Regional Differences in Methyl Farnesoate Production by the Lobster Mandibular Organ.
Biol Bull
; 186(1): 9-16, 1994 Feb.
Article
em En
| MEDLINE
| ID: mdl-29283303
ABSTRACT
Visual examination of the mandibular organ (MO) from the lobster, Homarus americanus, disclosed two distinct morphological regions a fan-folded region along one edge of the gland, and a smooth, unfolded region comprising the rest of the gland. Because MOs produce methyl farnesoate (MF), the MF content of both regions was measured. In freshly dissected glands, more than 95% of the MF was found in the fan-folded region of the gland. In MO sections incubated with [3H-methyl]methionine (a radiolabeled precursor of MF), more than 90% of MF synthesis was found in the fan-folded region. Eyestalk ablation, a procedure that increases MO activity, caused the MF content of MOs to increase more than 130-fold, but had little effect on the regional distribution of MF. Histological observations indicated that these two regions had different cellular compositions. The fan-folded region contained two cell types (A and B). The A cells were mitotically active and appeared to be undifferentiated. The B cells contained a large number of small vacuoles. The unfolded region was largely composed of a third cell type (C). The C cells were large and morphologically complex, containing many mitochondria and large vacuolar-like structures. They contained relatively few small vacuoles. On the basis of appearance and location, B cells appear to be the likely site of MF synthesis. The physiological importance of C cells is unknown.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Biol Bull
Ano de publicação:
1994
Tipo de documento:
Article