title: Molecular cloning of Friend mink cell focus-inducing virus: identification of mink cell focus-inducing virus-like messages in normal and transformed cells.
abstract: Friend mink cell focus-inducing virus (Fr-MCF) is a leukemogenic murine retrovirus that was isolated from a leukemic NIH Swiss mouse. We molecularly cloned the genome of this virus into pBR322. Restriction enzyme mapping of this cloned Fr-MCF DNA revealed a 1.0-kilobase-pair region in the envelope gene which differs from the restriction map of the Friend ecotropic virus (Friend murine leukemia virus). A 400-base-pair Fr-MCF envelope gene fragment was subcloned from this region and designated pLEK. Probes made with pLEK hybridize to Fr-MCF DNA but do not hybridize to either Friend or amphotropic murine leukemia virus DNA. Polyadenylic acid-selected RNA was prepared from the hematopoietic tissues of normal NIH Swiss mice, Fr-MCF-infected erythroleukemia cells (TP-1), and uninfected chemically transformed T lymphocytes (RB-1). The pLEK probe identified 34S and 22S messages in the TP-1 cells and in the normal hematopoietic tissues. RB-1 cells contain 32S and 26S messages that hybridize to pLEK. However, the pLEK-like RNAs found in the normal hematopoietic tissues and in the RB-1 cells were 400-fold less abundant than the RNAs found in the TP-1 cells.
mesh_terms: D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D005622:Friend murine leukemia virus / Q000235:genetics; D005814:Genes, Viral; D009052:Leukemia Virus, Murine / Q000235:genetics*; D004915:Leukemia, Erythroblastic, Acute; D008907:Mink; D012333:RNA, Messenger / Q000032:analysis*; D012367:RNA, Viral / Q000032:analysis; D013601:T-Lymphocytes; D014759:Viral Envelope Proteins / Q000235:genetics
chemical_list: D012333:RNA, Messenger; D012367:RNA, Viral; D014759:Viral Envelope Proteins; D004262:DNA Restriction Enzymes