Expression cloning of 2-5A-dependent RNAase: a uniquely regulated mediator of interferon action.
2-5A-dependent RNAase, an interferon-induced enzyme that is activated by 5'-phosphorylated, 2',5'-linked oligoadenylates (2-5A), is implicated in both the molecular mechanisms of interferon action and the fundamental control of RNA stability in mammalian cells. Here we report the expression cloning and analysis of murine and human 2-5A-dependent RNAases. The 2-5A binding properties and RNAse activities of recombinant and naturally occurring forms of 2-5A-dependent RNAase were identical. Interferon induction of 2-5A-dependent RNAse expression was demonstrated by measuring the mRNA levels in cells treated with interferon and cycloheximide. Analysis of aligned murine and human 2-5A-dependent RNAse sequences revealed several intriguing features, including similarity to RNAase E, which is implicated in the control of mRNA stability in E. coli. Interestingly, a duplicated phosphate-binding loop motif was determined by deletion analysis and site-directed mutagenesis to function in the binding of 2-5A.
Zhou
A
A
Department of Cancer Biology, Cleveland Clinic Foundation, Ohio 44195.
Hassel
B A
BA
Silverman
R H
RH
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D001667:Binding, Competitive; D002460:Cell Line; D003001:Cloning, Molecular; D003513:Cycloheximide / Q000494:pharmacology; D004722:Endoribonucleases / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D007372:Interferons / Q000037:antagonists & inhibitors / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000032:analysis; D011994:Recombinant Proteins / Q000737:chemistry; D012091:Repetitive Sequences, Nucleic Acid; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D012333:RNA, Messenger; D011994:Recombinant Proteins; D007372:Interferons; D003513:Cycloheximide; D004722:Endoribonucleases; C031956:2-5A-dependent ribonuclease