Advertisement

Foamy Virus Transactivation and Gene Expression

Chapter
Part of the Current Topics in Microbiology and Immunology book series (CT MICROBIOLOGY, volume 277)

Abstract

An overview of the pattern and mechanisms of spuma or foamy virus (FV) gene expression is presented. FVs are complex retroviruses with respect to their genetic outfit and the elements used to control and regulate expression of the viral genome. The increased insight into transcriptional and posttranscriptional mechanisms has revealed that the FVs are distinct, unconventional retroviruses clearly apart from the orthoretroviruses. Although less characterized than the orthoretroviruses, FVs have several unique features that are important for construction and assembly of FV-based vectors for targeted gene delivery and vaccination purposes. Some of these distinguishing features are directly related to the FV-specific mechanisms of gene expression and include (1) the presence of an internal, functional active second transcription unit for expression of the nonstructural genes, (2) the utilization of a subgenomic, spliced transcript for Pol protein expression, and (3) distinct but not yet understood mechanisms for the nuclear exit of defined transcripts and thus an additional level of posttranscriptional control of gene expression. Finally, the interactions of the viral transactivator not only with both viral promoters but also with regulatory elements controlling the expression of defined cellular genes are an important issue with respect to vector development and the apparent apathogenicity of FVs in their natural hosts.

Keywords

Human Immunodeficiency Virus Type Long Terminal Repeat Foamy Virus Cellular Gene Expression Simian Foamy Virus 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Adachi A, Sakai H, Tokunaga K, Kawamura M (1995) Functional analysis of human spuma retrovirus genome. Virus Genes 11:15–20PubMedCrossRefGoogle Scholar
  2. Alke A, Schwantes A, Kido K, Flötenmeyer M, Flügel RM, Löchelt M (2001) The bet gene of feline foamy virus is required for virus replication. Virology 287:310–320PubMedCrossRefGoogle Scholar
  3. Alke A, Schwantes A, Zemba M, Flügel RM, Löchelt M (2000) Characterization of the humoral immune response and virus replication in cats experimentally infected with feline foamy virus. Virology 275:170–176PubMedCrossRefGoogle Scholar
  4. Baldwin DN, Linial ML (1998) The roles of pol and env in the assembly pathway of human foamy virus. J Virol 72:3658–3665PubMedGoogle Scholar
  5. Baunach G, Maurer B, Hahn H, Kranz M, Rethwilm A (1993) Functional analysis of human foamy virus accessory reading frames. J Virol 67:5411–5418PubMedGoogle Scholar
  6. Blair WS, Bogerd H, Cullen BR (1994) Genetic analysis indicates that the human foamy virus Bel-1 protein contains a transcription activation domain of the acidic class. J Virol 68:3803–3808PubMedGoogle Scholar
  7. Bock M, Heinkelein M, Lindemann D, Rethwilm A (1998) Cells expressing the human foamy virus (HFV) accessory Bet protein are resistant to productive HFV superinfection. Virology 250:194–204PubMedCrossRefGoogle Scholar
  8. Bodem J, Löchelt M, Delius H, Flügel RM (1998a) Detection of subgenomic cDNAs and mapping of feline foamy virus mRNAs reveals complex patterns of transcription. Virology 244:417–426CrossRefGoogle Scholar
  9. Bodem J, Löchelt M, Winkler I, Flower RP, Delius H, Flügel RM (1996) Characterization of the spliced pol transcript of feline foamy virus: the splice acceptor site of the pol transcript is located in gag of foamy viruses. J Virol 70:9024–9027PubMedGoogle Scholar
  10. Bodem J, Löchelt M, Yang P, Flügel RM (1997) Regulation of gene expression by human foamy virus and potentials of foamy viral vectors. Stem Cells 15:141–147PubMedCrossRefGoogle Scholar
  11. Bodem J, Zemba M, Flügel RM (1998b) Nuclear localization of the functional Bel 1 transactivator but not of the gag proteins of the feline foamy virus. Virology 251:22–27CrossRefGoogle Scholar
  12. Bray M, Prasad S, Dubay JW, Hunter E, Jeang KT, Rekosh D, Hammarskjold ML (1994) A small element from the Mason-Pfizer monkey virus genome makes human immunodeficiency virus type 1 expression and replication Rev-independent. Proc Natl Acad Sci U S A 91:1256–1260PubMedCrossRefGoogle Scholar
  13. Butsch M, Boris-Lawrie K (2002) Destiny of unspliced retroviral RNA: ribosome and/or virion? J Virol 76:3089–3094PubMedCrossRefGoogle Scholar
  14. Campbell M, Eng C, Luciw PA (1996) The simian foamy virus type 1 transcriptional transactivator (Tas) binds and activates an enhancer element in the gag gene. J Virol 70:6847–6855PubMedGoogle Scholar
  15. Campbell M, Renshaw-Gegg L, Renne R, Luciw PA (1994) Characterization of the internal promoter of simian foamy viruses. J Virol 68:4811–4820PubMedGoogle Scholar
  16. Carter, KC Wang, L Shell, LK Zamir, I Berger, SL Moore PA (1997) The human transcriptional adaptor genes TADA2L and GCN5L2 colocalize to chromosome 17q12-q21 and display a similar tissue expression pattern. Genomics 40:497–500PubMedCrossRefGoogle Scholar
  17. Chang J, Lee KJ, Jong KL, Lee EK, Baek GH, Sung YC (1995) Human foamy virus Bell transactivator contains a bipartite nuclear localization determinant which is sensitive to protein context and triple multimerization domains. J Virol 69:801–808PubMedGoogle Scholar
  18. Coffin, J. M. 1996. Retroviridae and their replication. In Fields, BN Knipe, DM Howley PM (eds) Virology. Raven Press, New YorkGoogle Scholar
  19. Colas S, Bourge JF, Wybier J, Chelbi-Alix MK, Paul P, Emanoil-Ravier R (1995) Human foamy virus infection activates class I major histocompatibility complex antigen expression. J Gen Virol 76:661–667PubMedCrossRefGoogle Scholar
  20. Cullen BR (1991) Human immunodeficiency virus as a prototypic complex retrovirus. J Virol 65:1053–1056PubMedGoogle Scholar
  21. Cullen BR (1992) Mechanism of action of regulatory proteins encoded by complex retroviruses. Microbiol Rev 56:375–394PubMedGoogle Scholar
  22. Cullen BR (2000a) Connections between the processing and nuclear export of mRNA: evidence for an export license? Proc Natl Acad Sci U S A 97:4–6CrossRefGoogle Scholar
  23. Cullen BR (2000b) Nuclear RNA export pathways. Mol Cell Biol 20:4181–4187CrossRefGoogle Scholar
  24. Enssle J, Jordan I, Mauer B, Rethwilm A (1996) Foamy virus reverse transcriptase is expressed independently from the Gag protein. Proc Natl Acad Sci U S A 93:4137–4141PubMedCrossRefGoogle Scholar
  25. Erlwein O, Rethwilm A (1993) BEL-1 transactivator responsive sequences in the long terminal repeat of human foamy virus. Virology 196:256–268PubMedCrossRefGoogle Scholar
  26. Falcone V, Leupold J, Clotten J, Urbanyi E, Herchenröder O, Spatz W, Volk B, Bohm N, Toniolo A, Neumann-Haefelin D, Schweizer M (1999) Sites of simian foamy virus persistence in naturally infected African green monkeys: latent provirus is ubiquitous, whereas viral replication is restricted to the oral mucosa. Virology 257:7–14PubMedCrossRefGoogle Scholar
  27. Flügel RM, Rethwilm A, Maurer B, Darai G (1987) Nucleotide sequence analysis of the env gene and its flanking regions of the human spumaretrovirus reveals two novel genes. EMBO J 6:2077–2084PubMedGoogle Scholar
  28. Garrett ED, He F, Bogerd HP, Cullen BR (1993) Transcriptional trans activators of human and simian foamy viruses contain a small, highly conserved activation domain. J Virol 67:6824–6827PubMedGoogle Scholar
  29. Giron ML, de The H, Saïb A (1998) An evolutionarily conserved splice generates a secreted env-Bet fusion protein during human foamy virus infection. J Virol 72:4906–4910PubMedGoogle Scholar
  30. Hatama S, Otake K, Ohta M, Kobayashi M, Imakawa K, Ikemoto A, Okuyama H, Mochizuki M, Miyazawa T, Tohya Y, Fujii Y, Takahashi E (2001) Reactivation of feline foamy virus from a chronically infected feline renal cell line by trichostatin A. Virology 283:315–323PubMedCrossRefGoogle Scholar
  31. He F, Blair WS, Fukushima J, Cullen BR (1996) The human foamy virus Bel-1 transcription factor is a sequence-specific DNA binding protein. J Virol 70:3902–3908PubMedGoogle Scholar
  32. He F, Sun JD, Garrett ED, Cullen BR (1993) Functional organization of the Bel-1 trans activator of human foamy virus. J Virol 67:1896–1904PubMedGoogle Scholar
  33. Heinkelein M, Dressler M, Jarmy G, Rammling M, Imrich H, Thurow J, Lindemann D, Rethwilm A. (2002) Improved primate foamy virus vectors and packaging constructs. J Virol 76:3774–3783PubMedCrossRefGoogle Scholar
  34. Heinkelein M, Thurow J, Dressler M, Imrich H, Neumann-Haefelin D, McClure MO, Rethwilm A (2000) Complex effects of deletions in the 5’ untranslated region of primate foamy virus on viral gene expression and RNA packaging. J Virol 74:3141–3148PubMedCrossRefGoogle Scholar
  35. Herchenröder O, Turek R, Neumann-Haefelin D, Rethwilm A, Schneider J (1995) Infectious proviral clones of chimpanzee foamy virus (SFVcpz) generated by long PCR reveal close functional relatedness to human foamy virus. Virology 214:685–689PubMedCrossRefGoogle Scholar
  36. Holzschu DL, Delaney MA, Renshaw RW, Casey JW (1998) The nucleotide sequence and spliced pol mRNA levels of the nonprimate spumavirus bovine foamy virus. J Virol 72:2177–2182PubMedGoogle Scholar
  37. Jordan I, Enssle J, Guttler E, Mauer B, Rethwilm A (1996) Expression of human foamy virus reverse transcriptase involves a spliced pol mRNA. Virology 224:314–319PubMedCrossRefGoogle Scholar
  38. Kang Y, Blair WS, Cullen BR (1998) Identification and functional characterization of a high-affinity Bel-1 DNA binding site located in the human foamy virus internal promoter. J Virol 72:504–511PubMedGoogle Scholar
  39. Kang Y, Bogerd HP, Cullen BR (2000) Analysis of cellular factors that mediate nuclear export of RNAs bearing the mason-pfizer monkey virus constitutive transport element. J Virol 74:5863–5871PubMedCrossRefGoogle Scholar
  40. Kang Y, Cullen BR (1998) Derivation and functional characterization of a consensus DNA binding sequence for the tas transcriptional activator of simian foamy virus type 1. J Virol 72:5502–5509PubMedGoogle Scholar
  41. Keller A, Garrett ED, Cullen BR (1992) The Bel-1 protein of human foamy virus activates human immunodeficiency virus type 1 gene expression via a novel DNA target site. J Virol 66:3946–3949PubMedGoogle Scholar
  42. Keller A, Partin KM, Löchelt M, Bannert H, Flügel RM, Cullen BR (1991) Characterization of the transcriptional trans activator of human foamy retrovirus. J Virol 65:2589–2594PubMedGoogle Scholar
  43. Kido K, Doerks A, Löchelt M, Flügel RM (2002) Identification and functional characterization of an intragenic DNA binding site for the spumaretroviral trans-activator in the human p57Kip2 gene. J Biol Chem 277:12032–12039PubMedCrossRefGoogle Scholar
  44. Kido K, Bannert H, Gronostajski RM, Flügel RM (2003) Bell-mediated trans-activation of the spumaretroviral internal promoter is repressed by nuclear factor I. J Biol Chem (in press)Google Scholar
  45. Lecellier CH, Saib A (2000) Foamy viruses: between retroviruses and pararetroviruses. Virology 271:1–8PubMedCrossRefGoogle Scholar
  46. Lecellier CH, Vermeulen W, Bachelerie F, Giron ML, Saib A. (2002) Intra-and inter-cellular trafficking of the foamy virus auxiliary bet protein. J Virol 76:3388–3394PubMedCrossRefGoogle Scholar
  47. Lee AH, Lee KJ, Kim S, Sung YC (1992) Transactivation of human immunodeficiency virus type 1 long terminal repeat-directed gene expression by the human foamy virus bell protein requires a specific DNA sequence. J Virol 66:3236–3240PubMedGoogle Scholar
  48. Lee, AH, Lee HY, Sung YC (1994a) The gene expression of human foamy virus does not require a post-transcriptional transactivator. Virology 204:409–413CrossRefGoogle Scholar
  49. Lee CW, Chang J, Lee KJ, Sung YC (1994b) The Bell protein of human foamy virus contains one positive and two negative control regions which regulate a distinct activation domain of 30 amino acids. J Virol 68:2708–2719Google Scholar
  50. Lee KJ, Lee AH, Sung YC (1993) Multiple positive and negative cis-acting elements that mediate transactivation by bell in the long terminal repeat of human foamy virus. J Virol 67:2317–2326PubMedGoogle Scholar
  51. Lindemann D, Rethwilm A (1998) Characterization of a human foamy virus 170-kilodalton Env-Bet fusion protein generated by alternative splicing. J Virol 72:4088–4094PubMedGoogle Scholar
  52. Linial M (2000) Why aren’t foamy viruses pathogenic? Trends Microbiol 8: 284–289 Linial ML (1999) Foamy viruses are unconventional retroviruses. J Virol 73:1747–1755PubMedCrossRefGoogle Scholar
  53. Linial ML (1999) Foamy viruses are unconventional retroviruses. J Virol 73:1747–1755PubMedGoogle Scholar
  54. Löchelt M, Aboud M, Flügel RM (1993a) Increase in the basal transcriptional activity of the human foamy virus internal promoter by the homologous long terminal repeat promoter in cis. Nucleic Acids Res 21:4226–4230CrossRefGoogle Scholar
  55. Löchelt M, Flügel RM (1995) The molecular biology of primate spumaviruses. In Levy JA (ed.) The Retroviridae vol. 4. Plenum Press, New YorkGoogle Scholar
  56. Löchelt M, Flügel RM (1996) The human foamy virus pol gene is expressed as a Pro-Pol polyprotein and not as a Gag-Pol fusion protein. J Virol 70:1033–1040PubMedGoogle Scholar
  57. Löchelt M, Flügel RM, Aboud M (1994) The human foamy virus internal promoter directs the expression of the functional Bel 1 transactivator and Bet protein early after infection. J Virol 68:638–645PubMedGoogle Scholar
  58. Löchelt M, Muranyi W, Flügel RM (1993b) Human foamy virus genome possesses an internal, Bel-l-dependent and functional promoter. Proc Nail Acad Sci U S A 90:7317–7321CrossRefGoogle Scholar
  59. Löchelt M, Yu SF, Linial ML, Flügel RM (1995) The human foamy virus internal promoter is required for efficient gene expression and infectivity. Virology 206:601–610PubMedCrossRefGoogle Scholar
  60. Löchelt M, Zentgraf H, Flügel RM (1991) Construction of an infectious DNA clone of the full-length human spumaretrovirus genome and mutagenesis of the bel 1 gene. Virology 184:43–54PubMedCrossRefGoogle Scholar
  61. Maurer B, Serfling E, ter Meulen V, Rethwilm A (1991) Transcription factor AP-1 modulates the activity of the human foamy virus long terminal repeat. J Virol 65:6353–6357PubMedGoogle Scholar
  62. Meiering CD, Rubio C, May C, Linial ML (2001) Cell-type-specific regulation of the two foamy virus promoters. J Virol 75:6547–6557PubMedCrossRefGoogle Scholar
  63. Meiering CD, Linial ML (2001) Historical perspective of foamy virus epidemiology and infection. Clin Microbiol Rev 14:165–176Google Scholar
  64. Meiering CD, Linial ML (2002) Reactivation of a complex retrovirus is controlled by a molecular switch and is inhibited by a viral protein. Proc Natl Acad Sci USA 99:15130–15135PubMedCrossRefGoogle Scholar
  65. Meiering CD, Linial ML (2003) The promyelocytic leukemia protein does not mediate foamyvirus latency in vitro. J Virol 77:2207–2213PubMedCrossRefGoogle Scholar
  66. Mergia A (1994) Simian foamy virus type 1 contains a second promoter located at the 3’ end of the env gene. Virology 199:219–222PubMedCrossRefGoogle Scholar
  67. Mergia A, Pratt-Lowe E, Shaw KE, Renshaw-Gegg LW, Luciw PA (1992) cis-acting regulatory regions in the long terminal repeat of simian foamy virus type 1. J Virol 66:251–257PubMedGoogle Scholar
  68. Mergia A, Renshaw-Gegg LW, Stout MW, Renne R, Herchenroeder 0 (1993) Functional domains of the simian foamy virus type 1 transcriptional transactivator (Taf). J Virol 67:4598–4604PubMedGoogle Scholar
  69. Mergia A, Shaw KE, Pratt-Lowe E, Barry PA, Luciw PA (1990) Simian foamy virus type 1 is a retrovirus which encodes a transcriptional transactivator. J Virol 64:3598–3604PubMedGoogle Scholar
  70. Mergia A, Shaw KE, Pratt-Lowe E, Barry PA, Luciw PA (1991) Identification of the simian foamy virus transcriptional transactivator gene (taf). J Virol 65:2903–2909PubMedGoogle Scholar
  71. Moebes A, Enssle J, Bieniasz PD, Heinkelein M, Lindemann D, Bock M, McClure MO, Rethwilm A (1997) Human foamy virus reverse transcription that occurs late in the viral replication cycle. J Virol 71:7305–7311PubMedGoogle Scholar
  72. Muranyi W, Flügel RM (1991) Analysis of splicing patterns of human spumaretrovirus by polymerase chain reaction reveals complex RNA structures. J Virol 65:727–735PubMedGoogle Scholar
  73. Park J, Mergia A (2000) Mutational analysis of the 5’ leader region of simian foamy virus type 1. Virology 274:203–212.PubMedCrossRefGoogle Scholar
  74. Regad T, Saib A, Lallemand-Breitenbach V, Pandolfi PP, de The H, Chelbi-Alix MK (2001) PML mediates the interferon-induced antiviral state against a complex retrovirus via its association with the viral transactivator. EMBO J 20:3495–3505PubMedCrossRefGoogle Scholar
  75. Renne R, Fleps U, Luciw PA, Neumann-Haefelin D (1996) Transactivation of the two promoters of SFV-3 by different mechanisms. Virology 221:362–367PubMedCrossRefGoogle Scholar
  76. Renne R, Mergia A, Renshaw-Gegg LW, Neumann-Haefelin D, Luciw PA (1993) Regulatory elements in the long terminal repeat (LTR) of simian foamy virus type 3 (SFV-3). Virology 192:365–369PubMedCrossRefGoogle Scholar
  77. Renshaw RW, Casey JW (1994a) Analysis of the 5’ long terminal repeat of bovine syncytial virus. Gene 141:221–224CrossRefGoogle Scholar
  78. Renshaw RW, Casey JW (1994b) Transcriptional mapping of the 3’ end of the bovine syncytial virus genome. J Virol 68:1021–1028Google Scholar
  79. Rethwilm A (1995) Regulation of foamy virus gene expression. Curr Top Microbiol Immunol 193:1–24PubMedCrossRefGoogle Scholar
  80. Rethwilm A, Erlwein O, Baunach G, Maurer B, ter Meulen V (1991) The transcriptional transactivator of human foamy virus maps to the bel 1 genomic region. Proc Natl Acad Sci U S A 88:941–945PubMedCrossRefGoogle Scholar
  81. Russell RA, Zeng Y, Erlwein O, Cullen BR, McClure MO (2001) The R region found in the human foamy virus long terminal repeat is critical for both Gag and Pol protein expression. J Virol 75:6817–6824PubMedCrossRefGoogle Scholar
  82. Saib A, Neves M, Giron ML, Guillemin MC, Valla J, Perks J, Canivet M (1997) Longterm persistent infection of domestic rabbits by the human foamy virus. Virology 228:263–268PubMedCrossRefGoogle Scholar
  83. Saib A, Perks J, de The H (1993) A defective human foamy provirus generated by pregenome splicing. EMBO J 12:4439–4444PubMedGoogle Scholar
  84. Schenk T, Enssle J, Fischer N, Rethwilm A (1999) Replication of a foamy virus mutant with a constitutively active U3 promoter and deleted accessory genes. J Gen Virol 80:1591–1598PubMedGoogle Scholar
  85. Schliephake AW, Rethwilm A (1994) Nuclear localization of foamy virus Gag precursor protein. J Virol 68:4946–4954PubMedGoogle Scholar
  86. Schmidt M, Herchenröder O, Heeney J, Rethwilm A (1997) Long terminal repeat U3 length polymorphism of human foamy virus. Virology 230:167–178PubMedCrossRefGoogle Scholar
  87. Schwantes A, Ortlepp I, Löchelt M (2002) Construction and functional characterization of feline foamy virus-based retroviral vectors. Virology 301:53–63PubMedCrossRefGoogle Scholar
  88. Schwartz S, Felber BK, Pavlakis GN (1992) Distinct RNA sequences in the gag region of human immunodeficiency virus type 1 decrease RNA stability and inhibit expression in the absence of Rev protein. J Virol 66:150–159Google Scholar
  89. Schweizer M, Fleps U, Jackie A, Renne R, Turek R, Neumann-Haefelin D (1993) Simian foamy virus type 3 (SFV-3) in latently infected Vero cells: reactivation by demethylation of proviral DNA. Virology 192:663–666PubMedCrossRefGoogle Scholar
  90. Tobaly-Tapiero J, Bittoun P, Neves M, Guillemin MC, Lecellier CH, Puvion-Dutilleul F, Gicquel B, Zientara S, Giron ML, de The H, Saib A (2000) Isolation and characterization of an equine foamy virus. J Virol 74:4064–4073PubMedCrossRefGoogle Scholar
  91. Venkatesh, LK, Chinnadurai G (1993) The carboxy-terminal transcription enhancement region of the human spumaretrovirus transactivator contains discrete determinants of the activator function. J Virol 67:3868–3876.PubMedGoogle Scholar
  92. Venkatesh LK, Theodorakis PA, Chinnadurai G (1991) Distinct cis-acting regions in U3 regulate trans-activation of the human spumaretrovirus long terminal repeat by the viral bell gene product. Nucleic Acids Res 19:3661–3666PubMedCrossRefGoogle Scholar
  93. Venkatesh LK, Yang C, Theodorakis PA, Chinnadurai G (1993) Functional dissection of the human spumaretrovirus transactivator identifies distinct classes of dominant-negative mutants. J Virol 67:161–169PubMedGoogle Scholar
  94. Wagner A, Doerks A, Aboud M, Alonso A, Tokino T, Flügel RM, Löchelt M (2000) Induction of cellular genes is mediated by the Bell transactivator in foamy virus-infected human cells. J Virol 74:4441–4447PubMedCrossRefGoogle Scholar
  95. Winkler I, Bodem J, Haas L, Zemba M, Delius H, Flower R, Flügel RM, Löchelt M (1997) Characterization of the genome of feline foamy virus and its proteins shows distinct features different from those of primate spumaviruses. J Virol 71:6727–6741PubMedGoogle Scholar
  96. Winkler IG, Flügel RM, Löchelt M, Flower RL (1998) Detection and molecular characterisation of feline foamy virus serotypes in naturally infected cats. Virology 247:144–151PubMedCrossRefGoogle Scholar
  97. Winkler IG, Löchelt M, Flower RL (1999) Epidemiology of feline foamy virus and feline immunodeficiency virus infections in domestic and feral cats: a seroepidemiological study. J Clin Microbiol 37:2848–2851PubMedGoogle Scholar
  98. Wodrich H, Bohne J, Gumz E, Welker R, Krausslich HG. (2001) A new RNA element located in the coding region of a murine endogenous retrovirus can functionally replace the Rev/Rev-responsive element system in human immunodeficiency virus type 1 Gag expression. J. Virol 75:10670–10682PubMedCrossRefGoogle Scholar
  99. Yang P, Zemba M, Aboud M, Flügel RM, Löchelt M (1997) Deletion analysis of both the long terminal repeat and the internal promoters of the human foamy virus. Virus Genes 15:17–23PubMedCrossRefGoogle Scholar
  100. Yoshida M (1997) Howard Temin memorial lectureship. Molecular biology of HTLV- 1: deregulation of host cell gene expression and cell cycle. Leukemia 11:14–15CrossRefGoogle Scholar
  101. Yu SF, Baldwin DN, Gwynn SR, Yendapalli S, Linial ML (1996a) Human foamy virus replication: a pathway distinct from that of retroviruses and hepadnaviruses. Science 271:1579–1582CrossRefGoogle Scholar
  102. Yu SF, Edelmann K, Strong RK, Moebes A, Rethwilm A, Linial ML (1996b) The carboxyl terminus of the human foamy virus Gag protein contains separable nucleic acid binding and nuclear transport domains. J Virol 70:8255–8262Google Scholar
  103. Yu SF, Linial ML (1993) Analysis of the role of the bel and bet open reading frames of human foamy virus by using a new quantitative assay. J Virol 67:6618–6624PubMedGoogle Scholar
  104. Zou JX, Luciw PA (1996) The transcriptional transactivator of simian foamy virus 1 binds to a DNA target element in the viral internal promoter. Proc Natl Acad Sci USA 93:326–330PubMedCrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  1. 1.Abteilung Retrovirale GenexpressionAngewandte Tumorvirologie, Deutsches KrebsforschungszentrumHeidelbergGermany

Personalised recommendations