%0 Journal Article %A Tsfasman, T. M. %A Markushin, S. G. %A Akopova, I. I. %A Ghendon, Y. Z. %T Molecular mechanisms of reversion to the ts+ (non-temperature-sensitive) phenotype of influenza A cold-adapted (ca) virus strains %D 2007 %J Journal of General Virology, %V 88 %N 10 %P 2724-2729 %@ 1465-2099 %R https://doi.org/10.1099/vir.0.83014-0 %I Microbiology Society, %X A ts+ ca− (non-temperature-sensitive, non-cold-adapted) revertant of the A/Leningrad/134/47/57 ca strain influenza virus [A/Leningrad/134/47/ts+18/1957(H2N2)], obtained in our previous study, lost phenotypic manifestation of ts mutations by the PB2, NP and NS genes, although, according to sequencing data, it acquired only two true reversions of a mutation in the PB2 and PB1 genes. Direct sequencing showed the appearance of 27 additional mutations (13 coding) in the genes encoding the PB2, PB1, PA, NP, M and NS proteins of the revertant, along with the above-mentioned two true reversions. We conjecture that some of these mutations suppressed phenotypic manifestation of ts mutations in the NS and NP genes. %U https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.83014-0