Recurrent isolation of poliovirus 3 strains with chimeric capsid protein Vp1 suggests a recombination hot-spot site in Vp1.
Five oral poliovirus vaccine (OPV) strains carrying an intertypic PV3/PV2 recombination in VP1 capsid protein were isolated during poliovirus surveillance. These five PV3 strains had altogether four diverse recombination crossover points near the 3' end of the VP1 coding region. The complete antigenic site IIIa was replaced by PV2-specific amino acids in four of the studied PV3 strains. Low overall number of nucleotide substitutions in VP1 indicated that the predicted replication time, "age", of the PV3 strains was short, 6 months or less. The nucleotide 472-T in the 5' non-coding region, associated to the attenuated phenotype of PV3/Sabin, was reverted to wild-type C in all studied PV3/PV2 recombinant strains. Three of the PV3 strains had at least a tripartite genome deduced from the partial 3D polymerase-coding region sequences. Our results suggest that there exists a PV3/PV2 recombination hot-spot site in the 3' partial region of the VP1 capsid protein and that the recombination may occur within weeks or a few months after the administration of OPV.
Blomqvist
Soile
S
National Institute for Health and Welfare (THL), Department of Infectious Disease Surveillance and Control, Intestinal Viruses Unit, P.O. Box 30, 00271 Helsinki, Finland. soile.blomqvist@thl.fi
Savolainen-Kopra
Carita
C
Paananen
Anja
A
El Bassioni
Laila
L
El Maamoon Nasr
Eman M
EM
Firstova
Larisa
L
Zamiatina
Natalia
N
Kutateladze
Tamar
T
Roivainen
Merja
M
D036022:Capsid Proteins / Q000235:genetics*; D006801:Humans; D008969:Molecular Sequence Data; D017955:Poliovirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D023321:Poliovirus Vaccines / Q000008:administration & dosage*; D011110:Polymorphism, Genetic; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D014613:Vaccines, Attenuated / Q000008:administration & dosage; D014774:Virulence
D036022:Capsid Proteins; D023321:Poliovirus Vaccines; D012367:RNA, Viral; C442540:VP1 protein, Poliovirus; D014613:Vaccines, Attenuated