Skip to main content
Nucleic Acids Research logoLink to Nucleic Acids Research
. 1991 May 11;19(9):2363–2371. doi: 10.1093/nar/19.9.2363

Delineation of human papillomavirus type 18 enhancer binding proteins: the intracellular distribution of a novel octamer binding protein p92 is cell cycle regulated.

H D Royer 1, M P Freyaldenhoven 1, I Napierski 1, D D Spitkovsky 1, T Bauknecht 1, N Dathan 1
PMCID: PMC329444  PMID: 1645869

Abstract

The enhancer of human papillomavirus type 18 consists of two functionally redundant domains, one is partially conserved between HPV18 and HPV16, both mediate strong transcriptional enhancement. In contrast, short fragments of the enhancer mediate low transcriptional enhancement, suggesting that there is functional cooperation between HPV enhancer binding factors. Previously interactions of the enhancer with NF-1, AP1 and steroid receptors were shown by EMSA. Here we show by binding site blotting, that four novel sequence specific proteins p110, p92, p42 and p40 bind to the enhancer. Nuclear proteins p110 and p92 bind at repeated sites in the enhancer, proteins p42 and p40 only at one site. Recognition sequences for p110 and p92 were identified in a TTGCTTGCATAA sequence motif and consist of an overlapping p110 and p92 recognition site. The specific interaction of p110 with G residues of this 12 nucleotide long sequence was demonstrated by a mutant recognition site. Single recognition sites for p42 and p40 were localized in the enhancer by the use of overlapping oligonucleotides. In addition, electrophoretic mobility shift analysis identified Oct-1 and AP2 interactions with the enhancer. The AP2 binding site was mapped to a AGGCACATATT motif. The p92 protein binds to enhancer oligonucleotides, containing at least one copy of Oct-1 like recognition sequences, these oligonucleotides also bind synthetic Oct-1 protein. During serum starvation or at high saturation density, p92 moves from the nucleus into the cytoplasm. Immunoblots of cytoplasmic extracts with anti-Oct-1 antisera showed, that p92 is a novel octamer binding factor, which is not immunologically related to the Oct-1 protein. The intracellular p92 distribution is regulated at the G0/G1 boundary of the cell cycle, by nucleo-cytoplasmic translocation.

Full text

PDF
2363

Images in this article

Selected References

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

  1. Baeuerle P. A., Baltimore D. Activation of DNA-binding activity in an apparently cytoplasmic precursor of the NF-kappa B transcription factor. Cell. 1988 Apr 22;53(2):211–217. doi: 10.1016/0092-8674(88)90382-0. [DOI] [PubMed] [Google Scholar]
  2. Baeuerle P. A., Baltimore D. I kappa B: a specific inhibitor of the NF-kappa B transcription factor. Science. 1988 Oct 28;242(4878):540–546. doi: 10.1126/science.3140380. [DOI] [PubMed] [Google Scholar]
  3. Baker C. C., Phelps W. C., Lindgren V., Braun M. J., Gonda M. A., Howley P. M. Structural and transcriptional analysis of human papillomavirus type 16 sequences in cervical carcinoma cell lines. J Virol. 1987 Apr;61(4):962–971. doi: 10.1128/jvi.61.4.962-971.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Baumruker T., Sturm R., Herr W. OBP100 binds remarkably degenerate octamer motifs through specific interactions with flanking sequences. Genes Dev. 1988 Nov;2(11):1400–1413. doi: 10.1101/gad.2.11.1400. [DOI] [PubMed] [Google Scholar]
  5. Boshart M., Gissmann L., Ikenberg H., Kleinheinz A., Scheurlen W., zur Hausen H. A new type of papillomavirus DNA, its presence in genital cancer biopsies and in cell lines derived from cervical cancer. EMBO J. 1984 May;3(5):1151–1157. doi: 10.1002/j.1460-2075.1984.tb01944.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Broach J. R., Li Y. Y., Feldman J., Jayaram M., Abraham J., Nasmyth K. A., Hicks J. B. Localization and sequence analysis of yeast origins of DNA replication. Cold Spring Harb Symp Quant Biol. 1983;47(Pt 2):1165–1173. doi: 10.1101/sqb.1983.047.01.132. [DOI] [PubMed] [Google Scholar]
  7. Chong T., Chan W. K., Bernard H. U. Transcriptional activation of human papillomavirus 16 by nuclear factor I, AP1, steroid receptors and a possibly novel transcription factor, PVF: a model for the composition of genital papillomavirus enhancers. Nucleic Acids Res. 1990 Feb 11;18(3):465–470. doi: 10.1093/nar/18.3.465. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Cripe T. P., Alderborn A., Anderson R. D., Parkkinen S., Bergman P., Haugen T. H., Pettersson U., Turek L. P. Transcriptional activation of the human papillomavirus-16 P97 promoter by an 88-nucleotide enhancer containing distinct cell-dependent and AP-1-responsive modules. New Biol. 1990 May;2(5):450–463. [PubMed] [Google Scholar]
  9. Cripe T. P., Haugen T. H., Turk J. P., Tabatabai F., Schmid P. G., 3rd, Dürst M., Gissmann L., Roman A., Turek L. P. Transcriptional regulation of the human papillomavirus-16 E6-E7 promoter by a keratinocyte-dependent enhancer, and by viral E2 trans-activator and repressor gene products: implications for cervical carcinogenesis. EMBO J. 1987 Dec 1;6(12):3745–3753. doi: 10.1002/j.1460-2075.1987.tb02709.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Crook T., Morgenstern J. P., Crawford L., Banks L. Continued expression of HPV-16 E7 protein is required for maintenance of the transformed phenotype of cells co-transformed by HPV-16 plus EJ-ras. EMBO J. 1989 Feb;8(2):513–519. doi: 10.1002/j.1460-2075.1989.tb03405.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Davidson I., Fromental C., Augereau P., Wildeman A., Zenke M., Chambon P. Cell-type specific protein binding to the enhancer of simian virus 40 in nuclear extracts. Nature. 1986 Oct 9;323(6088):544–548. doi: 10.1038/323544a0. [DOI] [PubMed] [Google Scholar]
  12. DeCaprio J. A., Ludlow J. W., Lynch D., Furukawa Y., Griffin J., Piwnica-Worms H., Huang C. M., Livingston D. M. The product of the retinoblastoma susceptibility gene has properties of a cell cycle regulatory element. Cell. 1989 Sep 22;58(6):1085–1095. doi: 10.1016/0092-8674(89)90507-2. [DOI] [PubMed] [Google Scholar]
  13. Dyson N., Howley P. M., Münger K., Harlow E. The human papilloma virus-16 E7 oncoprotein is able to bind to the retinoblastoma gene product. Science. 1989 Feb 17;243(4893):934–937. doi: 10.1126/science.2537532. [DOI] [PubMed] [Google Scholar]
  14. Dürst M., Kleinheinz A., Hotz M., Gissmann L. The physical state of human papillomavirus type 16 DNA in benign and malignant genital tumours. J Gen Virol. 1985 Jul;66(Pt 7):1515–1522. doi: 10.1099/0022-1317-66-7-1515. [DOI] [PubMed] [Google Scholar]
  15. Elsholtz H. P., Albert V. R., Treacy M. N., Rosenfeld M. G. A two-base change in a POU factor-binding site switches pituitary-specific to lymphoid-specific gene expression. Genes Dev. 1990 Jan;4(1):43–51. doi: 10.1101/gad.4.1.43. [DOI] [PubMed] [Google Scholar]
  16. Falkner F. G., Zachau H. G. Correct transcription of an immunoglobulin kappa gene requires an upstream fragment containing conserved sequence elements. Nature. 1984 Jul 5;310(5972):71–74. doi: 10.1038/310071a0. [DOI] [PubMed] [Google Scholar]
  17. Finlay C. A., Hinds P. W., Levine A. J. The p53 proto-oncogene can act as a suppressor of transformation. Cell. 1989 Jun 30;57(7):1083–1093. doi: 10.1016/0092-8674(89)90045-7. [DOI] [PubMed] [Google Scholar]
  18. Fletcher C., Heintz N., Roeder R. G. Purification and characterization of OTF-1, a transcription factor regulating cell cycle expression of a human histone H2b gene. Cell. 1987 Dec 4;51(5):773–781. doi: 10.1016/0092-8674(87)90100-0. [DOI] [PubMed] [Google Scholar]
  19. Freyaldenhoven M. P., Royer-Pokora B., Napierski I., Royer H. D. DNA binding proteins present in guanidinium isothiocyanate lysates of cells are suitable for specific binding site blotting. Nucleic Acids Res. 1989 Nov 11;17(21):8891–8891. doi: 10.1093/nar/17.21.8891. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Friend S. H., Bernards R., Rogelj S., Weinberg R. A., Rapaport J. M., Albert D. M., Dryja T. P. A human DNA segment with properties of the gene that predisposes to retinoblastoma and osteosarcoma. Nature. 1986 Oct 16;323(6089):643–646. doi: 10.1038/323643a0. [DOI] [PubMed] [Google Scholar]
  21. Garcia-Carranca A., Thierry F., Yaniv M. Interplay of viral and cellular proteins along the long control region of human papillomavirus type 18. J Virol. 1988 Nov;62(11):4321–4330. doi: 10.1128/jvi.62.11.4321-4330.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Gius D., Grossman S., Bedell M. A., Laimins L. A. Inducible and constitutive enhancer domains in the noncoding region of human papillomavirus type 18. J Virol. 1988 Mar;62(3):665–672. doi: 10.1128/jvi.62.3.665-672.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. Gloss B., Bernard H. U. The E6/E7 promoter of human papillomavirus type 16 is activated in the absence of E2 proteins by a sequence-aberrant Sp1 distal element. J Virol. 1990 Nov;64(11):5577–5584. doi: 10.1128/jvi.64.11.5577-5584.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Gloss B., Chong T., Bernard H. U. Numerous nuclear proteins bind the long control region of human papillomavirus type 16: a subset of 6 of 23 DNase I-protected segments coincides with the location of the cell-type-specific enhancer. J Virol. 1989 Mar;63(3):1142–1152. doi: 10.1128/jvi.63.3.1142-1152.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Gloss B., Yeo-Gloss M., Meisterenst M., Rogge L., Winnacker E. L., Bernard H. U. Clusters of nuclear factor I binding sites identify enhancers of several papillomaviruses but alone are not sufficient for enhancer function. Nucleic Acids Res. 1989 May 11;17(9):3519–3533. doi: 10.1093/nar/17.9.3519. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Goldfarb D. S., Gariépy J., Schoolnik G., Kornberg R. D. Synthetic peptides as nuclear localization signals. Nature. 1986 Aug 14;322(6080):641–644. doi: 10.1038/322641a0. [DOI] [PubMed] [Google Scholar]
  27. Hawley-Nelson P., Vousden K. H., Hubbert N. L., Lowy D. R., Schiller J. T. HPV16 E6 and E7 proteins cooperate to immortalize human foreskin keratinocytes. EMBO J. 1989 Dec 1;8(12):3905–3910. doi: 10.1002/j.1460-2075.1989.tb08570.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Herr W., Clarke J. The SV40 enhancer is composed of multiple functional elements that can compensate for one another. Cell. 1986 May 9;45(3):461–470. doi: 10.1016/0092-8674(86)90332-6. [DOI] [PubMed] [Google Scholar]
  29. Herr W., Sturm R. A., Clerc R. G., Corcoran L. M., Baltimore D., Sharp P. A., Ingraham H. A., Rosenfeld M. G., Finney M., Ruvkun G. The POU domain: a large conserved region in the mammalian pit-1, oct-1, oct-2, and Caenorhabditis elegans unc-86 gene products. Genes Dev. 1988 Dec;2(12A):1513–1516. doi: 10.1101/gad.2.12a.1513. [DOI] [PubMed] [Google Scholar]
  30. Imagawa M., Chiu R., Karin M. Transcription factor AP-2 mediates induction by two different signal-transduction pathways: protein kinase C and cAMP. Cell. 1987 Oct 23;51(2):251–260. doi: 10.1016/0092-8674(87)90152-8. [DOI] [PubMed] [Google Scholar]
  31. Johnson P. F., McKnight S. L. Eukaryotic transcriptional regulatory proteins. Annu Rev Biochem. 1989;58:799–839. doi: 10.1146/annurev.bi.58.070189.004055. [DOI] [PubMed] [Google Scholar]
  32. Kemler I., Schreiber E., Müller M. M., Matthias P., Schaffner W. Octamer transcription factors bind to two different sequence motifs of the immunoglobulin heavy chain promoter. EMBO J. 1989 Jul;8(7):2001–2008. doi: 10.1002/j.1460-2075.1989.tb03607.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Kissinger C. R., Liu B. S., Martin-Blanco E., Kornberg T. B., Pabo C. O. Crystal structure of an engrailed homeodomain-DNA complex at 2.8 A resolution: a framework for understanding homeodomain-DNA interactions. Cell. 1990 Nov 2;63(3):579–590. doi: 10.1016/0092-8674(90)90453-l. [DOI] [PubMed] [Google Scholar]
  34. LaBella F., Sive H. L., Roeder R. G., Heintz N. Cell-cycle regulation of a human histone H2b gene is mediated by the H2b subtype-specific consensus element. Genes Dev. 1988 Jan;2(1):32–39. doi: 10.1101/gad.2.1.32. [DOI] [PubMed] [Google Scholar]
  35. Laemmli U. K. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature. 1970 Aug 15;227(5259):680–685. doi: 10.1038/227680a0. [DOI] [PubMed] [Google Scholar]
  36. Lanford R. E., Kanda P., Kennedy R. C. Induction of nuclear transport with a synthetic peptide homologous to the SV40 T antigen transport signal. Cell. 1986 Aug 15;46(4):575–582. doi: 10.1016/0092-8674(86)90883-4. [DOI] [PubMed] [Google Scholar]
  37. Lehn H., Villa L. L., Marziona F., Hilgarth M., Hillemans H. G., Sauer G. Physical state and biological activity of human papillomavirus genomes in precancerous lesions of the female genital tract. J Gen Virol. 1988 Jan;69(Pt 1):187–196. doi: 10.1099/0022-1317-69-1-187. [DOI] [PubMed] [Google Scholar]
  38. Ludlow J. W., Shon J., Pipas J. M., Livingston D. M., DeCaprio J. A. The retinoblastoma susceptibility gene product undergoes cell cycle-dependent dephosphorylation and binding to and release from SV40 large T. Cell. 1990 Feb 9;60(3):387–396. doi: 10.1016/0092-8674(90)90590-b. [DOI] [PubMed] [Google Scholar]
  39. Markland W., Smith A. E., Roberts B. L. Signal-dependent translocation of simian virus 40 large-T antigen into rat liver nuclei in a cell-free system. Mol Cell Biol. 1987 Dec;7(12):4255–4265. doi: 10.1128/mcb.7.12.4255. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Miskimins W. K., Roberts M. P., McClelland A., Ruddle F. H. Use of a protein-blotting procedure and a specific DNA probe to identify nuclear proteins that recognize the promoter region of the transferrin receptor gene. Proc Natl Acad Sci U S A. 1985 Oct;82(20):6741–6744. doi: 10.1073/pnas.82.20.6741. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Mitchell P. J., Wang C., Tjian R. Positive and negative regulation of transcription in vitro: enhancer-binding protein AP-2 is inhibited by SV40 T antigen. Cell. 1987 Sep 11;50(6):847–861. doi: 10.1016/0092-8674(87)90512-5. [DOI] [PubMed] [Google Scholar]
  42. Müller M. M., Ruppert S., Schaffner W., Matthias P. A cloned octamer transcription factor stimulates transcription from lymphoid-specific promoters in non-B cells. Nature. 1988 Dec 8;336(6199):544–551. doi: 10.1038/336544a0. [DOI] [PubMed] [Google Scholar]
  43. Münger K., Phelps W. C., Bubb V., Howley P. M., Schlegel R. The E6 and E7 genes of the human papillomavirus type 16 together are necessary and sufficient for transformation of primary human keratinocytes. J Virol. 1989 Oct;63(10):4417–4421. doi: 10.1128/jvi.63.10.4417-4421.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Pardee A. B. G1 events and regulation of cell proliferation. Science. 1989 Nov 3;246(4930):603–608. doi: 10.1126/science.2683075. [DOI] [PubMed] [Google Scholar]
  45. Parslow T. G., Blair D. L., Murphy W. J., Granner D. K. Structure of the 5' ends of immunoglobulin genes: a novel conserved sequence. Proc Natl Acad Sci U S A. 1984 May;81(9):2650–2654. doi: 10.1073/pnas.81.9.2650. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Pruijn J. M., van der Vliet P. C., Dathan N. A., Mattaj I. W. Anti-OTF-1 antibodies inhibit NFIII stimulation of in vitro adenovirus DNA replication. Nucleic Acids Res. 1989 Mar 11;17(5):1845–1863. doi: 10.1093/nar/17.5.1845. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Rabson M. S., Yee C., Yang Y. C., Howley P. M. Bovine papillomavirus type 1 3' early region transformation and plasmid maintenance functions. J Virol. 1986 Nov;60(2):626–634. doi: 10.1128/jvi.60.2.626-634.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Rauscher F. J., 3rd, Voulalas P. J., Franza B. R., Jr, Curran T. Fos and Jun bind cooperatively to the AP-1 site: reconstitution in vitro. Genes Dev. 1988 Dec;2(12B):1687–1699. doi: 10.1101/gad.2.12b.1687. [DOI] [PubMed] [Google Scholar]
  49. Roth S., Stein D., Nüsslein-Volhard C. A gradient of nuclear localization of the dorsal protein determines dorsoventral pattern in the Drosophila embryo. Cell. 1989 Dec 22;59(6):1189–1202. doi: 10.1016/0092-8674(89)90774-5. [DOI] [PubMed] [Google Scholar]
  50. Rushlow C. A., Han K., Manley J. L., Levine M. The graded distribution of the dorsal morphogen is initiated by selective nuclear transport in Drosophila. Cell. 1989 Dec 22;59(6):1165–1177. doi: 10.1016/0092-8674(89)90772-1. [DOI] [PubMed] [Google Scholar]
  51. Santoro C., Mermod N., Andrews P. C., Tjian R. A family of human CCAAT-box-binding proteins active in transcription and DNA replication: cloning and expression of multiple cDNAs. Nature. 1988 Jul 21;334(6179):218–224. doi: 10.1038/334218a0. [DOI] [PubMed] [Google Scholar]
  52. Schneider-Maunoury S., Croissant O., Orth G. Integration of human papillomavirus type 16 DNA sequences: a possible early event in the progression of genital tumors. J Virol. 1987 Oct;61(10):3295–3298. doi: 10.1128/jvi.61.10.3295-3298.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Schwarz E., Freese U. K., Gissmann L., Mayer W., Roggenbuck B., Stremlau A., zur Hausen H. Structure and transcription of human papillomavirus sequences in cervical carcinoma cells. Nature. 1985 Mar 7;314(6006):111–114. doi: 10.1038/314111a0. [DOI] [PubMed] [Google Scholar]
  54. Scott M. P., Tamkun J. W., Hartzell G. W., 3rd The structure and function of the homeodomain. Biochim Biophys Acta. 1989 Jul 28;989(1):25–48. doi: 10.1016/0304-419x(89)90033-4. [DOI] [PubMed] [Google Scholar]
  55. Sealey L., Chalkley R. At least two nuclear proteins bind specifically to the Rous sarcoma virus long terminal repeat enhancer. Mol Cell Biol. 1987 Feb;7(2):787–798. doi: 10.1128/mcb.7.2.787. [DOI] [PMC free article] [PubMed] [Google Scholar]
  56. Sibbet G. J., Campo M. S. Multiple interactions between cellular factors and the non-coding region of human papillomavirus type 16. J Gen Virol. 1990 Nov;71(Pt 11):2699–2707. doi: 10.1099/0022-1317-71-11-2699. [DOI] [PubMed] [Google Scholar]
  57. Singh H., Sen R., Baltimore D., Sharp P. A. A nuclear factor that binds to a conserved sequence motif in transcriptional control elements of immunoglobulin genes. Nature. 1986 Jan 9;319(6049):154–158. doi: 10.1038/319154a0. [DOI] [PubMed] [Google Scholar]
  58. Stanbridge E. J., Der C. J., Doersen C. J., Nishimi R. Y., Peehl D. M., Weissman B. E., Wilkinson J. E. Human cell hybrids: analysis of transformation and tumorigenicity. Science. 1982 Jan 15;215(4530):252–259. doi: 10.1126/science.7053574. [DOI] [PubMed] [Google Scholar]
  59. Steward R. Relocalization of the dorsal protein from the cytoplasm to the nucleus correlates with its function. Cell. 1989 Dec 22;59(6):1179–1188. doi: 10.1016/0092-8674(89)90773-3. [DOI] [PubMed] [Google Scholar]
  60. Sturm R. A., Das G., Herr W. The ubiquitous octamer-binding protein Oct-1 contains a POU domain with a homeo box subdomain. Genes Dev. 1988 Dec;2(12A):1582–1599. doi: 10.1101/gad.2.12a.1582. [DOI] [PubMed] [Google Scholar]
  61. Sturm R., Baumruker T., Franza B. R., Jr, Herr W. A 100-kD HeLa cell octamer binding protein (OBP100) interacts differently with two separate octamer-related sequences within the SV40 enhancer. Genes Dev. 1987 Dec;1(10):1147–1160. doi: 10.1101/gad.1.10.1147. [DOI] [PubMed] [Google Scholar]
  62. Swift F. V., Bhat K., Younghusband H. B., Hamada H. Characterization of a cell type-specific enhancer found in the human papilloma virus type 18 genome. EMBO J. 1987 May;6(5):1339–1344. doi: 10.1002/j.1460-2075.1987.tb02373.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  63. Thierry F., Heard J. M., Dartmann K., Yaniv M. Characterization of a transcriptional promoter of human papillomavirus 18 and modulation of its expression by simian virus 40 and adenovirus early antigens. J Virol. 1987 Jan;61(1):134–142. doi: 10.1128/jvi.61.1.134-142.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  64. Tidy J., Vousden K. H., Mason P., Farrell P. J. A novel deletion within the upstream regulatory region of episomal human papillomavirus type 16. J Gen Virol. 1989 Apr;70(Pt 4):999–1004. doi: 10.1099/0022-1317-70-4-999. [DOI] [PubMed] [Google Scholar]
  65. Vinson C. R., LaMarco K. L., Johnson P. F., Landschulz W. H., McKnight S. L. In situ detection of sequence-specific DNA binding activity specified by a recombinant bacteriophage. Genes Dev. 1988 Jul;2(7):801–806. doi: 10.1101/gad.2.7.801. [DOI] [PubMed] [Google Scholar]
  66. Vousden K. H., Doniger J., DiPaolo J. A., Lowy D. R. The E7 open reading frame of human papillomavirus type 16 encodes a transforming gene. Oncogene Res. 1988 Sep;3(2):167–175. [PubMed] [Google Scholar]
  67. Vousden K. H. Human papillomaviruses and cervical carcinoma. Cancer Cells. 1989 Oct;1(2):43–50. [PubMed] [Google Scholar]
  68. Watanabe S., Kanda T., Yoshiike K. Human papillomavirus type 16 transformation of primary human embryonic fibroblasts requires expression of open reading frames E6 and E7. J Virol. 1989 Feb;63(2):965–969. doi: 10.1128/jvi.63.2.965-969.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  69. Werness B. A., Levine A. J., Howley P. M. Association of human papillomavirus types 16 and 18 E6 proteins with p53. Science. 1990 Apr 6;248(4951):76–79. doi: 10.1126/science.2157286. [DOI] [PubMed] [Google Scholar]
  70. Williams T., Admon A., Lüscher B., Tjian R. Cloning and expression of AP-2, a cell-type-specific transcription factor that activates inducible enhancer elements. Genes Dev. 1988 Dec;2(12A):1557–1569. doi: 10.1101/gad.2.12a.1557. [DOI] [PubMed] [Google Scholar]
  71. Wingender E. Compilation of transcription regulating proteins. Nucleic Acids Res. 1988 Mar 25;16(5):1879–1902. doi: 10.1093/nar/16.5.1879. [DOI] [PMC free article] [PubMed] [Google Scholar]
  72. Wu C. An exonuclease protection assay reveals heat-shock element and TATA box DNA-binding proteins in crude nuclear extracts. Nature. 1985 Sep 5;317(6032):84–87. doi: 10.1038/317084a0. [DOI] [PubMed] [Google Scholar]
  73. von Knebel Doeberitz M., Oltersdorf T., Schwarz E., Gissmann L. Correlation of modified human papilloma virus early gene expression with altered growth properties in C4-1 cervical carcinoma cells. Cancer Res. 1988 Jul 1;48(13):3780–3786. [PubMed] [Google Scholar]

Articles from Nucleic Acids Research are provided here courtesy of Oxford University Press

RESOURCES