Expression of v-rel in a replication competent virus: transformation and biochemical characterization.
The avian reticuloendotheliosis virus strain T (REV-T) transforms bone marrow cells and may cause phenotypic changes in fibroblasts. Both events are thought to result from expression of the v-rel oncoprotein, a member of the NF-kappa B family of transcription factors. Most REV stocks contain a cytopathic and immunosuppressive helper virus (REV-A) unrelated to standard avian retroviruses, and thus the degree to which v-rel expression alone contributes to the transformed phenotype in bone marrow cells and fibroblasts is complicated by helper virus expression. To gain a more accurate picture of how v-rel contributes to transformation, we have cloned the v-rel gene into a replication-competent avian retrovirus vector (RCAS) and have expressed it in both chick embryo fibroblasts (CEF) and bone marrow cells. Transfection of RCAS-rel into CEF readily produced a partially transformed phenotype, demonstrating that expression of the v-rel protein is sufficient for fibroblast transformation. The RCAS-rel virus also transformed bone marrow cells in vitro, but required culture conditions different from those normally required for transformation by REV-T. The v-rel protein expressed in transformed CEF was biochemically indistinguishable from that expressed in transformed bone marrow cells, being localized to the cytoplasm and the nucleus, and forming a complex with cellular proteins. We also demonstrate that the RCAS-rel-transformed hematopoietic cells exhibited a distinct differentiation phenotype.
Morrison
L E
LE
Department of Microbiology, SUNY, Stony Brook 11794.
Boehmelt
G
G
Beug
H
H
Enrietto
P J
PJ
D000818:Animals; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D002642:Chick Embryo; D002645:Chickens; D002999:Clone Cells; D005347:Fibroblasts / Q000502:physiology; D006412:Hematopoietic Stem Cells / Q000166:cytology; D016328:NF-kappa B / Q000235:genetics; D020572:Oncogene Proteins v-rel; D009857:Oncogenes; D011505:Protein-Tyrosine Kinases / Q000235:genetics*; D001356:Reticuloendotheliosis virus / Q000235:genetics* / Q000502:physiology; D015682:Retroviridae Proteins, Oncogenic / Q000235:genetics*; D014162:Transfection; D014779:Virus Replication
D016328:NF-kappa B; D020572:Oncogene Proteins v-rel; D015682:Retroviridae Proteins, Oncogenic; D011505:Protein-Tyrosine Kinases