Effect of inhibitors of proteases and glycosidases on functional lability of newly synthesized hemagglutinin-neuraminidase glycoprotein in avirulent NDV strain-infected cells.
Inhibition of either glycosylation or the protein synthesis leads to sharp drop of hemagglutinating (HA) and neuraminidase (Nase) activities in Newcastle disease virus (NDV)-infected cells. The drop can be prevented by tosyl-lysyl-chloromethyl-ketone, an inhibitor of trypsin-like proteases, or D-galactonolactone, an inhibitor of glycosidases, if added together with cycloheximide. Tosyl-lysyl-chloromethyl-ketone when added alone increases the level of both the HA and Nase activities as compared with non-treated virus-infected cells. It has been suggested that the actual level of the HA and Nase activities in the virus-infected cells is a result of dynamic equilibrium between the synthesis and post-translational functional maturation of the hemagglutinin-neuraminidase (HN) molecules, on the one hand, and the protease and glycosidase-mediated functional inactivation, on the other.
Lipkind
M
M
Kimron Veterinary Institute, Beit Dagan, Israel.
Shihmanter
E
E
D000818:Animals; D002478:Cells, Cultured; D002642:Chick Embryo; D003513:Cycloheximide / Q000494:pharmacology; D003847:Deoxyglucose / Q000494:pharmacology; D006026:Glycoside Hydrolases / Q000037:antagonists & inhibitors*; D006031:Glycosylation; D015707:HN Protein; D006389:Hemagglutinins, Viral / Q000378:metabolism*; D009439:Neuraminidase / Q000378:metabolism; D009522:Newcastle disease virus / Q000187:drug effects / Q000378:metabolism*; D011480:Protease Inhibitors / Q000494:pharmacology*; D013400:Sugar Acids / Q000494:pharmacology; D014107:Tosyllysine Chloromethyl Ketone / Q000494:pharmacology; D014759:Viral Envelope Proteins / Q000378:metabolism*
D015707:HN Protein; D006389:Hemagglutinins, Viral; D011480:Protease Inhibitors; D013400:Sugar Acids; D014759:Viral Envelope Proteins; D014107:Tosyllysine Chloromethyl Ketone; C007813:galactonolactone; D003513:Cycloheximide; D003847:Deoxyglucose; D006026:Glycoside Hydrolases; D009439:Neuraminidase