comparison of nucleotide sequences of the transcriptional control regions among the mutants and the wild type showed that pm526 is a parent virus , from which all the other mutants had evolved , and that the evolutionary changes of the plaque size , from minute to small to large , were due to duplications of a certain segment containing the adenovirus e1a enhancer core or the simian virus 40 enhancer core found in the bkv 68-base-pair element .
C1158770
transcriptional control
C1709313
e1a