AUTOGRAPHA-CALIFORNICA NUCLEAR POLYHEDROSIS-VIRUS - SUBCELLULAR-LOCALIZATION AND PROTEIN TRAFFICKING OF BV ODV-E26 TO INTRANUCLEAR MEMBRANES AND VIRAL ENVELOPES/

The Autographa californica nuclear polyhedrosis virus da26 gene codes for an envelope protein of both budded virus (BV) and occlusion derive d virus (ODV). Western blot and temporal analysis of infected cell ext racts detected a protein of 26 kDa by 4 h postinfection (p.i.). The am ount of protein increased by 16 h p.i. and remained at high levels thr oughout infection. By 36 h p.i. several additional immunoreactive prot eins were detected which migrated at approximate to 18 kDa and remaine d through 96 h p.i. Western blot analysis of purified virus envelope a nd nucleocapsid preparations revealed that both the 26- and 18-kDa pro teins are structural proteins of the envelope of BV and ODV. Immunoele ctron microscopy performed at a time when only the 26-kDa species of t he protein was present confirmed that the protein located to ODV envel ope. The protein was named BV/ODV-E26 to designate incorporation into viral progeny, envelope location, and apparent molecular weight. Studi es designed to follow localization of BV/ODV-E26 demonstrated that ear ly in infection, the protein was incorporated into cytoplasmic vesicle s and by 16 h p.i., BV/ODV-E26 was detected in the nucleus associated with virus-induced intranuclear microvesicles and ODV envelope. Coimmu noprecipitation and yeast two-hybrid assays showed that BV/ODV-E26 and FP25K were capable of interacting with each other to form a complex a nd coimmunoprecipitation assays indicated that cellular actin was a th ird component of this complex. Together, these data suggest that FP25K and cellular actin may participate in the regulation, or movement thr ough the cell, of baculovirus proteins and/or Virus nucleocapsids. (C) 1998 Academic Press.