title: Small tumor antigen of polyomaviruses: role in viral life cycle and cell transformation.
abstract: The regulatory proteins of polyomaviruses, including small and large T antigens, play important roles, not only in the viral life cycle but also in virus-induced cell transformation. Unlike many other tumor viruses, the transforming proteins of polyomaviruses have no cellular homologs but rather exert their effects mostly by interacting with cellular proteins that control fundamental processes in the regulation of cell proliferation and the cell cycle. Thus, they have proven to be valuable tools to identify specific signaling pathways involved in tumor progression. Elucidation of these pathways using polyomavirus transforming proteins as tools is critically important in understanding fundamental regulatory mechanisms and hence to develop effective therapeutic strategies against cancer. In this short review, we will focus on the structural and functional features of one polyomavirus transforming protein, that is, the small t-antigen of the human neurotropic JC virus (JCV) and the simian virus, SV40.
authors.affiliation: Department of Neuroscience and Center for Neurovirology, Temple University School of Medicine, Philadelphia, Pennsylvania 19122, USA.
authors.forename: Kamel
authors.initials: K
authors.lastname: Khalili
authors.forename: Ilker Kudret
authors.initials: IK
authors.lastname: Sariyer
authors.forename: Mahmut
authors.initials: M
authors.lastname: Safak
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000957:Antigens, Viral, Tumor / Q000235:genetics / Q000502:physiology*; D002472:Cell Transformation, Viral / Q000502:physiology*; D006801:Humans; D007577:JC Virus / Q000276:immunology / Q000502:physiology*; D018832:Molecular Chaperones / Q000502:physiology; D008969:Molecular Sequence Data; D011494:Protein Kinases / Q000378:metabolism; D017434:Protein Structure, Tertiary / Q000502:physiology; D016364:Reading Frames; D016196:S Phase / Q000502:physiology; D013539:Simian virus 40 / Q000276:immunology / Q000502:physiology*; D058570:TOR Serine-Threonine Kinases; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D000957:Antigens, Viral, Tumor; D018832:Molecular Chaperones; D016159:Tumor Suppressor Protein p53; D011494:Protein Kinases; C546842:MTOR protein, human; D058570:TOR Serine-Threonine Kinases