Post-transcriptional effect of ultraviolet light on gene expression in human cells. Stabilization of cytokine-induced and poly(I).poly(C)-induced messenger RNA.
It is well established that ultraviolet light modulates gene expression in mammalian cells, particularly at transcriptional and post-translational levels. The present study was undertaken to investigate whether the fate of mRNA is also altered in ultraviolet-light-irradiated human cells. In order to facilitate distinction between transcriptional and post-transcriptional effects, this analysis has focused on six genes whose transcription is conditional on the supply of exogenous inducers, interferon-alpha, interleukin-1 alpha or the double-stranded RNA, poly(I).poly(C). Human cells induced to express these genes were found to retain a significantly higher concentration of corresponding transcripts when irradiated with ultraviolet light at the end of the inducing treatment. This stimulation was due to dose-dependent ultraviolet-light stabilization of preformed mRNA, as shown by run-on and pulse/chase experiments. This work uncovers a new facet of the cellular response to genotoxic stresses, i.e. extension of the life-span of transcription products. Whether this stabilizing effect contributes to cell recovery by promoting gene expression remains to be determined.
Department of Molecular Biology, Université Libre de Bruxelles, Rhode St. Genèse, Belgium.
G
G
Hilgers
I M
IM
Clauss
G A
GA
Huez
J
J
Rommelaere
D015152:Blotting, Northern; D002461:Cell Line, Transformed; D015870:Gene Expression / Q000187:drug effects / Q000528:radiation effects*; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007668:Kidney / Q000166:cytology; D011070:Poly I-C / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional / Q000528:radiation effects*; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects*; D014158:Transcription, Genetic; D014466:Ultraviolet Rays
D012333:RNA, Messenger; D007371:Interferon-gamma; D011070:Poly I-C