Nucleoside and nucleotide inactivation of R17 coat protein: evidence for a transient covalent RNA-protein bond

R17 coat protein forms a specific complex with a 21-nucleotide RNA hairpin containing the initiation site for the phage replicase gene. The RNA binding activity of the protein is inhibited by prior incubation with 5-bromouridine (BrU). The inactivation occurs with pseudo-first-order kinetics, and th...

Full description

Saved in:
Bibliographic Details
Published in:Biochemistry (Easton) 1985-07, Vol.24 (15), p.4239-4244
Main Authors: Romaniuk, Paul J., Uhlenbeck, Olke C.
Format: Article
Language:English
Subjects:
Biological and medical sciences
Capsid - metabolism
Capsid Proteins
Chloromercuribenzoates - pharmacology
Coliphages - metabolism
Ethylmaleimide - pharmacology
Fundamental and applied biological sciences. Psychology
Kinetics
Microbiology
p-Chloromercuribenzoic Acid
Replicative cycle, interference, host-virus relations, pathogenicity, miscellaneous strains
Ribonucleosides - pharmacology
Ribonucleotides - pharmacology
RNA, Transfer - metabolism
RNA-Binding Proteins
Structure-Activity Relationship
Virology
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:R17 coat protein forms a specific complex with a 21-nucleotide RNA hairpin containing the initiation site for the phage replicase gene. The RNA binding activity of the protein is inhibited by prior incubation with 5-bromouridine (BrU). The inactivation occurs with pseudo-first-order kinetics, and the inactive protein is stable to dilution. RNA binding activity of the BrU-inactivated protein is restored upon incubation with dithiothreitol. Inactivation of coat protein by N-ethylmaleimide or p-(chloromercuri)-benzenesulfonate indicates that a cysteine residue is located near the RNA binding site. Since 5-bromodeoxyuridine does not inactivate coat protein, a specific binding event appears to be required before inactivation can occur. Surprisingly, unmodified cytidine nucleotides also inactivate coat protein, with a specificity similar to the modified analogues. These results are discussed with regard to the formation of a transient covalent RNA-protein bond.
ISSN:0006-2960
1520-4995
DOI:10.1021/bi00336a064