Induction of syncytia by Moloney murine leukemia virus in myoblasts defective in differentiation.
fu-1 cells, a nonfusing variant of the L8 line of rat myoblasts, form syncytia upon infection with murine leukemia virus (MuLV) or upon cocultivation with MuLV-infected cells; L8 cells do not form these syncytia, but do fuse into multinucleate myotubes. Syncytia of fu-1 cells form within 1 h after infection. The number of syncytia formed is proportional to the multiplicity of virus within a range of 4 to 16 and is maximum when the cell density is subconfluent. When either XC or fu-1 cells are productively infected with MuLV, they become resistant to syncytia formation by passage 3. The rapid formation of syncytia in fu-1 cells was found amenable for selection of temperature-sensitive mutants of MuLV and for screening additional variants of the L8 line.
D000818:Animals; D002454:Cell Differentiation; D002459:Cell Fusion; D002460:Cell Line; D002478:Cells, Cultured / Q000502:physiology*; D008979:Moloney murine leukemia virus / Q000254:growth & development*; D009132:Muscles / Q000196:embryology; D009154:Mutation; D051381:Rats; D014779:Virus Replication