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Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics

How fusion pore formation during exocytosis affects the subsequent release of vesicle contents remains incompletely understood. It is unclear if the amount released per vesicle is dependent upon the nature of the developing fusion pore and whether full fusion and transient kiss and run exocytosis ar...

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Autores principales: Zanin, Mark P., Phillips, Lucy, Mackenzie, Kimberly D., Keating, Damien J.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Public Library of Science 2011
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3220683/
https://www.ncbi.nlm.nih.gov/pubmed/22125627
http://dx.doi.org/10.1371/journal.pone.0027820
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author Zanin, Mark P.
Phillips, Lucy
Mackenzie, Kimberly D.
Keating, Damien J.
author_facet Zanin, Mark P.
Phillips, Lucy
Mackenzie, Kimberly D.
Keating, Damien J.
author_sort Zanin, Mark P.
collection PubMed
description How fusion pore formation during exocytosis affects the subsequent release of vesicle contents remains incompletely understood. It is unclear if the amount released per vesicle is dependent upon the nature of the developing fusion pore and whether full fusion and transient kiss and run exocytosis are regulated by similar mechanisms. We hypothesise that if consistent relationships exist between these aspects of exocytosis then they will remain constant across any age. Using amperometry in mouse chromaffin cells we measured catecholamine efflux during single exocytotic events at P0, 1 month and 6 months. At all ages we observed full fusion (amperometric spike only), full fusion preceded by fusion pore flickering (pre-spike foot (PSF) signal followed by a spike) and pure “kiss and run” exocytosis (represented by stand alone foot (SAF) signals). We observe age-associated increases in the size of all 3 modes of fusion but these increases occur at different ages. The release probability of PSF signals or full spikes alone doesn't alter across any age in comparison with an age-dependent increase in the incidence of “kiss and run” type events. However, the most striking changes we observe are age-associated changes in the relationship between vesicle size and the membrane bending energy required for exocytosis. Our data illustrates that vesicle size does not regulate release probability, as has been suggested, that membrane elasticity or flexural rigidity change with age and that the mechanisms controlling full fusion may differ from those controlling “kiss and run” fusion.
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spelling pubmed-32206832011-11-28 Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics Zanin, Mark P. Phillips, Lucy Mackenzie, Kimberly D. Keating, Damien J. PLoS One Research Article How fusion pore formation during exocytosis affects the subsequent release of vesicle contents remains incompletely understood. It is unclear if the amount released per vesicle is dependent upon the nature of the developing fusion pore and whether full fusion and transient kiss and run exocytosis are regulated by similar mechanisms. We hypothesise that if consistent relationships exist between these aspects of exocytosis then they will remain constant across any age. Using amperometry in mouse chromaffin cells we measured catecholamine efflux during single exocytotic events at P0, 1 month and 6 months. At all ages we observed full fusion (amperometric spike only), full fusion preceded by fusion pore flickering (pre-spike foot (PSF) signal followed by a spike) and pure “kiss and run” exocytosis (represented by stand alone foot (SAF) signals). We observe age-associated increases in the size of all 3 modes of fusion but these increases occur at different ages. The release probability of PSF signals or full spikes alone doesn't alter across any age in comparison with an age-dependent increase in the incidence of “kiss and run” type events. However, the most striking changes we observe are age-associated changes in the relationship between vesicle size and the membrane bending energy required for exocytosis. Our data illustrates that vesicle size does not regulate release probability, as has been suggested, that membrane elasticity or flexural rigidity change with age and that the mechanisms controlling full fusion may differ from those controlling “kiss and run” fusion. Public Library of Science 2011-11-18 /pmc/articles/PMC3220683/ /pubmed/22125627 http://dx.doi.org/10.1371/journal.pone.0027820 Text en Zanin et al. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.
spellingShingle Research Article
Zanin, Mark P.
Phillips, Lucy
Mackenzie, Kimberly D.
Keating, Damien J.
Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title_full Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title_fullStr Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title_full_unstemmed Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title_short Aging Differentially Affects Multiple Aspects of Vesicle Fusion Kinetics
title_sort aging differentially affects multiple aspects of vesicle fusion kinetics
topic Research Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3220683/
https://www.ncbi.nlm.nih.gov/pubmed/22125627
http://dx.doi.org/10.1371/journal.pone.0027820
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