Amperometric Measurements at Cells Support a Role for Dynamin in the Dilation of the Fusion Pore during Exocytosis
Artikel i vetenskaplig tidskrift, 2013

Dynamin is a GTPase mechanochemical enzyme involved in the late steps of endocytosis, where it separates the endocytotic vesicle from the cell membrane. However, recent reports have emphasized its role in exocytosis. In this case, dynamin may contribute to the control of the exocytotic pore, thus suggesting a direct control on the efflux of neurotransmitters. Dynasore, a selective inhibitor of the GTPase activity of dynamin, was used to investigate the role of dynamin in exocytosis. Exocytosis was analyzed by amperometry, thus revealing that dynasore inhibits exocytosis in a dose-dependent manner. Analysis of the exocytotic peaks shows that the inhibition of the GTPase activity of dynamin leads to shorter, smaller events. This observation, together with the rapid effect of dynasore, suggests that the blocking of the GTPase induces the formation of a more narrow and short-lived fusion pore. These results suggest that the GTPase properties of dynamin are involved in the duration and kinetics of exocytotic release. Interestingly, and in strong contrast with its role in endocytosis, the mechanochemical properties of dynamin appear to contribute to the dilation and stability of the pore during exocytosis.

bioelectrochemistry

DENSE-CORE VESICLES

exocytosis

MEMBRANE

SINGLE CELLS

QUANTAL

PC12 CELLS

VESICULAR EXOCYTOSIS

SIZE

enzymes

RELEASE

fusion pores

CHROMAFFIN CELLS

CHEMICAL-ANALYSIS

single-cell amperometry

KISS-AND-RUN

Författare

R. Trouillon

Göteborgs universitet

Andrew Ewing

Chalmers, Kemi- och bioteknik, Analytisk kemi

Göteborgs universitet

ChemPhysChem

1439-4235 (ISSN) 1439-7641 (eISSN)

Vol. 14 2295-2301

Ämneskategorier

Kemi

DOI

10.1002/cphc.201300319