Cell type-specific sorting of neuropeptides: a mechanism to modulate peptide composition of large dense-core vesicles.
J Neurosci
; 16(24): 7930-40, 1996 Dec 15.
Article
em En
| MEDLINE
| ID: mdl-8987821
ABSTRACT
The CNS of Lymnaea stagnalis contains two populations of egg-laying hormone (ELH)-producing neurons that differ in size and topology. In type I neurons, all peptides located C-terminally from the cleavage site Arg-Ser-Arg-Arg180-183 are sorted into secretory large dense-core vesicles (LDCV), whereas N-terminal-located peptides accumulate in a distinct type of vesicle, the large electrondense granule (LEG). Via immunoelectron microscopy, we now show that the second population of ELH-producing neurons, type II neurons, lack LEG and incorporate all proELH-derived peptides into LDCV. This finding provides the first example of a cell type-specific sorting of neuropeptides into LDCV. Furthermore, we provide evidence that LEG are formed through a differential condensation process in the trans-Golgi network and that these bodies are ultimately degraded. Analysis of the endoprotease composition of the two types of proELH-producing neurons suggests that the formation of LEG, and consequently the retention of N-terminal peptides from the secretory pathway, requires the action of a furin-like protein.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Neuropeptídeos
/
Hormônios de Invertebrado
/
Neurônios
Limite:
Animals
Idioma:
En
Ano de publicação:
1996
Tipo de documento:
Article