Abstract
The β-amyloid precursor protein (APP) is connected to Alzheimer’s disease by both biochemistry and genetics. As the source of the major constituent of amyloid plaques, APP has been the subject of many studies of its expression and metabolism. The accumulation of amyloid β-peptide (Aβ) in these plaques was the first evidence that APP might be processed abnormally in Alzheimer’s, and this idea was strengthened by the discovery of mutations in APP that segregate with the disease with high penetrance. Aberrant processing of APP was incorporated into the Amyloid Hypothesis, which supposes that the clinical symptoms, neuropathology, and ultimate fatality of Alzheimer’s result from the actions of Aβ. But to the extent that the Amyloid Hypothesis remains hypothetical, it would be irresponsible to ignore other theories that might explain the links between APP and Alzheimer’s. APP can be proteolytically processed in a way that does not produce (and, in fact, precludes) Aβ. This “α-secretase” event cleaves within the Aβ sequence and liberates most of the extracellular portion (sAPPα) of APP from the cell surface Fig. 1). Because the “β-secretase” event required for the generation of Aβ creates a different soluble derivative (sAPPβ), disease-related increases in β-secretase processing —such as demonstrated with the “Swedish” mutation of APP—have the potential to affect events dependent on the normal function(s) of sAPPα. Furthermore, the increases in APP expression that occur as a result of injury or trisomy 21 may elevate the total levels of all sAPP species. To understand the implications of these events, it is critical to elucidate the biological activities of sAPPα and related moieties.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
References
Knauer, D. J., Thompson, J. A., and Cunningham, D. D. (1983) Protease nexins: cell-secreted proteins that mediate the binding, internalization, and degradation of regulatory serine proteases. J. Cell. Physiol. 117, 385–396.
Oltersdorf, T., Fritz, L. C., Schenk, D. B., Lieberburg, I., Johnson-Wood, K. L., Beattie, E. C., et al. (1989) The secreted form of the Alzheimer’s amyloid precursor protein with the Kunitz domain is protease nexin-II. Nature 341, 144–147.
Van Nostrand, W. E., Wagner, S. L., Suzuki, M., Choi, B. H., Farrow, J. S., Geddes, J. W., et al. (1989) Protease nexin-II, a potent antichymotrypsin, shows identity to amyloid β-protein precursor. Nature 341, 546–549.
Miyazaki, K., Hasegawa, M., Funahashi, K., and Umeda, M. (1993) A metalloproteinase inhibitor domain in Alzheimer amyloid protein precursor. Nature 362, 839–841.
Saitoh, T., Sundsmo, M., Roch, J.-M., Ximura, M., Cole, G., Schubert, D., et al. (1989) Secreted form of amyloid β protein precursor is involved in the growth regulation of fibroblasts. Cell 58, 615–622.
Mattson, M. P., Cheng, B., Culwell, A. R., Esch, F. S., Lieberburg, I., and Rydel, R. E. (1993) Evidence for excitoprotective and intraneuronal calcium-regulating roles for secreted forms of the β-amyloid precursor protein. Neuron 10, 243–254.
Furukawa, K., Barger, S. W., Blalock, E. M., and Mattson, M. P. (1996) Activation of potassium channels and suppression of neuronal activity by secreted β-amyloid precursor protein. Nature 379, 74–78.
Ishida, A., Furukawa, K., Keller, J. N., and Mattson, M. P. (1997) Secreted form of β-amyloid precursor protein shifts the frequency dependency for induction of LTD, and enhances LTP in hippocampal slices. Neuroreport 8, 2133–2137.
Barger, S. W., Fiscus, R. R., Ruth, P., Hofmann, F., and Mattson, M. P. (1995) The role of cyclic GMP in the regulation of neuronal calcium and survival by secreted forms of β-amyloid precursor. J. Neurochem. 64, 2087–2096.
Furukawa, K., Sopher, B. L., Rydel, R. E., Begley, J. G., Pham, D. G., Martin, G. M., et al. (1996) Increased activity-regulating andneuroprotective efficacy of α-secretase-derived secreted amyloid precursor protein conferred by a c-terminal heparin-binding domain. J. Neurochem. 67, 1882–1896.
Small, D. H., Nurcombe, V., Reed, G., Clarris, H., Moir, R., Beyreuther, K., and Masters C. L. (1994) A heparin-binding domain in the amyloid protein precursor of Alzheimer’s disease is involved in the regulation of neurite outgrowth. J. Neurosci. 14, 2117–2127.
Jin, L. W., Ninomiya, H., Roch, J. M., Schubert, D., Masliah, E., Otero, D. A., and Saitoh, T. (1994) Peptides containing the RERMS sequence of amyloid β/A4 protein precursor bind cell surface and promote neurite extension. J. Neurosci. 14, 5461–5470.
Barger, S. W. and Harmon, A. D. (1997) Microglial activation by secreted Alzheimer amyloid precursor protein and modulation by apolipoprotein E. Nature 388, 878–881.
Li, H. L., Roch, J. M., Sundsmo, M., Otero, D., Sisodia, S., Thomas, R., and Saitoh, T. (1997) Defective neurite extension is caused by a mutation in amyloid β/A4 (Aβ) protein precursor found in familial Alzheimer’s disease. Neurobiology 32, 469–480.
Barger, S. W. and Mattson, M. P. (1997) Isoform-specific modulation by apolipoprotein E of the activities of secreted β-amyloid precursor protein. J. Neurochem. 69, 60–67.
Sambrook, J., Fritsch E. F., and Maniatis, T. (eds.) (1989) Molecular Cloning, A Laboratory Manual, 2nd ed. Cold Spring Harbor Laboratory Press, Plainview NY, pp. E37–E38.
Kaufman, R. J. (1997) Expression of proteins in mammalian cells, in Current Protocols in Molecular Biology (Ausubel, F. M. et al., eds.), Wiley, New York, pp. 16.12.1–16.14.13.
Xpress System Protein Purification, Version B; Invitrogen, San Diego CA.
Barger, S. W. and Mattson, M. P. (1995) Secreted form of the Alzheimer’s β-amyloid precursor protein stimulates a membrane-associated guanylate cyclase. Biochem. J. 311, 45–47.
Mattson, M. P., Barger, S. W., Begley, J., and Mark, R. J. (1995) Calcium, free radicals, and excitotoxic neuronal death in primary cell culture. Methods Cell. Biol. 46, 187–216.
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2000 Humana Press Inc., Totowa, NJ
About this protocol
Cite this protocol
Barger, S.W. (2000). Production and Functional Assays of Recombinant Secreted Amyloid Precursor Protein (APP) (sAPPα). In: Hooper, N.M. (eds) Alzheimer's Disease. Methods in Molecular Medicine™, vol 32. Humana Press. https://doi.org/10.1385/1-59259-195-7:63
Download citation
DOI: https://doi.org/10.1385/1-59259-195-7:63
Publisher Name: Humana Press
Print ISBN: 978-0-89603-737-3
Online ISBN: 978-1-59259-195-4
eBook Packages: Springer Protocols