title: Friend strain of spleen focus-forming virus: a recombinant between mouse type C ecotropic viral sequences and sequences related to xenotropic virus.
abstract: The genome of the Friend strain of the spleen focus-forming virus (SFFV) has been analyzed by molecular hybridization. SFFV is composed of genetic sequences homologous to Friend type C helper virus (F-MuLV) and SFFV-specific sequences not present in F-MuLV. These SFFV-specific sequences are present in both the Friend and Rauscher strains of murine erythroleukemia virus. The SFFV-specific sequences are partially homologous to three separate strains of mouse xenotropic virus but not to several cloned mouse ecotropic viruses. Thus, the Friend strain of SFFV appears to be a recombinant between a portion of the F-MuLV genome and RNA sequences that are highly related to murine xenotropic viruses. The implications of the acquisition of the xenotropic virus-related sequences are discussed in relation to the leukemogenicity of SFFV, and a model for the pathogenicity of other murine leukemia-inducing viruses is proposed.
mesh_terms: D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002999:Clone Cells; D005622:Friend murine leukemia virus / Q000032:analysis* / Q000254:growth & development / Q000472:pathogenicity; D006378:Helper Viruses / Q000032:analysis / Q000254:growth & development; D009052:Leukemia Virus, Murine / Q000032:analysis / Q000254:growth & development; D051379:Mice; D008970:Molecular Weight; D009690:Nucleic Acid Conformation; D009693:Nucleic Acid Hybridization; D012367:RNA, Viral / Q000032:analysis*; D051381:Rats; D011995:Recombination, Genetic; D012190:Retroviridae / Q000032:analysis / Q000254:growth & development; D014779:Virus Replication
chemical_list: D012367:RNA, Viral