The disulfide bond in chromogranin B, which is essential for its sorting to secretory granules, is not required for its aggregation in the trans-Golgi network.
FEBS Lett
; 351(2): 225-30, 1994 Sep 05.
Article
em En
| MEDLINE
| ID: mdl-8082769
ABSTRACT
Chromogranin B (secretogranin I), a protein sorted to secretory granules in many endocrine cells and neurons, undergoes selective aggregation during the sorting process in the trans-Golgi network. Reduction of the single, highly conserved intramolecular disulfide bond of chromogranin B by exposure of intact PC12 cells to the thiol reducing agent dithiothreitol has previously been shown to cause its missorting to the constitutive pathway of secretion. Using saponin perforation of membrane vesicles in aggregative buffer mimicking the milieu in the lumen of the trans-Golgi network (pH 6.4, 10 mM calcium), we show here that treatment with dithiothreitol does not prevent the aggregation of chromogranin B in this compartment. This implies that the loop in the chromogranin B polypeptide that is formed by the disulfide bond has a critical role in the membrane recognition of aggregated chromogranin B during secretory granule formation.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Compartimento Celular
/
Cromograninas
/
Grânulos Citoplasmáticos
/
Dissulfetos
/
Complexo de Golgi
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
FEBS Lett
Ano de publicação:
1994
Tipo de documento:
Article
País de afiliação:
Alemanha