May 21, 1992 - Biochemistry. Amplifiable messenger RNA. (exponential RNA synthesis/QIJ replicase/recombinant RNA/celI-free protein synthesis/biologically ...
Proc. Natl. Acad. Sci. USA Vol. 89, pp. 11769-11773, December 1992
Biochemistry
Amplifiable messenger RNA (exponential RNA synthesis/QIJ replicase/recombinant RNA/celI-free protein synthesis/biologically active chloramphenicol
acetyltransferase)
YING Wu, DAVID YONG ZHANG, AND FRED RUSSELL KRAMER Department of Molecular Genetics, Public Health Research Institute, 455 First Avenue, New York, NY 10016
Communicated by Leslie E. Orgel, August 24, 1992 (receivedfor review May 21, 1992)
RNA molecules were prepared that consisted ABSTRACT of an mRNA encoding chlorampheniol acetyltransferase embedded within the sequence of midivariant RNA, which is a template for the RNA-directed RNA polymerase Q13 replicase. These recombinant RNAs were shown to be bifunctional: they are amplified exponentially by incubation with QO replicase, and the replicated RNA serves as template for the cell-free synthesis of enzymatically active chloramphenicol acetyltransferase. The availability of amplifiable mRNAs will enable relatively large amounts of protein to be synthesized in vitro.
QP replicase is an extraordinary RNA polymerase because it catalyzes the synthesis of a very large number of product strands from a small number oftemplate strands. Million-fold increases occur in
