Abstract
The vascular and parenchymal amyloid deposits in Alzheimer disease (AD), normal aging and Down syndrome are mainly composed of a 4 kDa polypeptide (A4), which derives from a larger precursor protein (APP). There is evidence that APP is a transmembrane glycoprotein present in most tissues, but the characteristics of APP in intact cells are not yet known. In order to investigate this issue, we examined the immunoreactivity of fibroblasts of human and nonhuman cell lines with antisera raised to synthetic peptides corresponding to A4 and to two other domains of the APP. All three antisera recognized a 130 kDa polypeptide (APP-130) in immunoblots from all cell lines. In fibroblasts, an additional polypeptide of 228 kDa (APP-228) was recognized by the antiserum to A4. In immunoblots of two dimensional gels, APP-130 showed a pI of 6.2, while APP-228 failed to focus in the pH range of 4.7-7.0. Sequential extractions of cells with buffer and with Triton X-100 indicate that APP-130 is extractable with nonionic detergents at high ionic strength, whereas 228 kDa APP is a cystolic component. Immunofluorescence staining is consistent with an intracellular perinuclear and plasma membrane localization. It is concluded that APP-130 and APP-228 are two forms of the APP which result from extensive posttranslational modifications of a smaller original gene product. It is likely that APP undergoes similar posttranslational modifications in different cell types.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 94-98 |
| Number of pages | 5 |
| Journal | FEBS Letters |
| Volume | 241 |
| Issue number | 1-2 |
| DOIs | |
| State | Published - Dec 5 1988 |
| Externally published | Yes |
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Keywords
- (Cell culture)
- Alzheimer's disease
- Amyloid
- Amyloid precursor protein
ASJC Scopus subject areas
- Biophysics
- Structural Biology
- Biochemistry
- Molecular Biology
- Genetics
- Cell Biology
Cite this
The amyloid precursor protein of Alzheimer disease is expressed as a 130 kDa polypeptide in various cultured cell types. / Autilio-Gambetti, L.; Morandi, A.; Tabaton, M.; Schaetzle, B.; Kovacs, D.; Perry, G.; Greenberg, Barry; Gambetti, P.
In: FEBS Letters, Vol. 241, No. 1-2, 05.12.1988, p. 94-98.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - The amyloid precursor protein of Alzheimer disease is expressed as a 130 kDa polypeptide in various cultured cell types
AU - Autilio-Gambetti, L.
AU - Morandi, A.
AU - Tabaton, M.
AU - Schaetzle, B.
AU - Kovacs, D.
AU - Perry, G.
AU - Greenberg, Barry
AU - Gambetti, P.
PY - 1988/12/5
Y1 - 1988/12/5
N2 - The vascular and parenchymal amyloid deposits in Alzheimer disease (AD), normal aging and Down syndrome are mainly composed of a 4 kDa polypeptide (A4), which derives from a larger precursor protein (APP). There is evidence that APP is a transmembrane glycoprotein present in most tissues, but the characteristics of APP in intact cells are not yet known. In order to investigate this issue, we examined the immunoreactivity of fibroblasts of human and nonhuman cell lines with antisera raised to synthetic peptides corresponding to A4 and to two other domains of the APP. All three antisera recognized a 130 kDa polypeptide (APP-130) in immunoblots from all cell lines. In fibroblasts, an additional polypeptide of 228 kDa (APP-228) was recognized by the antiserum to A4. In immunoblots of two dimensional gels, APP-130 showed a pI of 6.2, while APP-228 failed to focus in the pH range of 4.7-7.0. Sequential extractions of cells with buffer and with Triton X-100 indicate that APP-130 is extractable with nonionic detergents at high ionic strength, whereas 228 kDa APP is a cystolic component. Immunofluorescence staining is consistent with an intracellular perinuclear and plasma membrane localization. It is concluded that APP-130 and APP-228 are two forms of the APP which result from extensive posttranslational modifications of a smaller original gene product. It is likely that APP undergoes similar posttranslational modifications in different cell types.
AB - The vascular and parenchymal amyloid deposits in Alzheimer disease (AD), normal aging and Down syndrome are mainly composed of a 4 kDa polypeptide (A4), which derives from a larger precursor protein (APP). There is evidence that APP is a transmembrane glycoprotein present in most tissues, but the characteristics of APP in intact cells are not yet known. In order to investigate this issue, we examined the immunoreactivity of fibroblasts of human and nonhuman cell lines with antisera raised to synthetic peptides corresponding to A4 and to two other domains of the APP. All three antisera recognized a 130 kDa polypeptide (APP-130) in immunoblots from all cell lines. In fibroblasts, an additional polypeptide of 228 kDa (APP-228) was recognized by the antiserum to A4. In immunoblots of two dimensional gels, APP-130 showed a pI of 6.2, while APP-228 failed to focus in the pH range of 4.7-7.0. Sequential extractions of cells with buffer and with Triton X-100 indicate that APP-130 is extractable with nonionic detergents at high ionic strength, whereas 228 kDa APP is a cystolic component. Immunofluorescence staining is consistent with an intracellular perinuclear and plasma membrane localization. It is concluded that APP-130 and APP-228 are two forms of the APP which result from extensive posttranslational modifications of a smaller original gene product. It is likely that APP undergoes similar posttranslational modifications in different cell types.
KW - (Cell culture)
KW - Alzheimer's disease
KW - Amyloid
KW - Amyloid precursor protein
UR - http://www.scopus.com/inward/record.url?scp=0024165056&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0024165056&partnerID=8YFLogxK
U2 - 10.1016/0014-5793(88)81038-X
DO - 10.1016/0014-5793(88)81038-X
M3 - Article
C2 - 2904381
AN - SCOPUS:0024165056
VL - 241
SP - 94
EP - 98
JO - FEBS Letters
JF - FEBS Letters
SN - 0014-5793
IS - 1-2
ER -