TY  - JOUR
JF  - Proc. Natl. Acad. Sci. USA
AV  - public
ID  - heidok8381
TI  - Interferon messenger RNA content of human fibroblasts during induction, shutoff, and superinduction of interferon production
SP  - 3409
EP  - 3413
VL  - 74
KW  - human diploid fibroblast cells 
KW  -  poly(I)poly(C) 
KW  -  McAuslan-Tomkins translational repressor hypothesis 
KW  -  5
KW  - 6-dichloro-l-l-Dribofuranosylbenzimidazole
IS  - 8
Y1  - 1977///
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/8381/
N2  - Translation of injected mRNA in oocytes of Xenopus laevis has been used as a highly sensitive and quantitative assay for interferon mRNA. Injection into oocytes of polyadenylylated RNA extracted from poly(I)poly(C)induced human diploid fibroblasts (FS-4) leads to the synthesis of biologically active human fibroblast interferon over a period of 24-32 hr. There is a linear relationship between the amount of mRNA injected and the interferon yield obtained over a range of 1-20 ng of injected RNA. Injection of 40-80 ng of mRNA into each of 15 oocytes, homogenized in 0.3 ml of incubation medium, gave a titer of 128-256 interferon reference units/ml of homogenate. FS-4 cells at the peak of interferon production-i.e., approximately 2.5 hr after the beginning of induction with poly(I)poly(C-gave mRNA that yielded 24-48 interferon reference units/ml in the oocyte assay (30 ng of RNA injected per oocyte). An equivalent amount of mRNA from FS-4 cells in the shutoff phase, approximately 6 hr after induction, gave <4 interferon reference units/ml. In contrast, mRNA extracted from FS-4 cells that had been induced and maintained in the presence of 40 uM 5,6-dichloro-1-j-o-ribofuranosylbenzimidazole for 6 hr produced 64-128 interferon reference units/ml. Polyadenylylated RNA obtained from uninduced FS-4 cells did not lead to detectable interferon synthesis (<4 interferon reference units/ml). These data provide a direct verification of the hypothesis that the shutoff of interferon production in FS-4 cells involves a regulatory event leading to the posttranscriptional inactivation or degradation of interferon mRNA. Because the inactivating mechanism is sensitive to inhibition by 5,6-dichloro- 1--D-ribofuranosylbenzimidazole, a selective inhibitor of nuclear heterogeneous RNA and mRNA synthesis, it is likely that synthesis of an RNA molecule is necessary for the shutoff of interferon production.
A1  - Sehgal, Pravinkumar B.
A1  - Dobberstein, Bernhard
A1  - Tamm, Igor
ER  -