1887

Abstract

Plant pararetroviruses, such as caulimoviruses, and animal retroviruses have in common the presence of a highly conserved arrangement of cysteines and a histidine in the precursor of the capsid protein. The composition of these amino acids resembles a zinc finger element, a structure that is common to a class of eukaryotic proteins that regulate gene expression. The role of the putative zinc finger in the life-cycle of caulimoviruses was investigated by introducing specific mutations in the coat protein coding region of a cloned and infectious form of figwort mosaic virus, a caulimovirus. This mutated viral genome, which no longer encoded the conserved cysteine and histidine residues, was not infectious in plants. Transient expression assays in protoplasts showed that expression of a reporter gene inserted at different places in the genome was not detectably influenced by the coat protein or its putative zinc finger. It appears that the zinc finger-like element of caulimoviruses is not involved in the regulation of gene expression. These observations support a model which predicts a function of the zinc finger in specific recognition and packaging of viral RNA into virions prior to reverse transcription.

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1993-04-01
2021-10-21
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References

  1. Aldovini A., Young R. A. 1990; Mutations of RNA and protein sequences involved in human immunodeficiency virus type 1 packaging result in production of noninfectious virus. Journal of Virology 64:1920–1926
    [Google Scholar]
  2. Berg J. M. 1986; Potential metal-binding domains in nucleic acid binding proteins. Science 232:485–487
    [Google Scholar]
  3. Bess J. W., Powell P. J., Issaq H. J., Schumack L. J., Grimes M. K., Henderson L. E., Arthur L. O. 1992; Tightly bound zinc in human immunodeficiency virus type 1, human T-cell-leukemia virus type 1, and other retroviruses. Journal of Virology 66:840–847
    [Google Scholar]
  4. Covey S. N. 1986; Amino acid sequence homology in gag region of reverse transcribing elements and the coat protein gene of cauliflower mosaic virus. Nucleic Acids Research 14:623–633
    [Google Scholar]
  5. Daubert S., Shepherd R. J., Gardner R. C. 1983; Insertional mutagenesis of the cauliflower mosaic virus genome. Gene 25:201–208
    [Google Scholar]
  6. de Rocquigny H., Gabus C., Vincent A., Fournie-Zaluski M. C., Roques B., Darlix J. 1992; Viral RNA annealing activities of human immunodeficiency virus type 1 nucleocapsid protein require only peptide domains outside the zinc fingers. Proceedings of the National Academy of Sciences, U.S.A. 89:6472–6476
    [Google Scholar]
  7. Futterer J., FIohn T. 1987; Involvement of nucleocapsids in reverse transcription: a general phenomenon?. Trends in Biochemical Sciences 12:92–95
    [Google Scholar]
  8. Gorelick R. J., Henderson L. E., Hanser J. P., Rein A. 1988; Point mutants of Moloney murine leukemia virus that fail to package viral RNA: Evidence for specific RNA recognition by a “zinc finger-like” protein sequence. Proceedings of the National Academy of Sciences, U.S.A. 85:8420–8424
    [Google Scholar]
  9. Gowda S., Wu F. C., Scholthof H. B., Shepherd R. J. 1989; Gene VI of figwort mosaic virus (caulimovirus group) functions in post-transcriptional expression of genes on the full-length RNA transcript. Proceedings of the National Academy of Sciences, U.S.A. 86:9203–9207
    [Google Scholar]
  10. Gowda S., Wu F. C., Scholthof H. B., Shepherd R. J. 1990; Gene VI of figwort mosaic virus activates expression of internal cistrons of the full-length polycistronic RNA transcript. In Viral Genes and Plant Pathogenesis pp 79–88 Edited by Pirone T. P., Shaw J. G. New York: Springer-Verlag;
    [Google Scholar]
  11. Gowda S., Scholthof H. B., Wu F. C., Shepherd R. J. 1991; Requirement of gene VII in cis for the expression of downstream genes on the major transcript of figwort mosaic virus. Virology 185:867–871
    [Google Scholar]
  12. Green L. M., Berg J. M. 1989; A retroviral Cys-Xaa2-Cys-Xaa4-His-Xaa4-Cys peptide binds metal ions: spectroscopic studies and a proposed three-dimensional structure. Proceedings of the National Academy of Sciences, U.S.A. 86:4047–4051
    [Google Scholar]
  13. Jefferson T. 1987; saying chimeric genes in plants: the GUS gene fusion system. Plant Molecular Biology Reporter 5:387–405
    [Google Scholar]
  14. Jentoft J. E., Smith L. M., Fu X., Johnson M., Leis J. 1988; Conserved cysteine and histidine residues of the avian myeloblastosis virus nucleocapsid protein are essential for viral replication but are not “zinc-binding fingers”. Proceedings of the National Academy of Sciences, U.S.A. 85:7094–7098
    [Google Scholar]
  15. Kunkel T. A. 1985; Rapid and efficient site-specific mutagenesis without phenotypic selection. Proceedings of the National Academy of Sciences, U.S.A. 82:488–492
    [Google Scholar]
  16. Lockhart B. EL. 1990; Evidence for a double-stranded circular DNA genome in a second group of plant viruses. Phytopathology 80:127–131
    [Google Scholar]
  17. Marsh L. E., Guilfoyle T. J. 1987; Cauliflower mosaic virus replication intermediates are encapsidated into virion-like particles. Virology 161:129–137
    [Google Scholar]
  18. Mazzolini L., Dabos P., Constantin S., Yot P. 1989; Further evidence that viroplasms are the site of cauliflower mosaic virus genome replication by reverse transcription during viral infection. Journal of General Virology 70:3439–3449
    [Google Scholar]
  19. Prats A. C., Sarih L., Gabus C., Litvak S., Keith G., Darlix J. 1988; Small finger protein of avian and murine retroviruses has nucleic acid annealing activity and positions the replication primer tRNA onto genomic RNA. EMBO Journal 1:1777–1783
    [Google Scholar]
  20. Prats A. C., Roy C., Wang P., Wang P., Housset V., Gabus V., Paoletti C., Darlix J. L. 1990; Cis elements and irans-acting factors involved in dimer formation of murine leukemia virus RNA. Journal of Virology 64:774–783
    [Google Scholar]
  21. Prats A. C., Housset V., De Billy G., Corville F., Prats H., Roques B. 1991; Viral RNA annealing activities of the nucleocapsid protein of Moloney murine leukemia virus are zinc independent. Nucleic Acids Research 19:3533–3541
    [Google Scholar]
  22. Richins R. D., Scholthof H. B. 1987; Sequence of figwort mosaic virus DNA (caulimovirus group). Nucleic Acids Research 15:8451–8466
    [Google Scholar]
  23. Schardl C. L., Byrd A. D., Benzion G., Altschuler M. A., Hildebrand D. F., Hunt A. G. 1987; Design and construction of a versatile system for the expression of foreign genes in plants. Gene 61:1–11
    [Google Scholar]
  24. Scholthof H. B. 1990 Regulatory mechanisms and elements involved in gene expression of figwort mosaic virus, a caulimovirus University of Kentucky: Ph.D. thesis;
    [Google Scholar]
  25. Scholthof H. B., Wu F. C., Richins R. D., Shepherd R. J. 1991; A naturally occurring deletion mutant of figwort mosaic virus (caulimovirus) is generated by RNA splicing. Virology 184:290–298
    [Google Scholar]
  26. Scholthof H. B., Gowda S., Wu F. C., Shepherd R. J. 1992a; The full-length transcript of a caulimovirus is a polycistronic mRNA whose genes are trans activated by the product of gene VI. Journal of Virology 66:3131–3139
    [Google Scholar]
  27. Scholthof H. B., Wu F. C., Gowda S., Shepherd R. J. 1992b; Regulation of caulimovirus gene expression and the involvement of ds-acting elements on both viral transcripts. Virology 190:403–412
    [Google Scholar]
  28. Seeger C., Maragos J. M. 1991; Identification of a signal necessary for initiation of reverse transcription of the hepadnavirus genome. Journal of Virology 65:5190–5195
    [Google Scholar]
  29. Spratt B. G., Hedge P. J., te Heesen S., Edelman A., Broome-Smith J. K. 1986; Kanamycin-resistant vectors that are analogues of plasmids pUC8, pUC9, pEMBL8 and pEMBL9. Gene 41:337–342
    [Google Scholar]
  30. Temin H. M. 1985; Reverse transcription in the eukaryotic genome: retroviruses, pararetroviruses, retrotransposons, and retrotran-scripts. Molecular Biology and Evolution 2:455–168
    [Google Scholar]
  31. Torruella M., Gordon K., Hohn T. 1989; Cauliflower mosaic virus produces an aspartic proteinase to cleave its polyproteins. EMBO Journal 8:2819–2825
    [Google Scholar]
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