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E V Pilipenko

Publications and source records attributed to E V Pilipenko.

27 records · Page 2Linked to original sources

Gross rearrangements within the 5'-untranslated region of the picornaviral genomes.

An analysis of reported nucleotide sequences revealed several cases of gross rearrangements in the 5'-untranslated region (5-UTR) of picornaviral genomes. A large (greater than 100 nt) duplication was discovered in a downstream region of poliovirus 5-UTR involved in the translational control. Properties of the poliovirus mutants with large deletions [Kuge and Nomoto (1987) J. Virol. 61, 1478-1487] show that a single copy of the appropriate repeating unit is compatible with a wild type phenotype of the virus. In contrast to poliovirus and another enterovirus genomes, human rhinovirus RNAs contain only a single copy of this repeating unit. Another similarly large repeat was found in an upstream segment of the bovine enterovirus 5-UTR. A comparison of the primary and secondary structures of cardio- and aphthovirus 5-UTRs demonstrated the existence of a large (ca. 250 nucleotides) insertion/deletion in a region preceding the poly(C) tract. The two latter rearrangements appear to involve elements of the viral genome replication machinery. Possible origin as well as evolutionary and functional implications of these structural peculiarities are discussed.

Aphthovirus↗

Conservation of the secondary structure elements of the 5'-untranslated region of cardio- and aphthovirus RNAs.

An analysis of published nucleotide sequences of the 5'-untranslated region (5'-UTR) of 7 cardioviruses and 3 aphthoviruses has allowed us to derive a consensus secondary structure model that differs from that previously proposed for the 5'-UTR of entero- and rhinoviruses, though all these viruses belong to the same family, Picornaviridae. The theoretical model derived here was experimentally supported by investigating the accessibility of encephalomyocarditis virus RNA to modifications with dimethyl sulfate and its susceptibility to S1 and cobra venom nucleases. The possible involvement of the 5"-UTR secondary structure domains in the translational control is briefly discussed.

Animals↗

Conserved structural domains in the 5'-untranslated region of picornaviral genomes: an analysis of the segment controlling translation and neurovirulence.

A model of secondary structure common for the central part (ca. 400 nucleotides) of the 5'-untranslated regions (5'-UTR) of all the so far sequenced genomes of polioviruses, coxsackieviruses, and rhinoviruses was derived on the basis of evolutionary and thermodynamic considerations. According to the model, this part of the genome comprises three domains, which appear to be involved, at least in the poliovirus genome, in the control of viral neurovirulence and in vitro translation. Some salient features of this model were supported by investigating RNAs of five poliovirus and one coxsackievirus strains with respect to their accessibility to modifications with dimethyl sulfate and sensitivity to single-strand- and double-strand-specific nucleases. In contrast to the previous suggestion, no major changes in the conformation of the Sabin vaccine poliovirus type 3 5'-UTR due to the transition in position 472 were observed. The biological relevance of the conserved primary and secondary structure elements in the picornaviral 5'-UTRs is discussed.

Base Sequence↗

[Probable compact structure of a cis-active translation element in the 5'-untranslated region of the enterovirus and rhinovirus genome].

A previously proposed consensus secondary structure model of the internal portion of the 5'-untranslated region of the enterovirus and rhinovirus genomes encompassing the cis-acting translational control element was extended and detailed on the basis of comparative sequence data and biochemical analysis. Using this model as a reference, numerous pairs of apparently single-stranded noncontiguous nucleotide stretches with a potential to form inter-domain tertiary bonds were shown to be conserved among the respective segments of all the known enterovirus and rhinovirus RNAs. It is suggested that at least some of these inter-domain bonds may actually exist, resulting in a compact, quasi-globular, perhaps "two-lobe" folding of the translational control element. Such an organization should have important functional implications.

Base Sequence↗

[The critical significance of a conserved single-stranded interdomain linker in the 5'-untranslated region of poliovirus RNA].

Translation of polioviral RNA is initiated by interaction of a small ribosomal subunit with internal segments of the 5'-untranslated region (5'UTR). Several mutations were constructed within 5'UTR segment 425-449. All of them (including a single C444-->U replacement) inhibited in vitro translation, which decreased about 10-fold. Two mutant constructs, pPV12-05 (C444-->U) and pPV12K (containing also an AAUU insert between positions 441 and 442) produced plaques on monolayers of susceptible cells. All the viruses isolated from these plaques exhibited a reversion at position 444; the template activities of the revertant RNAs were restored completely or significantly. The results show the importance of the relevant 5'UTR segment for the initiation of polioviral RNA translation.

Base Sequence↗