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In vitro Synthesis of Viral RNA by the Poliovirus RNA Polymerase

Baltimore, David (1964) In vitro Synthesis of Viral RNA by the Poliovirus RNA Polymerase. Proceedings of the National Academy of Sciences of the United States of America, 51 (3). pp. 450-456. ISSN 0027-8424. doi:10.1073/pnas.51.3.450.

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Infection of cultured mammalian cells by either Mengovirus or poliovirus causes the appearance of a new cytoplasmic RNA polymerase. The enzymes induced by the two viruses are quite similar. Both show a requirement for magnesium ions, are inhibited by manganese ions, require all four nucleoside triphosphates for maximal activity, and catalyze the incorporation of each of the nucleoside monophosphates into RNA. The two polymerases are found in particulate cytoplasmic structures and neither is sensitive to actinomycin, a compound which inhibits all normal RNA synthesis. A new cytoplasmic, virus-specific polymerase activity was originally sought because autoradiographic experiments had shown viral RNA synthesis to be an actinomycin-insensitive, cytoplasmic process. Since the polymerase activity which was found appeared in the cytoplasm of infected cells with approximately the kinetics of viral RNA synthesis and was insensitive to actinomycin, it was presumed to mediate viral RNA synthesis in the cytoplasm without the involvement of DNA. The present communication describes experiments which demonstrate that the bulk of the product of the in vitro reaction is poliovirus RNA and that a small proportion is double-stranded RNA. Experiments on the structural localization of the polymerase within the cytoplasm are also presented, and the mechanism of the reaction is discussed.

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Baltimore, David0000-0001-8723-8190
Additional Information:© 1964 National Academy of Sciences. Communicated by Harry Eagle, January 20, 1964. This work was carried out in the laboratory of Dr. J. E. Darnell, whose advice and assistance are gratefully acknowledged. I should also like to thank Drs. S. Penman and Y. Becker for their aid, and Mrs. J. Burmeister for her competent technical assistance. This work was supported by grant C-5789 from the U.S. Public Health Service and grant GB-513 from the National Science Foundation.
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U. S. Public Health Service grantC-5789
Issue or Number:3
Record Number:CaltechAUTHORS:20120815-100006123
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:33202
Deposited On:15 Aug 2012 20:18
Last Modified:09 Nov 2021 21:33

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