Functional complementation of nuclear targeting-defective mutants of simian virus 40 structural proteins.

摘要: Structural proteins of simian virus 40 (SV40), Vp2 and Vp3 (Vp2/3) Vp1, carry individual nuclear targeting signals, Vp3(198-206) (Vp2(316-324) Vp1(1-8), respectively, which are encoded in different reading frames an overlapping region the genome. How signals coordinate during virion morphogenesis was examined by using SV40 variants there is only one structural gene for Vp1 or Vp2/3, targeting-defective mutants thereof, Vp2/3(202T) delta N5, nonoverlapping genes Vp2/3 separated, mutant derivatives carrying either both mutations. Nuclear assessed immunocytochemically following microinjection variant DNAs. When with defects were expressed individually, localized mostly to cytoplasm. However, when coexpressed same cell along wild-type protein effectively targeted nucleus. Likewise, N5 transported into nucleus cells. These results suggest that while have independent additional such as those defining protein-protein interactions, play a concerted role localization proteins.