Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1980 May;77(5):2984–2988. doi: 10.1073/pnas.77.5.2984

Electrophoretic properties of the scrapie agent in agarose gels.

S B Prusiner, D F Groth, C Bildstein, F R Masiarz, M P McKinley, S P Cochran
PMCID: PMC349531  PMID: 6771764

Abstract

The molecular properties of the scrapie agent were investigated by subjecting partially purified preparations to electrophoresis on agarose gels. When electrophoresis was performed at room temperature in the presence of sodium dodecyl sulfate (NaDodSO4), most of the recoverable agent was found at the top of the gel, consistent with previous studies indicating aggregation of the agent upon exposure to elevated temperatures. In addition, less than 5% of the agent applied to the gel was found after electrophoresis, even though the study was performed with a low concentration of NaDodSO4 (0.1%). Further studies on the inactivation of the agent by NaDodSO4 suggest that this may be, in part, a function of the NaDodSO4: protein ratio in the sample. In contrast, sodium N-lauroyl sarcosinate (Sarkosyl) did not inactivate the agent in concentrations as high as 5% (wt/vol). Virtually all of the infectivity could be recovered after electrophoresis of the agent into 0.6% agarose gels at 4 degrees C in the presence of 0.2% Sarkosyl. Digestion of the preparations with micrococcal nuclease and proteinase K prior to Sarkosyl electrophoresis caused a substantial portion of the agent to migrate ahead of DNA fragments of 1 x 10(6) daltons. The behavior of the scrapie agent in electrophoretic gels is consistent with earlier studies showing that the monomeric form of the agent has a sedimentation coefficient of less than or equal to 40 S. Thus, the smallest or monomeric form of the agent is smaller than any known animal virus.

Full text

PDF
2984

Images in this article

Selected References

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

  1. Dickinson A. G., Meikle V. M., Fraser H. Genetical control of the concentration of ME7 scrapie agent in the brain of mice. J Comp Pathol. 1969 Jan;79(1):15–22. doi: 10.1016/0021-9975(69)90021-8. [DOI] [PubMed] [Google Scholar]
  2. Gajdusek D. C. Unconventional viruses and the origin and disappearance of kuru. Science. 1977 Sep 2;197(4307):943–960. doi: 10.1126/science.142303. [DOI] [PubMed] [Google Scholar]
  3. Helenius A., Simons K. Charge shift electrophoresis: simple method for distinguishing between amphiphilic and hydrophilic proteins in detergent solution. Proc Natl Acad Sci U S A. 1977 Feb;74(2):529–532. doi: 10.1073/pnas.74.2.529. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Hunter G. D., Gibbons R. A., Kimberlin R. H., Millson G. C. Further studies of the infectivity and stability of extracts and homogenates derived from scrapie affected mouse brains. J Comp Pathol. 1969 Jan;79(1):101–108. doi: 10.1016/0021-9975(69)90033-4. [DOI] [PubMed] [Google Scholar]
  5. Hunter G. D., Gibbons R. A., Kimberlin R. H., Millson G. C. Further studies of the infectivity and stability of extracts and homogenates derived from scrapie affected mouse brains. J Comp Pathol. 1969 Jan;79(1):101–108. doi: 10.1016/0021-9975(69)90033-4. [DOI] [PubMed] [Google Scholar]
  6. Hunter G. D., Millson G. C. Attempts to release the scrapie agent from tissue debris. J Comp Pathol. 1967 Jul;77(3):301–307. doi: 10.1016/0021-9975(67)90039-4. [DOI] [PubMed] [Google Scholar]
  7. Kimberlin R. H., Walker C. Characteristics of a short incubation model of scrapie in the golden hamster. J Gen Virol. 1977 Feb;34(2):295–304. doi: 10.1099/0022-1317-34-2-295. [DOI] [PubMed] [Google Scholar]
  8. Liao T. Reversible inactivation of pancreatic deoxyribonuclease A by sodium dodecyl sulfate. Removal of COOH-terminal residues from the denatured protein by carboxypeptidase A. J Biol Chem. 1975 May 25;250(10):3831–3836. [PubMed] [Google Scholar]
  9. Malone T. G., Marsh R. F., Hanson R. P., Semancik J. S. Evidence for the low molecular weight nature of scrapie agent. Nature. 1979 Apr 5;278(5704):575–576. doi: 10.1038/278575a0. [DOI] [PubMed] [Google Scholar]
  10. Marsh R. F., Malone T. G., Semancik J. S., Lancaster W. D., Hanson R. P. Evidence for an essential DNA component in the Scrapie agent. Nature. 1978 Sep 14;275(5676):146–147. doi: 10.1038/275146a0. [DOI] [PubMed] [Google Scholar]
  11. Prusiner S. B., Hadlow W. J., Eklund C. M., Race R. E., Cochran S. P. Sedimentation characteristics of the scrapie agent from murine spleen and brain. Biochemistry. 1978 Nov 14;17(23):4987–4992. doi: 10.1021/bi00616a020. [DOI] [PubMed] [Google Scholar]
  12. Prusiner S. B., Hadlow W. J., Garfin D. E., Cochran S. P., Baringer J. R., Race R. E., Eklund C. M. Partial purification and evidence for multiple molecular forms of the scrapie agent. Biochemistry. 1978 Nov 14;17(23):4993–4999. doi: 10.1021/bi00616a021. [DOI] [PubMed] [Google Scholar]
  13. Reynolds J. A., Tanford C. Binding of dodecyl sulfate to proteins at high binding ratios. Possible implications for the state of proteins in biological membranes. Proc Natl Acad Sci U S A. 1970 Jul;66(3):1002–1007. doi: 10.1073/pnas.66.3.1002. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Robinson N. C., Tanford C. The binding of deoxycholate, Triton X-100, sodium dodecyl sulfate, and phosphatidylcholine vesicles to cytochrome b5. Biochemistry. 1975 Jan 28;14(2):369–378. doi: 10.1021/bi00673a025. [DOI] [PubMed] [Google Scholar]
  15. Tanford C., Reynolds J. A. Characterization of membrane proteins in detergent solutions. Biochim Biophys Acta. 1976 Oct 26;457(2):133–170. doi: 10.1016/0304-4157(76)90009-5. [DOI] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES