Skip to main content
PMC home page
Journal of Virology logoLink to Journal of Virology
. 1995 Jun;69(6):3407–3419. doi: 10.1128/jvi.69.6.3407-3419.1995

The spacer peptide between human immunodeficiency virus capsid and nucleocapsid proteins is essential for ordered assembly and viral infectivity.

H G Kräusslich 1, M Fäcke 1, A M Heuser 1, J Konvalinka 1, H Zentgraf 1
PMCID: PMC189053  PMID: 7745687

Abstract

Morphogenesis of retroviruses involves ordered assembly of the structural Gag- and Gag-Pol polyproteins, with subsequent budding from the plasma membrane and proteolytic cleavage by the viral proteinase (PR). Two cleavage sites exist between the capsid (CA) and nucleocapsid (NC) domains of the human immunodeficiency virus (HIV) type 1 Gag polyprotein which are separated by a 14-amino-acid spacer peptide of unknown function. To analyze the role of the two cleavage sites and the spacer peptide, both sites were individually mutated and a deletion mutation that precisely removes the spacer peptide was constructed. Following transfection of proviral DNA carrying the point mutations, mutant polyproteins were synthesized and assembled like wild-type polyprotein, and release of particles was not significantly altered. Both mutations abolished cleavage at the respective site and reduced or abolished viral infectivity. Deletion of the spacer peptide severely affected ordered assembly and reduced particle release. The extracellular particles that were released exhibited normal density but were heterogeneous in size. Electron micrographs revealed large electron-dense plaques underneath the plasma membrane of transfected cells which appeared like confluent ribonucleoprotein complexes arrested early in the budding process. Extracellular particles exhibited very aberrant and heterogeneous morphology and were incapable of inducing viral spread. These particles may correspond to membrane vesicles sequestered by the rigid structures underneath the cell membrane and not released by a regular budding process.

Full Text

The Full Text of this article is available as a PDF (2.3 MB).

Selected References

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

  1. Adachi A., Gendelman H. E., Koenig S., Folks T., Willey R., Rabson A., Martin M. A. Production of acquired immunodeficiency syndrome-associated retrovirus in human and nonhuman cells transfected with an infectious molecular clone. J Virol. 1986 Aug;59(2):284–291. doi: 10.1128/jvi.59.2.284-291.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Bryant M., Ratner L. Myristoylation-dependent replication and assembly of human immunodeficiency virus 1. Proc Natl Acad Sci U S A. 1990 Jan;87(2):523–527. doi: 10.1073/pnas.87.2.523. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Chazal N., Carrière C., Gay B., Boulanger P. Phenotypic characterization of insertion mutants of the human immunodeficiency virus type 1 Gag precursor expressed in recombinant baculovirus-infected cells. J Virol. 1994 Jan;68(1):111–122. doi: 10.1128/jvi.68.1.111-122.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Craven R. C., Leure-duPree A. E., Erdie C. R., Wilson C. B., Wills J. W. Necessity of the spacer peptide between CA and NC in the Rous sarcoma virus gag protein. J Virol. 1993 Oct;67(10):6246–6252. doi: 10.1128/jvi.67.10.6246-6252.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Dougherty W. G., Semler B. L. Expression of virus-encoded proteinases: functional and structural similarities with cellular enzymes. Microbiol Rev. 1993 Dec;57(4):781–822. doi: 10.1128/mr.57.4.781-822.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Ehrlich L. S., Agresta B. E., Carter C. A. Assembly of recombinant human immunodeficiency virus type 1 capsid protein in vitro. J Virol. 1992 Aug;66(8):4874–4883. doi: 10.1128/jvi.66.8.4874-4883.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Elder J. H., Schnölzer M., Hasselkus-Light C. S., Henson M., Lerner D. A., Phillips T. R., Wagaman P. C., Kent S. B. Identification of proteolytic processing sites within the Gag and Pol polyproteins of feline immunodeficiency virus. J Virol. 1993 Apr;67(4):1869–1876. doi: 10.1128/jvi.67.4.1869-1876.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Erickson-Viitanen S., Manfredi J., Viitanen P., Tribe D. E., Tritch R., Hutchison C. A., 3rd, Loeb D. D., Swanstrom R. Cleavage of HIV-1 gag polyprotein synthesized in vitro: sequential cleavage by the viral protease. AIDS Res Hum Retroviruses. 1989 Dec;5(6):577–591. doi: 10.1089/aid.1989.5.577. [DOI] [PubMed] [Google Scholar]
  9. Franke W. W., Lüder M. R., Kartenbeck J., Zerban H., Keenan T. W. Involvement of vesicle coat material in casein secretion and surface regeneration. J Cell Biol. 1976 Apr;69(1):173–195. doi: 10.1083/jcb.69.1.173. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Gelderblom H. R. Assembly and morphology of HIV: potential effect of structure on viral function. AIDS. 1991 Jun;5(6):617–637. [PubMed] [Google Scholar]
  11. Gelderblom H. R., Hausmann E. H., Ozel M., Pauli G., Koch M. A. Fine structure of human immunodeficiency virus (HIV) and immunolocalization of structural proteins. Virology. 1987 Jan;156(1):171–176. doi: 10.1016/0042-6822(87)90449-1. [DOI] [PubMed] [Google Scholar]
  12. Gheysen D., Jacobs E., de Foresta F., Thiriart C., Francotte M., Thines D., De Wilde M. Assembly and release of HIV-1 precursor Pr55gag virus-like particles from recombinant baculovirus-infected insect cells. Cell. 1989 Oct 6;59(1):103–112. doi: 10.1016/0092-8674(89)90873-8. [DOI] [PubMed] [Google Scholar]
  13. Greber U. F., Singh I., Helenius A. Mechanisms of virus uncoating. Trends Microbiol. 1994 Feb;2(2):52–56. doi: 10.1016/0966-842x(94)90126-0. [DOI] [PubMed] [Google Scholar]
  14. Göttlinger H. G., Dorfman T., Sodroski J. G., Haseltine W. A. Effect of mutations affecting the p6 gag protein on human immunodeficiency virus particle release. Proc Natl Acad Sci U S A. 1991 Apr 15;88(8):3195–3199. doi: 10.1073/pnas.88.8.3195. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Göttlinger H. G., Sodroski J. G., Haseltine W. A. Role of capsid precursor processing and myristoylation in morphogenesis and infectivity of human immunodeficiency virus type 1. Proc Natl Acad Sci U S A. 1989 Aug;86(15):5781–5785. doi: 10.1073/pnas.86.15.5781. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Harada S., Koyanagi Y., Yamamoto N. Infection of HTLV-III/LAV in HTLV-I-carrying cells MT-2 and MT-4 and application in a plaque assay. Science. 1985 Aug 9;229(4713):563–566. doi: 10.1126/science.2992081. [DOI] [PubMed] [Google Scholar]
  17. Henderson L. E., Benveniste R. E., Sowder R., Copeland T. D., Schultz A. M., Oroszlan S. Molecular characterization of gag proteins from simian immunodeficiency virus (SIVMne). J Virol. 1988 Aug;62(8):2587–2595. doi: 10.1128/jvi.62.8.2587-2595.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Henderson L. E., Bowers M. A., Sowder R. C., 2nd, Serabyn S. A., Johnson D. G., Bess J. W., Jr, Arthur L. O., Bryant D. K., Fenselau C. Gag proteins of the highly replicative MN strain of human immunodeficiency virus type 1: posttranslational modifications, proteolytic processings, and complete amino acid sequences. J Virol. 1992 Apr;66(4):1856–1865. doi: 10.1128/jvi.66.4.1856-1865.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Henderson L. E., Sowder R. C., Smythers G. W., Oroszlan S. Chemical and immunological characterizations of equine infectious anemia virus gag-encoded proteins. J Virol. 1987 Apr;61(4):1116–1124. doi: 10.1128/jvi.61.4.1116-1124.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Hoshikawa N., Kojima A., Yasuda A., Takayashiki E., Masuko S., Chiba J., Sata T., Kurata T. Role of the gag and pol genes of human immunodeficiency virus in the morphogenesis and maturation of retrovirus-like particles expressed by recombinant vaccinia virus: an ultrastructural study. J Gen Virol. 1991 Oct;72(Pt 10):2509–2517. doi: 10.1099/0022-1317-72-10-2509. [DOI] [PubMed] [Google Scholar]
  21. Jowett J. B., Hockley D. J., Nermut M. V., Jones I. M. Distinct signals in human immunodeficiency virus type 1 Pr55 necessary for RNA binding and particle formation. J Gen Virol. 1992 Dec;73(Pt 12):3079–3086. doi: 10.1099/0022-1317-73-12-3079. [DOI] [PubMed] [Google Scholar]
  22. Kay J., Dunn B. M. Viral proteinases: weakness in strength. Biochim Biophys Acta. 1990 Jan 30;1048(1):1–18. doi: 10.1016/0167-4781(90)90015-t. [DOI] [PubMed] [Google Scholar]
  23. Konvalinka J., Heuser A. M., Hruskova-Heidingsfeldova O., Vogt V. M., Sedlacek J., Strop P., Kräusslich H. G. Proteolytic processing of particle-associated retroviral polyproteins by homologous and heterologous viral proteinases. Eur J Biochem. 1995 Feb 15;228(1):191–198. doi: 10.1111/j.1432-1033.1995.tb20249.x. [DOI] [PubMed] [Google Scholar]
  24. Kräusslich H. G., Ingraham R. H., Skoog M. T., Wimmer E., Pallai P. V., Carter C. A. Activity of purified biosynthetic proteinase of human immunodeficiency virus on natural substrates and synthetic peptides. Proc Natl Acad Sci U S A. 1989 Feb;86(3):807–811. doi: 10.1073/pnas.86.3.807. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Kräusslich H. G., Nicklin M. J., Toyoda H., Etchison D., Wimmer E. Poliovirus proteinase 2A induces cleavage of eucaryotic initiation factor 4F polypeptide p220. J Virol. 1987 Sep;61(9):2711–2718. doi: 10.1128/jvi.61.9.2711-2718.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Kräusslich H. G., Schneider H., Zybarth G., Carter C. A., Wimmer E. Processing of in vitro-synthesized gag precursor proteins of human immunodeficiency virus (HIV) type 1 by HIV proteinase generated in Escherichia coli. J Virol. 1988 Nov;62(11):4393–4397. doi: 10.1128/jvi.62.11.4393-4397.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Kräusslich H. G., Wimmer E. Viral proteinases. Annu Rev Biochem. 1988;57:701–754. doi: 10.1146/annurev.bi.57.070188.003413. [DOI] [PubMed] [Google Scholar]
  28. Kunkel T. A. Rapid and efficient site-specific mutagenesis without phenotypic selection. Proc Natl Acad Sci U S A. 1985 Jan;82(2):488–492. doi: 10.1073/pnas.82.2.488. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Leis J., Baltimore D., Bishop J. M., Coffin J., Fleissner E., Goff S. P., Oroszlan S., Robinson H., Skalka A. M., Temin H. M. Standardized and simplified nomenclature for proteins common to all retroviruses. J Virol. 1988 May;62(5):1808–1809. doi: 10.1128/jvi.62.5.1808-1809.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Mammano F., Ohagen A., Höglund S., Göttlinger H. G. Role of the major homology region of human immunodeficiency virus type 1 in virion morphogenesis. J Virol. 1994 Aug;68(8):4927–4936. doi: 10.1128/jvi.68.8.4927-4936.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Mergener K., Fäcke M., Welker R., Brinkmann V., Gelderblom H. R., Kräusslich H. G. Analysis of HIV particle formation using transient expression of subviral constructs in mammalian cells. Virology. 1992 Jan;186(1):25–39. doi: 10.1016/0042-6822(92)90058-w. [DOI] [PubMed] [Google Scholar]
  32. Mervis R. J., Ahmad N., Lillehoj E. P., Raum M. G., Salazar F. H., Chan H. W., Venkatesan S. The gag gene products of human immunodeficiency virus type 1: alignment within the gag open reading frame, identification of posttranslational modifications, and evidence for alternative gag precursors. J Virol. 1988 Nov;62(11):3993–4002. doi: 10.1128/jvi.62.11.3993-4002.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Pettit S. C., Moody M. D., Wehbie R. S., Kaplan A. H., Nantermet P. V., Klein C. A., Swanstrom R. The p2 domain of human immunodeficiency virus type 1 Gag regulates sequential proteolytic processing and is required to produce fully infectious virions. J Virol. 1994 Dec;68(12):8017–8027. doi: 10.1128/jvi.68.12.8017-8027.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Pettit S. C., Simsic J., Loeb D. D., Everitt L., Hutchison C. A., 3rd, Swanstrom R. Analysis of retroviral protease cleavage sites reveals two types of cleavage sites and the structural requirements of the P1 amino acid. J Biol Chem. 1991 Aug 5;266(22):14539–14547. [PubMed] [Google Scholar]
  35. Poorman R. A., Tomasselli A. G., Heinrikson R. L., Kézdy F. J. A cumulative specificity model for proteases from human immunodeficiency virus types 1 and 2, inferred from statistical analysis of an extended substrate data base. J Biol Chem. 1991 Aug 5;266(22):14554–14561. [PubMed] [Google Scholar]
  36. Richards A. D., Phylip L. H., Farmerie W. G., Scarborough P. E., Alvarez A., Dunn B. M., Hirel P. H., Konvalinka J., Strop P., Pavlickova L. Sensitive, soluble chromogenic substrates for HIV-1 proteinase. J Biol Chem. 1990 May 15;265(14):7733–7736. [PubMed] [Google Scholar]
  37. Royer M., Cerutti M., Gay B., Hong S. S., Devauchelle G., Boulanger P. Functional domains of HIV-1 gag-polyprotein expressed in baculovirus-infected cells. Virology. 1991 Sep;184(1):417–422. doi: 10.1016/0042-6822(91)90861-5. [DOI] [PubMed] [Google Scholar]
  38. Royer M., Hong S. S., Gay B., Cerutti M., Boulanger P. Expression and extracellular release of human immunodeficiency virus type 1 Gag precursors by recombinant baculovirus-infected cells. J Virol. 1992 May;66(5):3230–3235. doi: 10.1128/jvi.66.5.3230-3235.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  39. Royer W. E., Jr, Love W. E., Fenderson F. F. Cooperative dimeric and tetrameric clam haemoglobins are novel assemblages of myoglobin folds. Nature. 1985 Jul 18;316(6025):277–280. doi: 10.1038/316277a0. [DOI] [PubMed] [Google Scholar]
  40. Salahuddin S. Z., Markham P. D., Wong-Staal F., Franchini G., Kalyanaraman V. S., Gallo R. C. Restricted expression of human T-cell leukemia--lymphoma virus (HTLV) in transformed human umbilical cord blood lymphocytes. Virology. 1983 Aug;129(1):51–64. doi: 10.1016/0042-6822(83)90395-1. [DOI] [PubMed] [Google Scholar]
  41. Schechter I., Berger A. On the size of the active site in proteases. I. Papain. Biochem Biophys Res Commun. 1967 Apr 20;27(2):157–162. doi: 10.1016/s0006-291x(67)80055-x. [DOI] [PubMed] [Google Scholar]
  42. Tobin G. J., Sowder R. C., 2nd, Fabris D., Hu M. Y., Battles J. K., Fenselau C., Henderson L. E., Gonda M. A. Amino acid sequence analysis of the proteolytic cleavage products of the bovine immunodeficiency virus Gag precursor polypeptide. J Virol. 1994 Nov;68(11):7620–7627. doi: 10.1128/jvi.68.11.7620-7627.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Tritch R. J., Cheng Y. E., Yin F. H., Erickson-Viitanen S. Mutagenesis of protease cleavage sites in the human immunodeficiency virus type 1 gag polyprotein. J Virol. 1991 Feb;65(2):922–930. doi: 10.1128/jvi.65.2.922-930.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Tözsér J., Bláha I., Copeland T. D., Wondrak E. M., Oroszlan S. Comparison of the HIV-1 and HIV-2 proteinases using oligopeptide substrates representing cleavage sites in Gag and Gag-Pol polyproteins. FEBS Lett. 1991 Apr 9;281(1-2):77–80. doi: 10.1016/0014-5793(91)80362-7. [DOI] [PubMed] [Google Scholar]
  45. Weldon R. A., Jr, Erdie C. R., Oliver M. G., Wills J. W. Incorporation of chimeric gag protein into retroviral particles. J Virol. 1990 Sep;64(9):4169–4179. doi: 10.1128/jvi.64.9.4169-4179.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Wills J. W., Craven R. C. Form, function, and use of retroviral gag proteins. AIDS. 1991 Jun;5(6):639–654. doi: 10.1097/00002030-199106000-00002. [DOI] [PubMed] [Google Scholar]
  47. von Poblotzki A., Wagner R., Niedrig M., Wanner G., Wolf H., Modrow S. Identification of a region in the Pr55gag-polyprotein essential for HIV-1 particle formation. Virology. 1993 Apr;193(2):981–985. doi: 10.1006/viro.1993.1210. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Virology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES