TY - JOUR T1 - Inhibition of Synthesis of Murine Leukemia Virus in Cultured Cells by Polyribonucleotides and Their 2'-<em>O</em>-Alkyl Derivatives JF - Molecular Pharmacology JO - Mol Pharmacol SP - 234 LP - 241 VL - 12 IS - 2 AU - S. K. ARYA AU - WILLIAM A. CARTER AU - JAMES L. ALDERFER AU - PAUL O. P. TS’O Y1 - 1976/03/01 UR - http://molpharm.aspetjournals.org/content/12/2/234.abstract N2 - Poly(adenylic acid) [poly(A)], poly(inosinic acid) [poly(I)], poly(uridylic acid) [poly(U)], and poly(cytidylic acid) [poly(C)]inhibit the synthesis of Moloney murine leukemia virus in cultured JLS-V9 cells. The potency of inhibition depends on the base composition; poly(I) is more potent than poly(A) and poly(U), and poly(C) yields only a marginal relative inhibition. 2'-O-Alkyl polynucleotides show an enhanced inhibitory potency relative to the parent polynucleotides, and this enhancement is more marked for pyrimidine than for purine polynucleotides. These polynucleotides do not affect the population growth rates of normal cells; thus inhibition of virus synthesis apparently is not due to any cytotoxicity of polynucleotides for normal cells. The following order of inhibitory potency is observed: poly(I) &gt; poly(A) &gt; poly(U) &gt; poly(C); poly(2'-O-methylmosinic acid) [poly(Im)] &gt; poly(2'-O-methyl-uridylic acid) [poly(Um)] &gt; poly(2'-O-ethyl-adenylic acid) [poly(Ae)] &gt; poly(Am) [unknown] poly(2'-O-methyl-cytidylic acid) [poly(Cm)]; and poly(Im) &gt; poly(I), poly(Am) &gt; poly(A), poly(Um) &gt; poly(U), poly(Cm) &gt; poly(C). ACKNOWLEDGMENTS We thank Mr. L. R. Davis for technical assistance, and Dr. R. J. Eckner for providing the leukemic spleen extract. ER -