Expression of interferon-induced genes in different tissues of mice.
In vivo responses to interferon (IFN) in mice were determined by measuring the steady-state levels of induced mRNAs following injection of IFN and poly(I)-poly(C). With cDNA probes for mouse 2'-5' oligoadenylate synthetase (2-5A synthetase) and 1-8, constitutive expression of the corresponding mRNA was detectable in different organs of normal C3H/He mice. These mRNA levels were increased by as much as 15-fold over control levels in various tissues, including the brain, after IFN and poly(I)-poly(C) treatment, coincident with increases in 2-5A synthetase enzyme activity. The basal activity level of this enzyme could be reduced in normal mice by treatment with anti-mouse IFN (alpha + beta) antibody. This treatment also reduced the levels of 2-5A synthetase and 1-8 mRNAs. Thus, physiological levels of circulating IFN maintain elevated levels of IFN-induced mRNAs in mice. Furthermore, changes in 2-5A synthetase enzyme activity reflect the changes in gene expression in vivo.
Flenniken
A M
AM
Division of Infectious Diseases, Hospital for Sick Children, Toronto, Ontario, Canada.
Galabru
J
J
Rutherford
M N
MN
Hovanessian
A G
AG
Williams
B R
BR
D015088:2',5'-Oligoadenylate Synthetase / Q000096:biosynthesis / Q000235:genetics*; D000818:Animals; D005260:Female; D005786:Gene Expression Regulation; D007370:Interferon Type I / Q000494:pharmacology*; D051379:Mice; D008809:Mice, Inbred C3H; D009693:Nucleic Acid Hybridization; D011070:Poly I-C / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis* / Q000235:genetics; D013047:Specific Pathogen-Free Organisms
D007370:Interferon Type I; D012333:RNA, Messenger; D015088:2',5'-Oligoadenylate Synthetase; D011070:Poly I-C