title: Salt-resistant association of simian virus 40 T antigen with simian virus 40 DNA in nucleoprotein complexes.
abstract: Treatment of nucleoprotein complexes (NPCs) from simian virus 40 (SV40)-infected TC7 cells with NaCl (1 or 2 M) or guanidine-hydrochloride (1 or 2 M) resulted in a significant fraction of T antigen still associated with SV40 (I) DNA. Immunoprecipitation of the salt-treated NPCs with SV40 anti-T serum indicated that T antigen is preferentially associated with SV40 (I) DNA rather than with SV40 (II) DNA. Treatment of the NPCs with 4 M guanidine-hydrochloride, however, resulted in a substantial decrease in the amount of SV40 (I) and (II) DNA associated with T antigen. As the temperature was increased to 37 degrees C during incubation of NPCs with NaCl or guanidine-hydrochloride, there was a decrease in the amount of SV40 (I) and (II) DNA immunoprecipitated with SV40 anti-T serum. In the absence of salt, temperature had no effect on the association of T antigen with the SV40 DNA in the NPCs. Treatment of NPCs from SV40 wildtype or tsA58-infected cells grown at the permissive temperature with 1 or 2 M NaCl indicated that tsA T antigen has the same sensitivities as wild-type T antigen to high salt treatment when bound to DNA in NPCs. Characterization of the proteins associated with SV40 (I) DNA after high salt treatment revealed that, in addition to T antigen, a certain amount of viral capsid proteins VP1 and VP3 remained associated with the DNA. Complexes containing SV40 (I) DNA had a sedimentation value of 53S after 1 M NaCl treatment and 43S after 2 M NaCl treatment.
mesh_terms: D000957:Antigens, Viral, Tumor; D002499:Centrifugation, Density Gradient; D004279:DNA, Viral / Q000032:analysis*; D003850:Deoxyribonuclease I; D003852:Deoxyribonucleoproteins / Q000032:analysis*; D004706:Endodeoxyribonucleases; D019791:Guanidine; D006146:Guanidines / Q000494:pharmacology; D011233:Precipitin Tests; D013539:Simian virus 40 / Q000032:analysis* / Q000276:immunology; D012965:Sodium Chloride / Q000494:pharmacology
chemical_list: D000957:Antigens, Viral, Tumor; D004279:DNA, Viral; D003852:Deoxyribonucleoproteins; D006146:Guanidines; D012965:Sodium Chloride; D004706:Endodeoxyribonucleases; D003850:Deoxyribonuclease I; D019791:Guanidine