Subcellular localization of terminase subunits expressed using recombinant baculoviruses. Sf9 insect cells were infected at MOI = 3 with recombinant baculoviruses expressing UL56, UL89, or FLAG-UL51, as indicated. Soluble cytoplasmic (C) and nuclear (N) extracts were prepared 48 h post infection and analyzed by immunoblot using antibodies specific to each protein as indicated. Cytoplasmic and nuclear fractions were separated on different gels; for ease of comparison lanes from each are displayed side-by-side. In some blots anti-UL89 antibody cross-reacted with a cellular protein that migrated more slowly than UL89 (e.g., in the UL51/UL56 cytoplasmic extract).