Previous Article | Next Article ![]()
Journal of Virology, July 2000, p. 5939-5948, Vol. 74, No. 13
Department of Biochemistry and Institute for
Molecular Virology, The College of Agricultural and Life Sciences, and
The Graduate School, University of Wisconsin-Madison, Madison,
Wisconsin 53706,1 and Department of
Microbiology, University of Minnesota Medical School, Minneapolis,
Minnesota 554552
Received 14 December 1999/Accepted 5 April 2000
Reovirus nonstructural protein
0022-538X/00/$04.00+0
Copyright © 2000, American Society for Microbiology. All rights reserved.
Reovirus Protein
NS Binds in Multiple Copies to
Single-Stranded RNA and Shares Properties with Single-Stranded DNA
Binding Proteins
NS interacts with reovirus
plus-strand RNAs in infected cells, but little is known about the nature of those interactions or their roles in viral replication. In
this study, a recombinant form of
NS was analyzed for in vitro binding to nucleic acids using gel mobility shift assays. Multiple units of
NS bound to single-stranded RNA molecules with
positive cooperativity and with each unit covering about 25 nucleotides at saturation. The
NS protein did not bind preferentially to reovirus RNA over nonreovirus RNA in competition experiments but did
bind preferentially to single-stranded over double-stranded nucleic
acids and with a slight preference for RNA over DNA. In addition,
NS
bound to single-stranded RNA to which a 19-base DNA
oligonucleotide was hybridized at either end or near the middle. When
present in saturative amounts,
NS displaced this
oligonucleotide from the partial duplex. The strand displacement
activity did not require ATP hydrolysis and was inhibited by
MgCl2, distinguishing it from a classical ATP-dependent
helicase. These properties of
NS are similar to those of
single-stranded DNA binding proteins that are known to
participate in genomic DNA replication, suggesting a related role
for
NS in replication of the reovirus RNA genome.
*
Corresponding author. Mailing address: Institute for
Molecular Virology, University of Wisconsin-Madison, 1525 Linden Dr., Madison, WI 53706. Phone: (608) 262-1536. Fax: (608) 262-7414. E-mail:
mlnibert{at}facstaff.wisc.edu.
This article has been cited by other articles:
| J. Bacteriol. | Mol. Cell. Biol. | Microbiol. Mol. Biol. Rev. |
|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|