Protein kinase C-mediated translocation of secretory vesicles to plasma membrane and enhancement of neurotransmitter release from PC12 cells.
In order to elucidate the molecular mechanism of phorbol ester-induced potentiation of neurotransmitter release, changes in the subcellular distribution of secretory vesicles were studied in PC12 cells. Dopamine (DA) and acetylcholine containing vesicles were selectively labelled by expressing green fluorescent protein-conjugated vesicular monoamine transporter and vesicular acetylcholine transporter, respectively. In the resting state, these vesicles were distributed throughout the cytoplasm. Phorbol-12-myristate-13-acetate (PMA), but not the inactive analogue 4 alpha-PMA, induced a redistribution of both types of secretory vesicles near the plasma membrane, and this change was abolished by a protein kinase C (PKC) inhibitor, bisindolylmaleimide I (BIS). PMA also induced a marked enhancement of depolarization-induced DA release and phosphorylation of SNAP-25 at Ser187. BIS completely inhibited PMA-induced SNAP-25 phosphorylation but suppressed PMA-induced enhancement of DA release only partially. These results suggest that PMA enhances neurotransmitter release from PC12 cells by both PKC-dependent and PKC-independent mechanisms, and PKC enhances neurotransmitter release by recruiting secretory vesicles to the plasma membrane.
Shoji-Kasai
Yoko
Y
Mitsubishi Kagaku Institute of Life Sciences, Machida, Tokyo 194-8511, Japan.
Itakura
Makoto
M
Kataoka
Masakazu
M
Yamamori
Saori
S
Takahashi
Masami
M
D000109:Acetylcholine / Q000378:metabolism; D000818:Animals; D002273:Carcinogens / Q000494:pharmacology; D002352:Carrier Proteins / Q000187:drug effects / Q000378:metabolism; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology*; D002490:Central Nervous System / Q000166:cytology / Q000201:enzymology* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D049452:Green Fluorescent Proteins; D007202:Indicators and Reagents / Q000378:metabolism; D008164:Luminescent Proteins / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000187:drug effects / Q000378:metabolism; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins / Q000187:drug effects / Q000378:metabolism; D009479:Neuropeptides; D018377:Neurotransmitter Agents / Q000378:metabolism*; D016716:PC12 Cells; D017729:Presynaptic Terminals / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D011493:Protein Kinase C / Q000187:drug effects / Q000378:metabolism*; D021381:Protein Transport / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D022142:Secretory Vesicles / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism; D013572:Synaptic Vesicles / Q000187:drug effects / Q000201:enzymology; D050825:Synaptosomal-Associated Protein 25; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D050494:Vesicular Acetylcholine Transport Proteins; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins; D033921:Vesicular Transport Proteins; D000097573:Red Fluorescent Protein
D000109:Acetylcholine; D002273:Carcinogens; D002352:Carrier Proteins; D004298:Dopamine; D004791:Enzyme Inhibitors; D049452:Green Fluorescent Proteins; D007202:Indicators and Reagents; D008164:Luminescent Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D018377:Neurotransmitter Agents; D011493:Protein Kinase C; D050825:Synaptosomal-Associated Protein 25; D013755:Tetradecanoylphorbol Acetate; D050494:Vesicular Acetylcholine Transport Proteins; D050492:Vesicular Biogenic Amine Transport Proteins; D050493:Vesicular Monoamine Transport Proteins; D033921:Vesicular Transport Proteins; D000097573:Red Fluorescent Protein; C493461:Slc18a3 protein, rat; C494210:Snap25 protein, rat