Packaging motor with helicase and translocase activities. Part of the packaging complex that packages the viral RNA segments, replicate them into a double-stranded form and transcribe them. is one of the structural proteins of the polyhedral procapsid, which is responsible for genomic replication and transcription. Displays single-stranded RNA-stimulated NTPase activity. a ribonucleoside 5'-triphosphate + H2O = a ribonucleoside 5'-diphosphate + H(+) + phosphate Homohexamer. Part of the packaging complex composed of RDRP, P4 and P7. Capsid protein found in 72 copies. Prior to RNA packaging, localizes on the outer procapsid surface at the 12 potential RNA portal sites.