Avtor/Urednik     Jorgačevski, J; Fošnarič, M; Vardjan, N; Stenovec, M; Potokar, M; Kreft, M; Kralj-Iglič, V; Iglič, A; Zorec, R
Naslov     Fusion pore stability of peptidergic vesicles
Tip     članek
Vir     Mol Membr Biol
Vol. in št.     Letnik 27, št. 2-3
Leto izdaje     2010
Obseg     str. 65-80
Jezik     eng
Abstrakt     It is believed that in regulated exocytosis the vesicle membrane fuses with the plasma membrane in response to a physiological stimulus. However, in the absence of stimulation, repetitive transient fusion events are also observed, reflecting a stable state. The mechanisms by which the initial fusion pore attains stability are poorly understood. We modelled energetic stability of the fusion pore by taking into account the anisotropic, intrinsic shape of the membrane constituents and their in-plane ordering in the local curvature of the membrane. We used cell-attached membrane capacitance techniques to monitor the appearance and conductance of single fusion pore events in cultured rat lactotrophs. The results revealed a bell-shaped distribution of the fusion pore conductance with a modal value of 25 pS. The experimentally observed increase of the fusion pore stability with decreasing fusion pore radius agrees well with the theoretical predictions. Moreover, the results revealed a correlation between the amplitude of transient capacitance increases and the fusion pore conductance, indicating that larger vesicles may attain a stable fusion pore with larger fusion pore diameters.
Deskriptorji     PITUITARY GLAND
EXOCYTOSIS
MEMBRANE FLUIDITY
MEMBRANE FUSION
ELECTRIC CONDUCTIVITY
RATS, WISTAR
PATCH-CLAMP TECHNIQUES
PROLACTIN
IMMUNOHISTOCHEMISTRY
CELLS, CULTURED