Biomaterial Database

Initiation of (-)-strand RNA synthesis catalyzed by the BMV RNA-dependent RNA polymerase: synthesis of oligonucleotides. 1996

J H Sun, and S Adkins, and G Faurote, and C C Kao

Department of Biology, Indiana University, Bloomington 47405, USA.

RNA replication, a process of fundamental importance for pathogenesis by many viruses, remains poorly understood at the mechanistic level because relatively few of the responsible enzymes have been purified and characterized biochemically. Partially purified RNA-dependent RNA polymerase (RdRp) from brome mosaic virus (BMV)-infected barley leaves is able to synthesize (-)-strand RNAs from input (+)-strand templates. In resolving RdRp products generated during (-)-strand BMV RNA synthesis, we found that an RNA of eight nucleotides was generated at approximately 10-fold molar excess to the full-length (-)-strand RNA. Production of the 8-mer was dependent upon and specific to BMV RNA templates. Furthermore, inhibitors of full-length (-)-strand RNA synthesis by RdRp also affected the production of the 8-mer. Analysis of the sequence of the 8-mer suggests that it is initiated at the authentic initiation site on the BMV RNA template, consistent with the possibility that the 8-mer is an abortive initiation product of RNA synthesis by RdRp in vitro. Addition of heparin or Mn2+ differentially affected production of the 8-mer and full-length (-)-strand RNA, as did some nucleotide changes near the site of RNA initiation. These studies further define the initiation process of (-)-strand RNA synthesis.

UI	MeSH Term	Description	Entries
D008345	Manganese	A trace element with atomic symbol Mn, atomic number 25, and atomic weight 54.94. It is concentrated in cell mitochondria, mostly in the pituitary gland, liver, pancreas, kidney, and bone, influences the synthesis of mucopolysaccharides, stimulates hepatic synthesis of cholesterol and fatty acids, and is a cofactor in many enzymes, including arginase and alkaline phosphatase in the liver. (From AMA Drug Evaluations Annual 1992, p2035)
D009843	Oligoribonucleotides	A group of ribonucleotides (up to 12) in which the phosphate residues of each ribonucleotide act as bridges in forming diester linkages between the ribose moieties.
D012313	RNA	A polynucleotide consisting essentially of chains with a repeating backbone of phosphate and ribose units to which nitrogenous bases are attached. RNA is unique among biological macromolecules in that it can encode genetic information, serve as an abundant structural component of cells, and also possesses catalytic activity. (Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	RNA, Non-Polyadenylated,Ribonucleic Acid,Gene Products, RNA,Non-Polyadenylated RNA,Acid, Ribonucleic,Non Polyadenylated RNA,RNA Gene Products,RNA, Non Polyadenylated
D012324	RNA-Dependent RNA Polymerase	An enzyme that catalyses RNA-template-directed extension of the 3'- end of an RNA strand by one nucleotide at a time, and can initiate a chain de novo. (Enzyme Nomenclature, 1992, p293)	Nucleoside-Triphosphate:RNA Nucleotidyltransferase (RNA-directed),RNA Replicase,RNA-Dependent RNA Replicase,RNA-Directed RNA Polymerase,RNA Dependent RNA Polymerase,RNA Dependent RNA Replicase,RNA Directed RNA Polymerase,RNA Polymerase, RNA-Dependent,RNA Polymerase, RNA-Directed,RNA Replicase, RNA-Dependent,Replicase, RNA,Replicase, RNA-Dependent RNA
D013698	Templates, Genetic	Macromolecular molds for the synthesis of complementary macromolecules, as in DNA REPLICATION; GENETIC TRANSCRIPTION of DNA to RNA, and GENETIC TRANSLATION of RNA into POLYPEPTIDES.	Genetic Template,Genetic Templates,Template, Genetic
D017795	Bromovirus	A genus of tripartite plant viruses in the family BROMOVIRIDAE. Transmission is by beetles. Brome mosaic virus is the type species.	Brome mosaic virus,Cowpea chlorotic mottle virus,Brome mosaic viruses