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Presenilin 2 familial Alzheimer's disease mutations result in partial loss of function and dramatic changes in Abeta 42/40 ratios
Walker ES, Martinez M, Brunkan AL, Goate A.. Journal of neurochemistry, 2005-01-01
Topic: Disease mechanisms in lab and animal studies
Gene knockout studies in mice suggest that presenilin 1 (PS1) is the major gamma-secretase and that it contributes disproportionately to amyloid beta (Abeta) peptide generation from beta-amyloid precursor protein (APP), whereas PS2 plays a more minor role. Based on this and other observations we hypothesized that familial Alzheimer's disease (FAD) mutations in PS2 would have a dramatic effect on function in order to have an observable effect on Abeta levels in the presence of normal PS1 alleles. Only four of the eight reported FAD mutations in PS2 have altered function in vitro suggesting that the other variants represent rare polymorphisms rather than disease-causing mutations. In support of our hypothesis, the four verified PS2 FAD mutations cause substantial changes in the Abeta 42/40 ratio, comparable with PS1 mutations that cause very-early-onset FAD. Most of the PS2 mutations also cause a significant decrease in Abeta 40, APP C-terminal fragment (CTF)gamma and Notch intracellular domain (NICD) production suggesting that they are partial loss of function mutations. PS2 M239V, its PS1 homolog M233V, and other FAD mutations within transmembrane (TM) 5 of PS1 differentially affect CTFgamma and NICD production suggesting that TM5 of PS are important for gamma-secretase cleavage of APP but not Notch.
Key findings
- Gene knockout studies in mice suggest that presenilin 1 (PS1) is the major gamma-secretase and that it contributes disproportionately to amyloid beta (Abeta) peptide generation from beta-amyloid precursor protein (APP), whereas PS2 plays a more minor role.
- Only four of the eight reported FAD mutations in PS2 have altered function in vitro suggesting that the other variants represent rare polymorphisms rather than disease-causing mutations.
- Most of the PS2 mutations also cause a significant decrease in Abeta 40, APP C-terminal fragment (CTF)gamma and Notch intracellular domain (NICD) production suggesting that they are partial loss of function mutations.
- PS2 M239V, its PS1 homolog M233V, and other FAD mutations within transmembrane (TM) 5 of PS1 differentially affect CTFgamma and NICD production suggesting that TM5 of PS are important for gamma-secretase cleavage of APP but not Notch.
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Study details
- Evidence strengthLow
How this study scored 36/100
Published in a peer-reviewed journal. Scored zero for study design, sample size, effect reported, studied in people and randomised / blinded because the record does not state it. We have no data on journal's citation record, times cited, citations per year, impact for its field and year, cited by studies here, still being cited, senior author's track record, institution's track record and multi-centre collaboration, so those were left out: it earned 21 of the 58 points we could judge it on, which is 36 out of 100.
| Component | Points | Why |
|---|---|---|
| Journal tier | 7 / 10 | Tier 3 — peer-reviewed journal (Journal of neurochemistry) |
| Journal's citation record | — / 4 | No journal record from OpenAlex — left out of this score |
| Study design | 0 / 12 | No study design recorded — scores zero, not guessed (not stated in the record — scored 0) |
| Strength of evidence | 1 / 5 | Rated “low” in our summary |
| Peer-review validation | 10 / 10 | Peer-reviewed. Published as an article in a named peer-reviewed journal. |
| How recent | 1 / 5 | 2005 — older than 20 years, still counted |
| Sample size | 0 / 4 | Participant count not stated — scores zero (not stated in the record — scored 0) |
| Effect reported | 0 / 3 | No effect size reported — scores zero (not stated in the record — scored 0) |
| Studied in people | 0 / 3 | Not stated whether this was studied in people — scores zero (not stated in the record — scored 0) |
| Randomised / blinded | 0 / 2 | No randomisation or blinding stated — scores zero (not stated in the record — scored 0) |
| Times cited | — / 7 | No citation count (not found in OpenAlex) — left out of this score |
| Citations per year | — / 5 | No citation count or no year — left out of this score |
| Impact for its field and year | — / 6 | No field-weighted citation impact (OpenAlex has none yet) — left out of this score |
| Cited by studies here | — / 6 | Not yet checked against this library's citation graph — left out of this score |
| Still being cited | — / 4 | No yearly citation counts — left out of this score |
| Senior author's track record | — / 4 | Senior author's record not available — left out of this score |
| Institution's track record | — / 3 | No institution listed in OpenAlex — left out of this score |
| Multi-centre collaboration | — / 3 | Institutions not listed — left out of this score |
| Indexed in PubMed | 2 / 2 | Indexed in PubMed (PMID 15663477) |
| Free to read | 0 / 2 | Behind a paywall — scores zero |
| Points | 21 / 58 | Scored on 11 of 20 parts. We have no data for the rest, so they are left out: 21 of the 58 points we could judge it on is 36 out of 100. |
| Total | 36 / 100 | — |
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Cite this study APA, Vancouver, BibTeX · download .bib or .ris
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APA 7th
Walker, E. S., Martinez, M., Brunkan, A. L., & Goate, A. (2005). Presenilin 2 familial Alzheimer's disease mutations result in partial loss of function and dramatic changes in Abeta 42/40 ratios. Journal of neurochemistry. https://doi.org/10.1111/j.1471-4159.2004.02858.x
Vancouver
Walker ES, Martinez M, Brunkan AL, Goate A. Presenilin 2 familial Alzheimer's disease mutations result in partial loss of function and dramatic changes in Abeta 42/40 ratios. Journal of neurochemistry. 2005. doi:10.1111/j.1471-4159.2004.02858.x. PMID: 15663477.
BibTeX
@article{walker2005-15663477,
author = {Walker, E. S. and Martinez, M. and Brunkan, A. L. and Goate, A.},
title = {{Presenilin 2 familial Alzheimer's disease mutations result in partial loss of function and dramatic changes in Abeta 42/40 ratios}},
journal = {Journal of neurochemistry},
year = {2005},
doi = {10.1111/j.1471-4159.2004.02858.x},
pmid = {15663477},
url = {https://doi.org/10.1111/j.1471-4159.2004.02858.x}
}
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