1887

Abstract

Our previous work demonstrated that following human cytomegalovirus (HCMV) infection of fibroblasts, there was a protein-protein interaction between the HCMV IE1-72 immediate-early (IE) protein and the cellular p107 protein which resulted in the alleviation of p107-mediated transcriptional repression of E2F-responsive promoters. In a further characterization of this interaction, we now show that IE1-72 binds to the N-terminal portion of p107, not the C-terminal ‘pocket’ region that binds E2F-4, and where a number of other viral gene products bind. Additionally, we show that exons 2 and 3 of IE1-72 are required for binding to p107. After mapping the binding domains, we next wanted to address the additional functional consequences of this interaction. It is well known that p107 can negatively regulate cell growth. To examine whether IE1-72 can also overcome this growth suppression, we transfected and infected or cotransfected various constructs into SAOS-2 cells. We showed that infection of SAOS-2 cells was capable of alleviating p107-mediated growth suppression. Additionally, we showed that IE1-72 alone is capable of overcoming p107-mediated growth arrest. Alleviation of this repression by IE1-72 is dependent on the protein-protein interaction between p107 and IE1-72 as deletion mutants of either protein which lack the identified binding domains fail to achieve this effect. These data indicate that the IE1-72 protein is capable of overcoming p107-mediated blocks in cellular proliferation, events that occur in both productive and non-productive HCMV infections.

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1999-05-01
2024-12-05
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References

  1. Bagchi S., Weinmann R., Raychaudhuri P. 1991; The retinoblastoma protein copurifies with E2F-1, an E1A-regulated inhibitor of the transcription factor E2F. Cell 65:1063–1072
    [Google Scholar]
  2. Bandara L. R., La Thangue N. B. 1991; Adenovirus E1A prevents the retinoblastoma gene product from complexing with a cellular transcription factor. Nature 351:494–497
    [Google Scholar]
  3. Beijersbergen R. L., Kerkhoven R. M., Zhu L., Carlee L., Voorhoeve P. M., Bernards R. 1994; E2F-4, a new member of the E2F gene family, has oncogenic activity and associates with p107 in vivo . Genes & Development 8:2680–2690
    [Google Scholar]
  4. Beijersbergen R. L., Carlee L., Kerkhoven R. M., Bernards R. 1995; Regulation of the retinoblastoma protein-related p107 by G1 cyclin complexes. Genes & Development 9:1340–1353
    [Google Scholar]
  5. Benson J. D., Huang E. S. 1988; Two specific topoisomerase II inhibitors prevent replication of human cytomegalovirus DNA: an implied role in replication of the viral genome. Journal of Virology 62:4797–4800
    [Google Scholar]
  6. Benson J. D., Huang E. S. 1990; Human cytomegalovirus induces expression of cellular topoisomerase II. Journal of Virology 64:9–15
    [Google Scholar]
  7. Chellappan S. P., Hiebert S., Mudryj J. M., Horowitz J. M., Nevins J. R. 1991; The E2F transcription factor is a cellular target for the RB protein. Cell 65:1053–1061
    [Google Scholar]
  8. Cherington V., Brown M., Paucha E., St Louis J., Spiegelman B. M., Roberts T. M. 1988; Separation of simian virus 40 large-T-antigen-transforming and origin-binding functions from the ability to block differentiation. Molecular and Cellular Biology 8:1380–1384
    [Google Scholar]
  9. Chittenden T., Livingston D. M., Kaelin W. F. 1991; The T/E1A-binding domain of the retinoblastoma product can interact selectively with a sequence-specific DNA binding protein. Cell 65:1073–1082
    [Google Scholar]
  10. Choi K. S., Kim S. J., Kim S. 1995; The retinoblastoma gene product negatively regulates transcriptional activation mediated by the human cytomegalovirus IE2 protein. Virology 208:450–456
    [Google Scholar]
  11. Dyson N., Buchkovich K., Whyte P., Harlow E. 1989; The cellular 107k protein that binds to adenovirus E1A also associates with the large T antigens of SV40 and JC virus. Cell 58:249–255
    [Google Scholar]
  12. Dyson N., Guida P., Munger K., Harlow E. 1992; Homologous sequences in the adenovirus E1A and human papillomavirus E7 proteins mediate interaction with the same set of cellular proteins. Journal of Virology 66:6893–6902
    [Google Scholar]
  13. Estes J., Huang E.-S. 1977; Stimulation of cellular thymidine kinase by human cytomegalovirus. Journal of Virology 24:13–21
    [Google Scholar]
  14. Ewen M. B., Xing Y., Lawrence J. B., Livingston D. M. 1991; Molecular cloning, chromosomal mapping, and expression of the cDNA for p107, a retinoblastoma gene product-related protein. Cell 66:1155–1164
    [Google Scholar]
  15. Fattaey A. R., Harlow E., Helin K. 1993; Independent regions of adenovirus E1A are required for binding to and dissociation of E2F-protein complexes. Molecular and Cellular Biology 13:7267–7277
    [Google Scholar]
  16. Ginsberg D., Vairo G., Chittenden T., Xiao Z.-X., Xu G., Wydner K., Decaprio J. A., Lawrence J. B., Livingston D. M. 1994; E2F-4, a new member of the E2F transcription factor family, interacts with p107. Genes & Development 8:2665–2679
    [Google Scholar]
  17. Greaves R. F., Mocarski E. S. 1998; Defective growth correlates with reduced accumulation of a viral DNA replication protein after low-multiplicity infection by a human cytomegalovirus ie1 mutant. Journal of Virology 72:366–379
    [Google Scholar]
  18. Hagemeier C., Caswell R., Hayhurst G., Sinclair J. H., Kouzarides T. 1994; Functional interaction between the HCMV IE2 transactivator and the retinoblastoma protein. EMBO Journal 13:2897–2903
    [Google Scholar]
  19. Hayhurst G. P., Bryant L. A., Caswell C. R., Walker S. M., Sinclair J. H. 1995; CCAAT box-dependent activation of the TATA-less human cytomegalovirus 72-kilodalton major immediate-early protein. Journal of Virology 69:182–188
    [Google Scholar]
  20. Hinds P. W., Mittnacht S., Dulic V., Arnold A., Reed S. I., Weinberg R. A. 1992; Regulat ion of retinoblastoma protein functions by ectopic expression of human cyclins. Cell 70:993–1006
    [Google Scholar]
  21. Huang E.-S., Kowalik T. F. 1993; The pathogenicity of human cytomegalovirus: an overview. In Molecular Aspects of Human Cytomegalovirus Diseases pp 1–45 Edited by Becker Y., Darai G., Huang E. S. Berlin: Springer-Verlag;
    [Google Scholar]
  22. Huang E.-S., Chen S.-T., Pagano J. S. 1973; Human cytomegalovirus. I. Purification and characterization of viral DNA. Journal of Virology 12:1473–1481
    [Google Scholar]
  23. Ikeda M. A., Nevins J. R. 1993; Identification of distinct roles for separate E1A domains in disruption of E2F complexes. Molecular and Cellular Biology 13:7029–7035
    [Google Scholar]
  24. Jault M. F., Jault J.-M., Ruchti F., Fortunato E. A., Clark C., Corbeil J., Richman D. D., Spector D. H. 1995; Cytomegalovirus infection induces high levels of cyclins, phosphorylated Rb, and p53, leading to cell cycle arrest. Journal of Virology 69:6697–6704
    [Google Scholar]
  25. Kaelin W. G., Ewen M. E., Livingston D. M. 1990; Definition of the minimal simian virus 40 large T antigen- and adenovirus ElA-binding domain in the retinoblastoma gene product. Molecular and Cellular Biology 10:3761–3769
    [Google Scholar]
  26. Kowalik T. F., Yurochko A. D., Rinehart C. A., Lee C. Y., Huang E. S. 1994; Productive infection of human endometrial stromal cells by human cytomegalovirus. Virology 202:247–257
    [Google Scholar]
  27. Lukac D. M., Harel N. Y., Tanese N., Alwine J. C. 1997; TAF-like functions of human cytomegalovirus immediate-early proteins. Journal of Virology 71:7227–7239
    [Google Scholar]
  28. Lukas J., Petersen B. O., Holm K., Bartek J., Helin K. 1996; Deregulated expression of E2F family members induces S-phase entry and overcomes p16lNK4A-mediated growth suppression. Molecular and Cellular Biology 16:1047–057
    [Google Scholar]
  29. Margolis M. J., Pajovic S., Wong E. L., Wade M., Jupp R., Nelson J. A., Azizkhan J. C. 1995; Interaction of the 72-kilodalton human cytomegalovirus IE1 gene product with E2F1 coincides with E2F-dependent activation of dihydrofolate reductase transcription. Journal of Virology 69:7759–7767
    [Google Scholar]
  30. Mocarski E. S., Kemble G. W., Lyle J. M., Greaves R. F. 1996; A deletion mutant in the human cytomegalovirus gene encoding IE1491aa is replication defective due to failure in autoregulation. Proceedings of the National Academy of Sciences, USA 93:11321–11326
    [Google Scholar]
  31. Pajovic S., Wong E. L., Black A. R., Azizkhan J. C. 1997; Identification of a viral kinase that phosphorylates specific E2Fs and pocket proteins. Molecular and Cellular Biology 17:6459–6464
    [Google Scholar]
  32. Poma E. E., Kowalik T. F., Zhu L., Sinclair J. H., Huang E.-S. 1996; The human cytomegalovirus IE1-72 protein interacts with the cellular p107 protein and relieves p107-mediated transcriptional repression of an E2F-responsive promoter. Journal of Virology 70:7867–7877
    [Google Scholar]
  33. Sambucetti L. C., Cherrington J. M., Wilkinson G. W., Mocarski E. S. 1989; NF-k B activation of the cytomegalovirus enhancer is mediated by a viral transactivator and by T cell stimulation. EMBO Journal 8:4251–4258
    [Google Scholar]
  34. Schwartz J. K., Devoto S. H., Smith E. J., Chellappan S. P., Jakoi L., Nevins J. R. 1993; Interactions of the p107 and pRb proteins with E2F during the cell proliferation response. EMBO Journal 12:1013–1020
    [Google Scholar]
  35. Shen C. Y., Ho M. S., Chang S. F., Yen M. S., Ng H. T., Huang E.-S., Wu C. W. 1993; High rate of concurrent genital infections with human cytomegalovirus and human papillomaviruses in cervical cancer patients. Journal of Infectious Diseases 168:449–452
    [Google Scholar]
  36. Speir E., Modali R., Huang E. S., Leon M. B., Shawl F., Finkel T., Epstein S. E. 1994; Potential role of human cytomegalovirus and p53 interaction in coronary restenosis. Science 265:391–394
    [Google Scholar]
  37. Stenberg R. M. 1993; Immediate-early genes of human cytomegalovirus: organization and function. In Molecular Aspects of Human Cytomegalovirus Diseases pp 330–359 Edited by Becker Y., Darai G., Huang E. S. Berlin: Springer-Verlag;
    [Google Scholar]
  38. Wade M., Kowalik T. F., Mudryj M., Huang E.-S., Azizkhan J. C. 1992; E2F mediates dihydrofolate reductase promoter activation and multiprotein complex formation in human cytomegalovirus infection. Molecular and Cellular Biology 12:4364–4374
    [Google Scholar]
  39. Weinberg R. A. 1991; Tumor suppressor genes. Science 254:1138–1146
    [Google Scholar]
  40. Weinberg R. A. 1995; The retinoblastoma protein and cell cycle control. Cell 81:323–330
    [Google Scholar]
  41. Yurochko A. D., Kowalik T. F., Huong S.-M., Huang E.-S. 1995; HCMV upregulates NF-k B activity by transactivating the NF-k B p105/p50- and p65-promoters. Journal of Virology 69:5391–5400
    [Google Scholar]
  42. Zamanian M., La Thangue N. B. 1993; Transcriptional repression by the Rb-related protein p107. Molecular and Cellular Biology 4:389–396
    [Google Scholar]
  43. Zhu L., van den Heuvel S., Helin K., Fattaey A., Ewen M., Livingston D. M., Dyson N., Harlow E. 1993; Inhibition of cell proliferation by p107, a relative of the retinoblastoma protein. Genes & Development 7:1111–1125
    [Google Scholar]
  44. Zhu H., Shen Y., Shenk T. 1995a; Human cytomegalovirus IE1 and IE2 proteins block apoptosis. Journal of Virology 69:7960–7970
    [Google Scholar]
  45. Zhu L., Enders G., Lees J. A., Beijersbergen R. L., Bernards R., Harlow E. 1995b; The pRb-related protein p107 contains two growth suppression domains : independent interactions with E2F and cyclin/cdk complexes. EMBO Journal 14:1904–1913
    [Google Scholar]
  46. Zhu L., Harlow E., Dynlacht B. D. 1995c; p107 uses a p21-related domain to bind cyclin/cdk2 and regulate interactions with E2F. Genes & Development 9:1740–1752
    [Google Scholar]
  47. Zhu L., Xie E., Chang L. S. 1995d; Differential roles oftwo tandem E2F sites in repression of the human p107 promoter by retinoblastoma and p107 proteins. Molecular and Cellular Biology 15:3552–3562
    [Google Scholar]
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