Previous Article | Next Article ![]()
Journal of Virology, September 1999, p. 7467-7473, Vol. 73, No. 9
Laboratory of Pediatric and Respiratory Viral
Diseases, Division of Viral Products, Office of Vaccines Research
and Review, Center for Biologics Evaluation and Research, Food and
Drug Administration, Bethesda, Maryland 20892
Received 16 February 1999/Accepted 25 May 1999
To characterize the sites and nature of binding of influenza A
virus matrix protein (M1) to ribonucleoprotein (RNP), M1 of A/WSN/33
was altered by deletion or site-directed mutagenesis, expressed in
vitro, and allowed to attach to RNP under a variety of conditions.
Approximately 70% of the wild-type (Wt) M1 bound to RNP at pH 7.0, but
less than 5% of M1 associated with RNP at pH 5.0. Increasing the
concentration of NaCl reduced M1 binding, but even at a high salt
concentration (0.6 M NaCl), approximately 20% of the input M1 was
capable of binding to RNP. Mutations altering potential M1 RNA-binding
regions (basic amino acids 101RKLKR105 and the zinc finger motif at
amino acids 148 to 162) had varied effect: mutations of amino acids 101 to 105 reduced RNP binding compared to the Wt M1, but mutations of zinc
finger motif did not. Treatment of RNP with RNase reduced M1 binding by
approximately half, but even M1 mutants lacking RNA-binding regions had
residual binding to RNase-treated RNP provided that the N-terminal 76 amino acids of M1 (containing two hydrophobic domains) were intact. Addition of detergent to the reaction mixture further reduced binding
related to the N-terminal 76 amino acids and showed the greatest effect
for mutations affecting the RNA-binding regions of basic amino acids.
The data suggest that M1 interacts with both the RNA and protein
components of RNP in assembly and disassembly of influenza A viruses.
0022-538X/99/$04.00+0
Association of Influenza Virus Matrix Protein
with Ribonucleoproteins
*
Corresponding author. Mailing address: Bldg. 29A, Rm.
1D22, 8800 Rockville Pike, Bethesda, MD 20892. Phone: (301) 827-1906. Fax: (301) 402-5128. E-mail: yez{at}cber.fda.gov.
This article has been cited by other articles:
| J. Bacteriol. | Mol. Cell. Biol. | Microbiol. Mol. Biol. Rev. |
|---|
| Clin. Vaccine Immunol. | ALL ASM JOURNALS |
|---|