Effect of methyltransferase inhibitors on the regulation of baculovirus protein synthesis

In the presence of the methyltransferase inhibitor 3-deazaadenosine (3DA-Ado) the production of infectious Autographa californica nuclear polyhedrosis virus (AcMNPV) in tissue culture was only slightly affected, while the synthesis of very late proteins (polyhedrin and p10) was abolished. The synthesis of the influenza virus proteins NS1 and HA, expressed under the polyhedrin promoter, was also abolished by 3DA-Ado. Furthermore, 3DA-Ado interfered with the shut-off of early and late AcMNPV proteins. Most of these results were also obtained with 5-azadeoxycytidine (5A-dCyt). In cells in which NS1 was produced abundantly, at least one specific AcMNPV protein was not synthesized. However, if the production of NS1 was inhibited by 3DA-Ado, or if HA was synthesized instead, this AcMNPV protein showed up normally.