Posttranscriptional regulation of albumin and alpha-fetoprotein messenger RNA by transforming growth factor-beta 1 requires de novo RNA and protein synthesis.
Mol Endocrinol
; 6(11): 1789-96, 1992 Nov.
Article
en En
| MEDLINE
| ID: mdl-1282669
ABSTRACT
Transforming growth factor-beta (TGF beta) has been implicated in the regulation of hepatocyte function. We have examined TGF beta 1 regulation of albumin and alpha-fetoprotein (AFP) mRNA levels in a well differentiated mouse hepatoma cell line (BWTG3). TGF beta 1 reversibly decreased steady state mRNA levels of both albumin and AFP. By nuclear run-on assays, we found that TGF beta 1 caused no significant change in transcription rates for albumin or AFP. Pretreatment with actinomycin-D prevented the TGF beta 1-induced decrease in albumin and AFP mRNA levels. Also, if cells were treated with actinomycin-D after a 12-h exposure to TGF beta 1, actinomycin-D abrogated the further decrease in albumin and AFP mRNA levels that occurred after treatment with TGF beta 1 alone. Cycloheximide pretreatment blocked the TGF beta 1-induced decrease in albumin and AFP mRNA levels. TGF beta 1 altered neither the rate of BWTG3 cell growth nor the levels of mRNA for the growth-associated protooncogene c-myc. These data suggest that TGF beta 1 has regulatory effects on specific hepatocyte functions that are independent of growth regulatory effects. The decrease in albumin and AFP mRNAs caused by TGF beta 1 is posttranscriptional and dependent upon de novo RNA and protein synthesis.
Buscar en Google
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
ARN Mensajero
/
Alfa-Fetoproteínas
/
Procesamiento Postranscripcional del ARN
/
Factor de Crecimiento Transformador beta
/
Albúminas
/
Hígado
Límite:
Animals
Idioma:
En
Revista:
Mol Endocrinol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
ENDOCRINOLOGIA
Año:
1992
Tipo del documento:
Article