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. 1986 Mar;57(3):826–832. doi: 10.1128/jvi.57.3.826-832.1986

Bovine leukemia virus protease: purification, chemical analysis, and in vitro processing of gag precursor polyproteins.

Y Yoshinaka, I Katoh, T D Copeland, G W Smythers, S Oroszlan
PMCID: PMC252811  PMID: 3005629

Abstract

Bovine leukemia virus protease was purified to homogeneity and assayed by using murine leukemia virus Pr65gag, a polyprotein precursor of the viral core structural proteins, as the substrate. A chemical analysis of the protease, including an amino acid composition and NH2- and COOH-terminal amino acid sequence analysis, revealed that it has an Mr of 14,000 and is encoded by a segment of the viral RNA located between the gag gene and the putative reverse transcriptase gene. As expected from the nucleotide sequence data (Rice et al., Virology 142:357-377, 1985), the reading frame for the protease is different from both the gag and reverse transcriptase reading frames. The 5' end of the protease open reading frame extends 38 codons upstream from the codon for the NH2-terminal residue of the mature viral protease and overlaps the gag open reading frame by 7 codons. The 3' end of the protease open reading frame extends 26 codons beyond the codon for the COOH-terminal residue of the mature protease and overlaps 8 codons of the reverse transcriptase open reading frame. Several lines of evidence, such as protein mapping of the gag polyprotein precursor, the characteristic structure of the mRNA, and promotion of the synthesis of a gag polyprotein precursor by lysine tRNA in vitro, suggest that the protease could be translated by frameshift suppression of the gag termination codon. In vitro synthesized bovine leukemia virus gag-related polyproteins were cleaved by the protease into fragments which were the same size as the known components of bovine leukemia virus, suggesting that the specificity of cleavage catalyzed in vitro by the purified protease is the same as the specificity of cleavage found in the virus.

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Selected References

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  1. Atkins J. F., Gesteland R. F., Reid B. R., Anderson C. W. Normal tRNAs promote ribosomal frameshifting. Cell. 1979 Dec;18(4):1119–1131. doi: 10.1016/0092-8674(79)90225-3. [DOI] [PubMed] [Google Scholar]
  2. Chamberlain J. P. Fluorographic detection of radioactivity in polyacrylamide gels with the water-soluble fluor, sodium salicylate. Anal Biochem. 1979 Sep 15;98(1):132–135. doi: 10.1016/0003-2697(79)90716-4. [DOI] [PubMed] [Google Scholar]
  3. Copeland T. D., Morgan M. A., Oroszlan S. Complete amino acid sequence of the nucleic acid-binding protein of bovine leukemia virus. FEBS Lett. 1983 May 30;156(1):37–40. doi: 10.1016/0014-5793(83)80243-9. [DOI] [PubMed] [Google Scholar]
  4. Fox T. D., Weiss-Brummer B. Leaky +1 and -1 frameshift mutations at the same site in a yeast mitochondrial gene. Nature. 1980 Nov 6;288(5786):60–63. doi: 10.1038/288060a0. [DOI] [PubMed] [Google Scholar]
  5. Gazdar A. F., Phillips L. A., Sarma P. S., Peebles P. T., Chopra H. C. Presence of sarcoma genome in a "non-infectious" mammalian virus. Nat New Biol. 1971 Nov 17;234(46):69–72. doi: 10.1038/newbio234069a0. [DOI] [PubMed] [Google Scholar]
  6. Ghysdael J., Kettmann R., Burny A. Translation of bovine leukemia virus virion RNAs in heterologous protein-synthesizing systems. J Virol. 1979 Mar;29(3):1087–1098. doi: 10.1128/jvi.29.3.1087-1098.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Henderson L. E., Copeland T. D., Oroszlan S. Separation of amino acid phenylthiohydantoins by high-performance liquid chromatography on phenylalkyl support. Anal Biochem. 1980 Feb;102(1):1–7. doi: 10.1016/0003-2697(80)90307-3. [DOI] [PubMed] [Google Scholar]
  8. Hewick R. M., Hunkapiller M. W., Hood L. E., Dreyer W. J. A gas-liquid solid phase peptide and protein sequenator. J Biol Chem. 1981 Aug 10;256(15):7990–7997. [PubMed] [Google Scholar]
  9. Kohno T., Roth J. R. A Salmonella frameshift suppressor that acts at runs of A residues in the messenger RNA. J Mol Biol. 1978 Nov 25;126(1):37–52. doi: 10.1016/0022-2836(78)90278-4. [DOI] [PubMed] [Google Scholar]
  10. 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]
  11. Oroszlan S., Copeland T. D., Henderson L. E., Stephenson J. R., Gilden R. V. Amino-terminal sequence of bovine leukemia virus major internal protein: homology with mammalian type C virus p30 structural proteins. Proc Natl Acad Sci U S A. 1979 Jun;76(6):2996–3000. doi: 10.1073/pnas.76.6.2996. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Oroszlan S., Copeland T. D. Primary structure and processing of gag and env gene products of human T-cell leukemia viruses HTLV-ICR and HTLV-IATK. Curr Top Microbiol Immunol. 1985;115:221–233. doi: 10.1007/978-3-642-70113-9_14. [DOI] [PubMed] [Google Scholar]
  13. Oroszlan S., Henderson L. E., Stephenson J. R., Copeland T. D., Long C. W., Ihle J. N., Gilden R. V. Amino- and carboxyl-terminal amino acid sequences of proteins coded by gag gene of murine leukemia virus. Proc Natl Acad Sci U S A. 1978 Mar;75(3):1404–1408. doi: 10.1073/pnas.75.3.1404. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Oroszlan S., Sarngadharan M. G., Copeland T. D., Kalyanaraman V. S., Gilden R. V., Gallo R. C. Primary structure analysis of the major internal protein p24 of human type C T-cell leukemia virus. Proc Natl Acad Sci U S A. 1982 Feb;79(4):1291–1294. doi: 10.1073/pnas.79.4.1291. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Poiesz B. J., Ruscetti F. W., Gazdar A. F., Bunn P. A., Minna J. D., Gallo R. C. Detection and isolation of type C retrovirus particles from fresh and cultured lymphocytes of a patient with cutaneous T-cell lymphoma. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7415–7419. doi: 10.1073/pnas.77.12.7415. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Rice N. R., Stephens R. M., Burny A., Gilden R. V. The gag and pol genes of bovine leukemia virus: nucleotide sequence and analysis. Virology. 1985 Apr 30;142(2):357–377. doi: 10.1016/0042-6822(85)90344-7. [DOI] [PubMed] [Google Scholar]
  17. Rice N. R., Stephens R. M., Couez D., Deschamps J., Kettmann R., Burny A., Gilden R. V. The nucleotide sequence of the env gene and post-env region of bovine leukemia virus. Virology. 1984 Oct 15;138(1):82–93. doi: 10.1016/0042-6822(84)90149-1. [DOI] [PubMed] [Google Scholar]
  18. Sagata N., Yasunaga T., Tsuzuku-Kawamura J., Ohishi K., Ogawa Y., Ikawa Y. Complete nucleotide sequence of the genome of bovine leukemia virus: its evolutionary relationship to other retroviruses. Proc Natl Acad Sci U S A. 1985 Feb;82(3):677–681. doi: 10.1073/pnas.82.3.677. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Schultz A. M., Copeland T. D., Oroszlan S. The envelope proteins of bovine leukemia virus: purification and sequence analysis. Virology. 1984 Jun;135(2):417–427. doi: 10.1016/0042-6822(84)90197-1. [DOI] [PubMed] [Google Scholar]
  20. Schwartz D. E., Tizard R., Gilbert W. Nucleotide sequence of Rous sarcoma virus. Cell. 1983 Mar;32(3):853–869. doi: 10.1016/0092-8674(83)90071-5. [DOI] [PubMed] [Google Scholar]
  21. Seiki M., Hattori S., Hirayama Y., Yoshida M. Human adult T-cell leukemia virus: complete nucleotide sequence of the provirus genome integrated in leukemia cell DNA. Proc Natl Acad Sci U S A. 1983 Jun;80(12):3618–3622. doi: 10.1073/pnas.80.12.3618. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Wray W., Boulikas T., Wray V. P., Hancock R. Silver staining of proteins in polyacrylamide gels. Anal Biochem. 1981 Nov 15;118(1):197–203. doi: 10.1016/0003-2697(81)90179-2. [DOI] [PubMed] [Google Scholar]
  23. Yoshida M., Miyoshi I., Hinuma Y. Isolation and characterization of retrovirus from cell lines of human adult T-cell leukemia and its implication in the disease. Proc Natl Acad Sci U S A. 1982 Mar;79(6):2031–2035. doi: 10.1073/pnas.79.6.2031. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Yoshinaka Y., Katoh I., Copeland T. D., Oroszlan S. Murine leukemia virus protease is encoded by the gag-pol gene and is synthesized through suppression of an amber termination codon. Proc Natl Acad Sci U S A. 1985 Mar;82(6):1618–1622. doi: 10.1073/pnas.82.6.1618. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Yoshinaka Y., Katoh I., Copeland T. D., Oroszlan S. Translational readthrough of an amber termination codon during synthesis of feline leukemia virus protease. J Virol. 1985 Sep;55(3):870–873. doi: 10.1128/jvi.55.3.870-873.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Yoshinaka Y., Luftig R. B. Properties of a P70 proteolytic factor of murine leukemia viruses. Cell. 1977 Nov;12(3):709–719. doi: 10.1016/0092-8674(77)90271-9. [DOI] [PubMed] [Google Scholar]
  27. Yoshinaka Y., Luftig R. B. p65 of Gazdar murine sarcoma viruses contains antigenic determinants from all four of the murine leukemia virus (MuLV) gag polypeptides (p15, p12, p30, and p10) and can be cleaved in vitro by the MuLV proteolytic activity. Virology. 1982 Apr 30;118(2):380–388. doi: 10.1016/0042-6822(82)90357-9. [DOI] [PubMed] [Google Scholar]
  28. Yoshinaka Y., Oroszlan S. Bovine leukemia virus post-envelope gene coded protein: evidence for expression in natural infection. Biochem Biophys Res Commun. 1985 Aug 30;131(1):347–354. doi: 10.1016/0006-291x(85)91809-1. [DOI] [PubMed] [Google Scholar]

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