacting with G protein betagamma subunits.
Phosducin and related proteins have been identified as ubiquitous regulators of signalling mediated by betagamma subunits of trimeric G proteins. To explore a role for phosducin in regulated exocytosis, we have examined the distribution and putative function of phosducin-like protein (PhLP) in adrenal medullary chromaffin cells. The full-length cDNA encoding the short splice variant of PhLP (PhLPs) was cloned from cultured chromaffin cells. Native PhLPs was found associated with plasma membranes and detected in the subplasmalemmal area of resting chromaffin cells by confocal immunofluorescence analysis. Stimulation with secretagogues triggered a massive redistribution of PhLPs into the cytoplasm. When microinjected into individual chromaffin cells, recombinant PhLPs inhibited catecholamine secretion evoked by a depolarizing concentration of K+ without affecting calcium mobilization. Thus, PhLPs may participate directly in the regulation of calcium-evoked exocytosis.
Gensse
M
M
Institut National de la Santé et de la Recherche Médicale, U-338 Biologie de la Communication Cellulaire, Strasbourg, France.
Vitale
N
N
Chasserot-Golaz
S
S
Bader
M F
MF
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D002462:Cell Membrane; D002478:Cells, Cultured; D019439:Chromaffin Cells / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D018076:DNA, Complementary; D005089:Exocytosis / Q000502:physiology*; D044387:GTP-Binding Protein beta Subunits; D044388:GTP-Binding Protein gamma Subunits; D020962:Heterotrimeric GTP-Binding Proteins / Q000378:metabolism*; D006801:Humans; D018832:Molecular Chaperones; D008969:Molecular Sequence Data; D009419:Nerve Tissue Proteins / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D021381:Protein Transport; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000502:physiology
D002352:Carrier Proteins; D018076:DNA, Complementary; C118981:G-protein Beta gamma; D044387:GTP-Binding Protein beta Subunits; D044388:GTP-Binding Protein gamma Subunits; D018832:Molecular Chaperones; D009419:Nerve Tissue Proteins; C098789:PDCL protein, human; C498320:Pdcl protein, rat; D011993:Recombinant Fusion Proteins; D020962:Heterotrimeric GTP-Binding Proteins