About Simian Virus 40 (SV40) Essay -- Immunology, Diseases

Simian virus 40 (SV40) is a monkey virus that was introduced into the human population by contaminated poliovaccines. The vaccines were produced in SV40 infected monkey cells between 1955 and 1963. The site of latent infection in humans is not known but the presence of SV40 in urine suggests the kidney as a possible site of latency. SV40 is a small DNA virus that is studied extensively because it is able to transform and immortalize multiple cell types (Ozer 2000, Saenz-Robles et al. 2001). Polyoma viruses infect mammals causing tumors and cancer. Similarly to polyoma viruses, SV40 contains a DNA that is associated with histones in a circular complex containing 20- 22 nucleosomes (Varshavsky et al., 1977). SV40 DNA is located in a 50 nm capsid which is composed of homopentameters of the major capsid protein, VP1 (43 kilo Daltons) associated with one of the minor structural proteins VP2 or VP3. Under physiological salt and pH conditions, VP1 alone remains disassociated, and at pH 5, it assembles into tubular structures. Between pH 4 and pH 7, VP2 allows the VP1 pentameters to assemble in spherical particles and incorporates VP1. Furthermore, the virus has an icosahedral symmetry and contains 72 pentameters (Liddington et al., 1991). Figure 1shows the proposed structure of SV40 DNA and the length of each region within the virus. The diagram highlights the arrangement of the early and late regions. Furthermore, it shows the clockwise and counter clockwise symmetry of the large T antigen (TAg), small T antigen (tag), and the major capsid proteins within the virus. Figure 1: diagram of the SV40 virus genome. In 1989, Fogleman et al. analyzed the uncoating and penetration of Simian virus (SV 40). It uses the ganglioside... ... Takahashi, Y., et al. â€Å"Analysis of Promoter binding by the E2F and pRB Families In Vivo: Distinct E2F Proteins Mediate Activation and Repression.† Genes 14 (2000): 804-816. Tà ¼rler, Hans, and Consuelo Salomon. "Simian Virus 40 as a Vector: Recombinant Viruses Expressing Individual Polyoma T Antigens." Virus research 54.2 (1998): 133-45. . Varshavsky, A.J., et al. â€Å"Compact form of SV40 Viral Minichromosome is Resistant to Nuclease: Possible Implications for Chromatin Structure.† Nucleic acids research 4 (1977): 3303-3325. Vilchez, R.A. â€Å"Association between Simian Virus 40 and non-Hodgkin Lymphoma.† Lancet 359 (2002): 817-823. Wang, Chih-Hung, et al. "Simian Virus 40 T Antigen Induces p53-Independent Apoptosis but does Not Suppress erbB2/neu Gene Expression in Immortalized Human Epithelial Cells." Cancer letters 137.1 (1999): 107-15.