transactivate
[ tran-sak-tuh-veyt, -zak- ]
/ trænˈsæk təˈveɪt, -ˈzæk- /
verb (used with object), trans·ac·ti·vat·ed, trans·ac·ti·vat·ing.
to activate the replication of (a viral gene) through the presence of a gene at another locus, especially following a viral infection.