Properties of the DNA-binding domain of the simian virus 40 large T antigen.
T antigen (Tag) from simian virus 40 binds specifically to two distinct sites in the viral origin of replication and to single-stranded DNA. Analysis of the protein domain responsible for these activities revealed the following. (i) The C-terminal boundary of the origin-specific and single-strand-specific DNA-binding domain is at or near amino acid 246; furthermore, the maximum of these DNA-binding activities coincides with a narrow C-terminal boundary, spanning 4 amino acids (246 to 249) and declines sharply in proteins with C termini which differ by a few (4 to 10) amino acids; (ii) a polypeptide spanning residues 132 to 246 of Tag is an independent domain responsible for origin-specific DNA binding and presumably for single-stranded DNA binding; and (iii) a comparison of identical N-terminal fragments of Tag purified from mammalian and bacterial cells revealed differential specificity and levels of activity between the two sources of protein. A role for posttranslational modification (phosphorylation) in controlling the DNA-binding activity of Tag is discussed.
McVey
D
D
Cold Spring Harbor Laboratory, New York 11724.
Strauss
M
M
Gluzman
Y
Y
D000595:Amino Acid Sequence; D000952:Antigens, Polyomavirus Transforming; D001483:Base Sequence; D002872:Chromosome Deletion; D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000235:genetics / Q000378:metabolism; D004279:DNA, Viral / Q000235:genetics / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D005800:Genes, Fungal; D006367:HeLa Cells / Q000378:metabolism; D006801:Humans; D008969:Molecular Sequence Data; D009692:Nucleic Acid Heteroduplexes / Q000235:genetics / Q000378:metabolism*; D015345:Oligonucleotide Probes / Q000138:chemical synthesis; D010957:Plasmids; D011995:Recombination, Genetic; D013539:Simian virus 40 / Q000235:genetics / Q000276:immunology*; D013698:Templates, Genetic
D000952:Antigens, Polyomavirus Transforming; D004277:DNA, Single-Stranded; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D009692:Nucleic Acid Heteroduplexes; D015345:Oligonucleotide Probes