Patching plasma membrane disruptions with cytoplasmic membrane.
J Cell Sci
; 113 ( Pt 11): 1891-902, 2000 Jun.
Article
en En
| MEDLINE
| ID: mdl-10806100
Vesicle-vesicle fusion initiated in cell cytoplasm by high Ca(2+) can rapidly erect large membrane boundaries. These might be used as a 'patch' for resealing plasma membrane disruptions. Three central predictions of this 'patch' hypothesis are here established in sea urchin eggs. First, we show that surface markers for plasma membrane protein and lipid are initially absent over disruption sites after resealing is complete. Second, we demonstrate that resealing capacity is strongly dependent upon local availability of fusion competent cytoplasmic organelles, specifically the reserve or yolk granule. Lastly, we demonstrate that the reserve granule is capable of rapid (t(1/2) <1 second), Ca(2+)-regulated (high threshold) fusion capable of erecting large (>1000 microm(2)), continuous membrane boundaries. Production of patch vesicles for resealing may proceed by an 'emergency' fusion mechanism distinct from that utilized for the much slower, highly regulated, cytosol-requiring organelle-organelle fusion events typical of constitutive membrane trafficking pathways.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Membrana Celular
/
Membranas Intracelulares
/
Fusión de Membrana
Límite:
Animals
Idioma:
En
Revista:
J Cell Sci
Año:
2000
Tipo del documento:
Article
País de afiliación:
Estados Unidos
Pais de publicación:
Reino Unido