Inhibition of mRNA deadenylation and degradation by ultraviolet light.
Biol Chem
; 386(12): 1287-93, 2005 Dec.
Article
em En
| MEDLINE
| ID: mdl-16336123
ABSTRACT
Post-transcriptional mechanisms contribute to the changes in gene expression induced by cell stress. The effect of UV-B light on mRNA degradation in HeLa cells was investigated using a transcriptional chase system to determine the decay kinetics of tet-off vector-derived mRNAs containing or lacking a destabilizing AU-rich element. Degradation of both mRNAs was strongly inhibited in cells exposed to UV-B light. Removal of the poly(A)-tail, considered a crucial step in mRNA degradation, was strikingly impaired. UV light also inhibited deadenylation and degradation of endogenous mRNA of the chemoattractant cytokine interleukin (IL)-8. Both effects occurred rapidly and independently of newly induced genes. Importantly, stabilization of IL-8 mRNA was accompanied by a strong increase in the duration of IL-8 protein formation. Furthermore, general inhibition of protein synthesis, a hallmark of the response to cell stress, required far higher doses of UV-B than inhibition of mRNA deadenylation and degradation. The difference in sensitivity of cells to these effects of UV-B light establishes a dose range in which mRNA stabilization can lead to dramatically enhanced expression of proteins derived from normally unstable mRNAs, such as those of inflammatory cytokines, growth factors and proto-oncogenes, and thereby have a major impact on the response to UV light.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Raios Ultravioleta
/
RNA Mensageiro
/
Adenina
/
Estabilidade de RNA
Limite:
Humans
Idioma:
En
Revista:
Biol Chem
Assunto da revista:
BIOQUIMICA
Ano de publicação:
2005
Tipo de documento:
Article
País de afiliação:
Alemanha