Physical mobilization of secretory vesicles facilitates neuropeptide release by nerve growth factor-differentiated PC12 cells.
It has been speculated that neurosecretion can be enhanced by increasing the motion, and hence, the availability of cytoplasmic secretory vesicles. However, facilitator-induced physical mobilization of secretory vesicles has not been observed directly in living cells, and recent experimental results call this hypothesis into question. Here, high resolution green fluorescent protein (GFP)-based measurements in nerve growth factor-differentiated PC12 cells are used to test whether altering dense core vesicle (DCV) motion affects neuropeptide release. Experiments with mycalolide B and jasplakinolide demonstrate that neuropeptidergic DCV motion at the ends of processes is proportional to F-actin. Furthermore, Ba2+ increases DCV mobility without detectably modifying F-actin. Finally, we show that altering DCV motion by changing F-actin or stimulating with Ba2+ proportionally changes sustained neuropeptide release. Therefore, increasing DCV mobility facilitates prolonged neuropeptide release.
Department of Pharmacology, E1351 Biomedical Science Tower, University of Pittsburgh, Pittsburgh, PA 15261, USA.
Yuen-Keng
YK
Ng
Xinghua
X
Lu
Edwin S
ES
Levitan
D000199:Actins / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology; D002454:Cell Differentiation / Q000187:drug effects*; D047630:Depsipeptides; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins; D008164:Luminescent Proteins / Q000378:metabolism; D008387:Marine Toxins; D009068:Movement; D020932:Nerve Growth Factor / Q000494:pharmacology*; D009479:Neuropeptides / Q000378:metabolism*; D010080:Oxazoles / Q000494:pharmacology; D016716:PC12 Cells; D010456:Peptides, Cyclic / Q000494:pharmacology; D010673:Pheochromocytoma; D051381:Rats; D011994:Recombinant Proteins / Q000378:metabolism; D022142:Secretory Vesicles / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure
D000199:Actins; D000970:Antineoplastic Agents; D047630:Depsipeptides; D008164:Luminescent Proteins; D008387:Marine Toxins; D009479:Neuropeptides; D010080:Oxazoles; D010456:Peptides, Cyclic; D011994:Recombinant Proteins; C057531:jasplakinolide; C080978:mycalolide B; D049452:Green Fluorescent Proteins; D020932:Nerve Growth Factor