Peptide display on live MS2 phage: restrictions at the RNA genome level.
The potential of the RNA phage MS2 to accommodate extra amino acids in its major coat protein has been examined. Accordingly, a pentapeptide was encoded in the genome as an N-terminal extension. In the MS2 crystal structure, this part of the coat protein forms a loop that extends from the outer surface of the icosahedral virion. At the RNA level, the insert forms a large loop at the top of an existing hairpin. This study shows that it is possible to maintain inserts in the coat protein of live phages. However, not all inserts were genetically stable. Some suffer deletions, while others underwent adaptation by base substitutions. Whether or not an insert is stable appears to be determined by the choice of the nucleic acid sequence used to encode the extra peptide. This effect was not caused by differential translation, because coat-protein synthesis was equal in wild-type and mutants. We conclude that the stability of the insert depends on the structure of the large RNA hairpin loop, as demonstrated by the fact that a single substitution can convert an unstable loop into a stable one.
van Meerten
Dico
D
Leiden Institute of Chemistry, Department of Biochemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands1.
Olsthoorn
Rene C L
RCL
Leiden Institute of Chemistry, Department of Biochemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands1.
van Duin
Jan
J
Leiden Institute of Chemistry, Department of Biochemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands1.
Verhaert
Raymond M D
RMD
Leiden Institute of Chemistry, Department of Biochemistry, Gorlaeus Laboratories, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands1.
D001483:Base Sequence; D002213:Capsid / Q000235:genetics* / Q000378:metabolism; D004251:DNA Transposable Elements; D017909:Levivirus / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D009690:Nucleic Acid Conformation; D010455:Peptides / Q000235:genetics / Q000378:metabolism; D012367:RNA, Viral / Q000737:chemistry; D011994:Recombinant Proteins / Q000235:genetics
D004251:DNA Transposable Elements; D010455:Peptides; D012367:RNA, Viral; D011994:Recombinant Proteins