title: Expression of the small T antigen of Lymphotropic Papovavirus is sufficient to transform primary mouse embryo fibroblasts.
abstract: Polyomaviruses induce cell proliferation and transformation through different oncoproteins encoded within the early region (ER): large T antigen (LT), small T antigen (sT) and, in some cases, additional components. Each virus utilizes different mechanisms to achieve transformation. For instance, the LTs of Simian virus 40 (SV40), BK and/or JC virus can induce transformation; but Merkel Cell Polyomavirus (MCPyV) requires expression of sT. Lymphotropic Papovavirus (LPV) is closely related to Human Polyomavirus 9 (HuPyV9) and, under similar conditions, mice expressing LPV.ER exhibit higher rates of tumor formation than mice expressing SV40.ER. We have investigated the contributions of individual LPV.ER components to cell transformation. In contrast to SV40, LPV.ER transforms mouse embryonic fibroblasts (MEFs), but expression of LPV LT is insufficient to transform MEFs. Furthermore, LPV sT induces immortalization and transformation of MEFs. Thus, in the case of LPV, sT is the main mediator of oncogenesis.
authors.affiliation: Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
authors.forename: Tushar
authors.initials: T
authors.lastname: Gupta
authors.affiliation: Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA.
authors.forename: Maria Teresa Sáenz
authors.initials: MT
authors.lastname: Robles
authors.affiliation: Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-4263, USA.
authors.forename: Rachel M
authors.initials: RM
authors.lastname: Schowalter
authors.affiliation: Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892-4263, USA.
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Buck
authors.affiliation: Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, USA. Electronic address: pipas@pitt.edu.
authors.forename: James M
authors.initials: JM
authors.lastname: Pipas
mesh_terms: D000818:Animals; D000957:Antigens, Viral, Tumor / Q000096:biosynthesis / Q000276:immunology*; D002471:Cell Transformation, Neoplastic / Q000473:pathology*; D002478:Cells, Cultured; D005347:Fibroblasts; D051379:Mice; D011120:Polyomavirus / Q000276:immunology*; D050720:Retinoblastoma-Like Protein p107 / Q000378:metabolism; D050717:Retinoblastoma-Like Protein p130 / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000378:metabolism
chemical_list: D000957:Antigens, Viral, Tumor; C489485:Rbl1 protein, mouse; C493838:Rbl2 protein, mouse; D050720:Retinoblastoma-Like Protein p107; D050717:Retinoblastoma-Like Protein p130; D016159:Tumor Suppressor Protein p53
keywords: LPV; Polyomavirus; SV40; Transformation; sT