tokens: Plasmid subclones of the hr1a - containing AcMNPV HindIII - N fragment were examined for their ability to replicate in virus - infected ( Spodoptera frugiperda ) Sf9 cells , and to stimulate transcription when linked in cis with a 39K gene promoter - beta - glucuronidase fusion and cotransfected into cells along with a plasmid ( ple - 1 ) containing the gene encoding the trans - acting factor IE - 1 .