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. 1994 Dec 20;91(26):12398–12402. doi: 10.1073/pnas.91.26.12398

Binding of the human papillomavirus E1 origin-recognition protein is regulated through complex formation with the E2 enhancer-binding protein.

M G Frattini 1, L A Laimins 1
PMCID: PMC45445  PMID: 7809048

Abstract

The papillomavirus E1 and E2 proteins form heteromeric complexes and individually bind specific sequences within the viral origin of replication. The mechanism by which these proteins are recruited to the origin and the role of the E1/E2 complex in replication remain undefined. To examine the interplay of these replication proteins, we have analyzed the binding of human papillomavirus (HPV) type 31b E1 and E2 proteins to the origin of replication. Binding of E1 to the origin was increased by E2 proteins and required the presence of E2 binding sites. This increase was due to the formation of E1/E2 complexes which preferentially bound E2-responsive sequences, and the magnitude was determined by the relative affinity of the E2 binding sites. While the E1 protein alone bound an A/T-rich sequence at the HPV-31b origin with low affinity, complexes of E1 and E2 bound instead to E2 binding sites with high affinity. The E1/E2 complex bound a similar sequence as E2 homodimers, but only E2 homodimer binding induced a significant increase in hypersensitivity as indicated by DNase I footprinting. In the presence of excess E1, E1 proteins bound both the A/T-rich sequence and E2 binding sites through complex formation with E2. In E2 excess, E1/E2 complexes preferentially formed, and binding was specific for E2 sites. Therefore, changes in the relative amounts of E1 and E2 proteins can dramatically alter the pattern of binding of viral replication factors to the origin. These observations suggest a model whereby modulation of the relative levels of E1 and E2 during the viral life cycle may alter the pattern of origin binding and possibly episomal copy number.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Androphy E. J., Lowy D. R., Schiller J. T. Bovine papillomavirus E2 trans-activating gene product binds to specific sites in papillomavirus DNA. Nature. 1987 Jan 1;325(6099):70–73. doi: 10.1038/325070a0. [DOI] [PubMed] [Google Scholar]
  2. Bedell M. A., Hudson J. B., Golub T. R., Turyk M. E., Hosken M., Wilbanks G. D., Laimins L. A. Amplification of human papillomavirus genomes in vitro is dependent on epithelial differentiation. J Virol. 1991 May;65(5):2254–2260. doi: 10.1128/jvi.65.5.2254-2260.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Blitz I. L., Laimins L. A. The 68-kilodalton E1 protein of bovine papillomavirus is a DNA binding phosphoprotein which associates with the E2 transcriptional activator in vitro. J Virol. 1991 Feb;65(2):649–656. doi: 10.1128/jvi.65.2.649-656.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Cheng L. Z., Workman J. L., Kingston R. E., Kelly T. J. Regulation of DNA replication in vitro by the transcriptional activation domain of GAL4-VP16. Proc Natl Acad Sci U S A. 1992 Jan 15;89(2):589–593. doi: 10.1073/pnas.89.2.589. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Chiang C. M., Ustav M., Stenlund A., Ho T. F., Broker T. R., Chow L. T. Viral E1 and E2 proteins support replication of homologous and heterologous papillomaviral origins. Proc Natl Acad Sci U S A. 1992 Jul 1;89(13):5799–5803. doi: 10.1073/pnas.89.13.5799. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. DePamphilis M. L. Transcriptional elements as components of eukaryotic origins of DNA replication. Cell. 1988 Mar 11;52(5):635–638. doi: 10.1016/0092-8674(88)90398-4. [DOI] [PubMed] [Google Scholar]
  7. Del Vecchio A. M., Romanczuk H., Howley P. M., Baker C. C. Transient replication of human papillomavirus DNAs. J Virol. 1992 Oct;66(10):5949–5958. doi: 10.1128/jvi.66.10.5949-5958.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Frattini M. G., Laimins L. A. The role of the E1 and E2 proteins in the replication of human papillomavirus type 31b. Virology. 1994 Nov 1;204(2):799–804. doi: 10.1006/viro.1994.1596. [DOI] [PubMed] [Google Scholar]
  9. Guo Z. S., DePamphilis M. L. Specific transcription factors stimulate simian virus 40 and polyomavirus origins of DNA replication. Mol Cell Biol. 1992 Jun;12(6):2514–2524. doi: 10.1128/mcb.12.6.2514. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Hegde R. S., Grossman S. R., Laimins L. A., Sigler P. B. Crystal structure at 1.7 A of the bovine papillomavirus-1 E2 DNA-binding domain bound to its DNA target. Nature. 1992 Oct 8;359(6395):505–512. doi: 10.1038/359505a0. [DOI] [PubMed] [Google Scholar]
  11. Lai J. S., Herr W. Ethidium bromide provides a simple tool for identifying genuine DNA-independent protein associations. Proc Natl Acad Sci U S A. 1992 Aug 1;89(15):6958–6962. doi: 10.1073/pnas.89.15.6958. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Lambert P. F., Hubbert N. L., Howley P. M., Schiller J. T. Genetic assignment of multiple E2 gene products in bovine papillomavirus-transformed cells. J Virol. 1989 Jul;63(7):3151–3154. doi: 10.1128/jvi.63.7.3151-3154.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Lambert P. F. Papillomavirus DNA replication. J Virol. 1991 Jul;65(7):3417–3420. doi: 10.1128/jvi.65.7.3417-3420.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Li R., Knight J., Bream G., Stenlund A., Botchan M. Specific recognition nucleotides and their DNA context determine the affinity of E2 protein for 17 binding sites in the BPV-1 genome. Genes Dev. 1989 Apr;3(4):510–526. doi: 10.1101/gad.3.4.510. [DOI] [PubMed] [Google Scholar]
  15. Lu J. Z., Sun Y. N., Rose R. C., Bonnez W., McCance D. J. Two E2 binding sites (E2BS) alone or one E2BS plus an A/T-rich region are minimal requirements for the replication of the human papillomavirus type 11 origin. J Virol. 1993 Dec;67(12):7131–7139. doi: 10.1128/jvi.67.12.7131-7139.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Lusky M., Fontane E. Formation of the complex of bovine papillomavirus E1 and E2 proteins is modulated by E2 phosphorylation and depends upon sequences within the carboxyl terminus of E1. Proc Natl Acad Sci U S A. 1991 Jul 15;88(14):6363–6367. doi: 10.1073/pnas.88.14.6363. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. McKay R. D. Binding of a simian virus 40 T antigen-related protein to DNA. J Mol Biol. 1981 Jan 25;145(3):471–488. doi: 10.1016/0022-2836(81)90540-4. [DOI] [PubMed] [Google Scholar]
  18. Meyers C., Frattini M. G., Hudson J. B., Laimins L. A. Biosynthesis of human papillomavirus from a continuous cell line upon epithelial differentiation. Science. 1992 Aug 14;257(5072):971–973. doi: 10.1126/science.1323879. [DOI] [PubMed] [Google Scholar]
  19. Mohr I. J., Clark R., Sun S., Androphy E. J., MacPherson P., Botchan M. R. Targeting the E1 replication protein to the papillomavirus origin of replication by complex formation with the E2 transactivator. Science. 1990 Dec 21;250(4988):1694–1699. doi: 10.1126/science.2176744. [DOI] [PubMed] [Google Scholar]
  20. Seo Y. S., Müller F., Lusky M., Gibbs E., Kim H. Y., Phillips B., Hurwitz J. Bovine papilloma virus (BPV)-encoded E2 protein enhances binding of E1 protein to the BPV replication origin. Proc Natl Acad Sci U S A. 1993 Apr 1;90(7):2865–2869. doi: 10.1073/pnas.90.7.2865. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Seo Y. S., Müller F., Lusky M., Hurwitz J. Bovine papilloma virus (BPV)-encoded E1 protein contains multiple activities required for BPV DNA replication. Proc Natl Acad Sci U S A. 1993 Jan 15;90(2):702–706. doi: 10.1073/pnas.90.2.702. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Sun S., Thorner L., Lentz M., MacPherson P., Botchan M. Identification of a 68-kilodalton nuclear ATP-binding phosphoprotein encoded by bovine papillomavirus type 1. J Virol. 1990 Oct;64(10):5093–5105. doi: 10.1128/jvi.64.10.5093-5105.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Ustav E., Ustav M., Szymanski P., Stenlund A. The bovine papillomavirus origin of replication requires a binding site for the E2 transcriptional activator. Proc Natl Acad Sci U S A. 1993 Feb 1;90(3):898–902. doi: 10.1073/pnas.90.3.898. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Ustav M., Stenlund A. Transient replication of BPV-1 requires two viral polypeptides encoded by the E1 and E2 open reading frames. EMBO J. 1991 Feb;10(2):449–457. doi: 10.1002/j.1460-2075.1991.tb07967.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Ustav M., Ustav E., Szymanski P., Stenlund A. Identification of the origin of replication of bovine papillomavirus and characterization of the viral origin recognition factor E1. EMBO J. 1991 Dec;10(13):4321–4329. doi: 10.1002/j.1460-2075.1991.tb05010.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Wagner A. J., Small M. B., Hay N. Myc-mediated apoptosis is blocked by ectopic expression of Bcl-2. Mol Cell Biol. 1993 Apr;13(4):2432–2440. doi: 10.1128/mcb.13.4.2432. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Wilson V. G., Ludes-Meyers J. A bovine papillomavirus E1-related protein binds specifically to bovine papillomavirus DNA. J Virol. 1991 Oct;65(10):5314–5322. doi: 10.1128/jvi.65.10.5314-5322.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Wysokenski D. A., Yates J. L. Multiple EBNA1-binding sites are required to form an EBNA1-dependent enhancer and to activate a minimal replicative origin within oriP of Epstein-Barr virus. J Virol. 1989 Jun;63(6):2657–2666. doi: 10.1128/jvi.63.6.2657-2666.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Yang L., Li R., Mohr I. J., Clark R., Botchan M. R. Activation of BPV-1 replication in vitro by the transcription factor E2. Nature. 1991 Oct 17;353(6345):628–632. doi: 10.1038/353628a0. [DOI] [PubMed] [Google Scholar]

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