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. 1991 Apr;65(4):2098–2101. doi: 10.1128/jvi.65.4.2098-2101.1991

Protein phosphatase 2A dephosphorylates simian virus 40 large T antigen specifically at residues involved in regulation of DNA-binding activity.

K H Scheidtmann 1, D M Virshup 1, T J Kelly 1
PMCID: PMC240073  PMID: 1848320

Abstract

Treatment of purified simian virus 40 large T antigen (LT) with protein phosphatase 2A stimulates LT-dependent DNA unwinding and replication (D. M. Virshup, M. G. Kauffman, and T. J. Kelly, EMBO J. 8: 3891-3898, 1989). The specificity of the catalytic subunit of protein phosphatase 2A toward LT was investigated by two-dimensional peptide mapping. Increasing amounts of phosphatase sequentially removed the phosphates from serine residues 120, 123, 677, and perhaps 679, residues which have been implicated in regulating the DNA-binding activity of LT.

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Selected References

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