Transcriptional and posttranscriptional control in synthesis of growth marker polypeptides in mouse parotids.
The chronic daily administration of isoproterenol provokes in mouse parotid glands the induction and progressive accumulation of a family of secretory polypeptides named polypeptides C, D, E, F, and G (polypeptides C-G). These polypeptides, which seem to be part of the family of proline-rich proteins, have been considered as molecular markers of the growth-in-size response in the mouse parotid acinar cells. In the present study, two pharmacological approaches were used to determine whether the induction and the postsecretory reappearance of polypeptides C-G may be distinguished from each other. First, actinomycin D, a transcriptional inhibitor, was found to interfere with the induction by isoproterenol but not with the postsecretory reappearance. Second, pilocarpine, a secretagogue that was found to be a very weak inducer of polypeptides C-G, was able to provoke secretion and then reappearance of the whole group of isoproterenol-induced polypeptides. Accordingly, these data suggest that the induction of polypeptides C-G is dependent on transcriptional activity and that it is unrelated to secretion stimulation. By contrast, the postsecretory reappearance of polypeptides C-G may occur even when transcriptional activity is inhibited and it would be related to the secretory activity.
López Solís
R O
RO
Department of Cell Biology and Genetics, Faculty of Medicine, University of Chile, Santiago.
González
M J
MJ
Castillo
L
L
Peña y Lillo
S
S
Alliende
C
C
D000818:Animals; D015415:Biomarkers; D003609:Dactinomycin / Q000494:pharmacology; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D051379:Mice; D010306:Parotid Gland / Q000254:growth & development / Q000378:metabolism*; D010455:Peptides / Q000037:antagonists & inhibitors / Q000378:metabolism*; D010862:Pilocarpine / Q000494:pharmacology; D013997:Time Factors; D014158:Transcription, Genetic
D015415:Biomarkers; D010455:Peptides; D010862:Pilocarpine; D003609:Dactinomycin; D007545:Isoproterenol