Abstract
The extracellular domain of the subgroup A avian sarcoma and leukemia virus (ALSV-A) receptor contains a region that is related in sequence to the ligand-binding motifs of the low-density lipoprotein receptor (LDLR). This domain contains six cysteines that are highly conserved between different members of the LDLR protein superfamily, and these residues are presumed to participate in intrachain disulfide bonds. To assess the importance of each cysteine in the ALSV-A receptor, individual or multiple cysteines were mutated to alanines and the altered receptors were tested for the ability to confer susceptibility to viral infection. Receptors bearing single mutations allowed subgroup A viral entry, albeit at less than wild-type levels. Receptors containing two or three substitutions were completely inactive if one of the changed residues was Cys-35 or Cys-50. Of the altered receptors tested, the only exception to this rule was a functional receptor which lacked both Cys-35 and Cys-50, an activity that was dependent on the presence of other cysteines in this protein. Most interestingly, a receptor containing both Cys-35 and Cys-50 but lacking the other four cysteines was completely functional. These results demonstrate the importance of Cys-35 and Cys-50 for viral entry mediated by the ALSV-A receptor and show that in the presence of these two residues, all of the other cysteines in this protein can be removed without loss of this function.
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- Bardwell J. C., Beckwith J. The bonds that tie: catalyzed disulfide bond formation. Cell. 1993 Sep 10;74(5):769–771. doi: 10.1016/0092-8674(93)90455-y. [DOI] [PubMed] [Google Scholar]
- Bates P., Young J. A., Varmus H. E. A receptor for subgroup A Rous sarcoma virus is related to the low density lipoprotein receptor. Cell. 1993 Sep 24;74(6):1043–1051. doi: 10.1016/0092-8674(93)90726-7. [DOI] [PubMed] [Google Scholar]
- Catterall C. F., Lyons A., Sim R. B., Day A. J., Harris T. J. Characterization of primary amino acid sequence of human complement control protein factor I from an analysis of cDNA clones. Biochem J. 1987 Mar 15;242(3):849–856. doi: 10.1042/bj2420849. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Connolly L., Zingler K., Young J. A. A soluble form of a receptor for subgroup A avian leukosis and sarcoma viruses (ALSV-A) blocks infection and binds directly to ALSV-A. J Virol. 1994 Apr;68(4):2760–2764. doi: 10.1128/jvi.68.4.2760-2764.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cunningham B. C., Wells J. A. High-resolution epitope mapping of hGH-receptor interactions by alanine-scanning mutagenesis. Science. 1989 Jun 2;244(4908):1081–1085. doi: 10.1126/science.2471267. [DOI] [PubMed] [Google Scholar]
- Daniel T. O., Schneider W. J., Goldstein J. L., Brown M. S. Visualization of lipoprotein receptors by ligand blotting. J Biol Chem. 1983 Apr 10;258(7):4606–4611. [PubMed] [Google Scholar]
- Esser V., Limbird L. E., Brown M. S., Goldstein J. L., Russell D. W. Mutational analysis of the ligand binding domain of the low density lipoprotein receptor. J Biol Chem. 1988 Sep 15;263(26):13282–13290. [PubMed] [Google Scholar]
- Esser V., Russell D. W. Transport-deficient mutations in the low density lipoprotein receptor. Alterations in the cysteine-rich and cysteine-poor regions of the protein block intracellular transport. J Biol Chem. 1988 Sep 15;263(26):13276–13281. [PubMed] [Google Scholar]
- Field J., Nikawa J., Broek D., MacDonald B., Rodgers L., Wilson I. A., Lerner R. A., Wigler M. Purification of a RAS-responsive adenylyl cyclase complex from Saccharomyces cerevisiae by use of an epitope addition method. Mol Cell Biol. 1988 May;8(5):2159–2165. doi: 10.1128/mcb.8.5.2159. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Gluzman Y. SV40-transformed simian cells support the replication of early SV40 mutants. Cell. 1981 Jan;23(1):175–182. doi: 10.1016/0092-8674(81)90282-8. [DOI] [PubMed] [Google Scholar]
- Goldstein J. L., Brown M. S., Anderson R. G., Russell D. W., Schneider W. J. Receptor-mediated endocytosis: concepts emerging from the LDL receptor system. Annu Rev Cell Biol. 1985;1:1–39. doi: 10.1146/annurev.cb.01.110185.000245. [DOI] [PubMed] [Google Scholar]
- Lehrman M. A., Schneider W. J., Brown M. S., Davis C. G., Elhammer A., Russell D. W., Goldstein J. L. The Lebanese allele at the low density lipoprotein receptor locus. Nonsense mutation produces truncated receptor that is retained in endoplasmic reticulum. J Biol Chem. 1987 Jan 5;262(1):401–410. [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Tyers M., Tokiwa G., Nash R., Futcher B. The Cln3-Cdc28 kinase complex of S. cerevisiae is regulated by proteolysis and phosphorylation. EMBO J. 1992 May;11(5):1773–1784. doi: 10.1002/j.1460-2075.1992.tb05229.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Weissman J. S., Kim P. S. Efficient catalysis of disulphide bond rearrangements by protein disulphide isomerase. Nature. 1993 Sep 9;365(6442):185–188. doi: 10.1038/365185a0. [DOI] [PubMed] [Google Scholar]
- Wigler M., Silverstein S., Lee L. S., Pellicer A., Cheng Y. c., Axel R. Transfer of purified herpes virus thymidine kinase gene to cultured mouse cells. Cell. 1977 May;11(1):223–232. doi: 10.1016/0092-8674(77)90333-6. [DOI] [PubMed] [Google Scholar]
- Wilson R., Ainscough R., Anderson K., Baynes C., Berks M., Bonfield J., Burton J., Connell M., Copsey T., Cooper J. 2.2 Mb of contiguous nucleotide sequence from chromosome III of C. elegans. Nature. 1994 Mar 3;368(6466):32–38. doi: 10.1038/368032a0. [DOI] [PubMed] [Google Scholar]
- Young J. A., Bates P., Varmus H. E. Isolation of a chicken gene that confers susceptibility to infection by subgroup A avian leukosis and sarcoma viruses. J Virol. 1993 Apr;67(4):1811–1816. doi: 10.1128/jvi.67.4.1811-1816.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
