Interferon, double-stranded RNA, and RNA degradation. Isolation of homogeneous pppA(2'p5'A)n-1 synthetase from Ehrlich ascites tumor cells.
pppA(2'p5'A)n-1 ((2'-5')(A)n) synthetase is one of the mediators of interferon action. On activation by double-stranded RNA, it converts ATP into (2'-5')(A)n; in turn, (2'-5')(A)n activates an endonuclease (RNase L) which cleaves single-stranded RNA. We report a simple procedure for the isolation of pure (2'-5')(A)n synthetase from interferon-treated Ehrlich ascites tumor cells. The procedure involves differential precipitation of the ribosomal salt wash fraction with ammonium sulfate and chromatography on DEAE-cellulose and CM-cellulose. The apparent molecular weight of the enzyme is 105,000 as determined by gel electrophoresis in sodium dodecyl sulfate and about 85,000 when determined by centrifugation through a glycerol gradient. The size range of the (2'-5')(A)n produced by the enzyme extends from the dimer to at least the pentadecamer.
D015088:2',5'-Oligoadenylate Synthetase; D000227:Adenine Nucleotides / Q000302:isolation & purification / Q000378:metabolism; D000818:Animals; D002286:Carcinoma, Ehrlich Tumor / Q000201:enzymology*; D007372:Interferons / Q000494:pharmacology*; D051379:Mice; D008970:Molecular Weight; D009843:Oligoribonucleotides / Q000302:isolation & purification / Q000378:metabolism; D011070:Poly I-C; D011118:Polynucleotide Ligases / Q000302:isolation & purification* / Q000378:metabolism; D012313:RNA
D000227:Adenine Nucleotides; D009843:Oligoribonucleotides; D012313:RNA; D007372:Interferons; D015088:2',5'-Oligoadenylate Synthetase; D011118:Polynucleotide Ligases; D011070:Poly I-C