Poly(A) Polymerase Activity in Reovirus

AUTOR(ES)

Stoltzfus, C. M.

RESUMO

An enzymatic activity which synthesized oligo(A) in vitro was found in highly purified reovirus. The poly(A) polymerase activity was dependent on Mn2+ and utilized only ATP, whereas the virion-associated RNA polymerase required all four ribonucleoside triphosphates and Mg2+. Oligo(A) synthesis was demonstrated with complete virions and infectious subviral particles derived from virus by limited chymotrypsin digestion but not with cores, a product of extensive chymotrypsin digestion of virus. The enzymatic product and the oligo(A) from purified virions were isolated by binding to oligo(dT)-cellulose columns. Most of the in vitro product was similar in size and structure to the oligo(A) from purified virions by the criteria of gel electrophoresis, DEAE-cellulose chromatography, end-group analysis, and sensitivity to RNase. The evidence suggests that oligo(A) synthesis is mediated by the poly(A) polymerase during a late step in viral morphogenesis and may result from an alternative activity of the virion-associated transcriptase.

Documentos Relacionados

• Poly(A) Polymerase and Poly(G) Polymerase in Wheat Chloroplasts
• The enzyme that adds poly(A) to mRNAs is a classical poly(A) polymerase.
• Polyadenylation of maternal mRNA during oocyte maturation: poly(A) addition in vitro requires a regulated RNA binding activity and a poly(A) polymerase.
• Poly(A) polymerase contains multiple functional domains.
• Host factor Hfq of Escherichia coli stimulates elongation of poly(A) tails by poly(A) polymerase I