PSEN1 ΔE9 Mutants

Mutation Pathogenicity DNA Change Expected RNA | Protein Consequence Coding/Non-Coding Genomic Region Neuropathology Biological Effect Primary
Papers
PSEN1 c.856+3089_943+467del (ΔE9)
AD : Not Classified, SP : Not Classified Deletion Deletion | Deletion Both Exon 9, Introns 8 and 9

Unknown but, in one carrier, MRI showed slight brain atrophy and SPECT showed hypoperfusion of the parietal lobes, precuneus, and posterior cingulate cortex.

Unknown, but other Δ9 mutations result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Fukuda et al., 2023
PSEN1 S290_S319delinsC
(ΔE9, Δ9)		 AD : Pathogenic Deletion Deletion | Deletion-Insertion Both Intron 8, Exon 9, Intron 9

Variable: lesions observed include cotton-wool plaques, cored plaques, and tangles. Corticospinal tract degeneration, cortical atrophy, and congophilic amyloid angiopathy also variably observed.

5.9 kb deletion including entire exon 9 and extending into flanking intronic sequences; results in skipping of exon 9 and S290C substitution at the splice junction of exons 8 and 10. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Smith et al., 2001
PSEN1 S290_S319delinsC
(ΔE9Finn, Δ9Finn, Δ9)		 AD : Pathogenic Deletion Deletion | Deletion-Insertion Both Intron 8, Exon 9, Intron 9

Variable across two families: One family had unusual plaques described as “reminiscent of loosely packed cotton-wool balls” which were large (100-150 μM in diameter) and not congophilic, suggesting a lack of amyloid at the core, in addition to more typical AD plaques and tangles. The other family had more typical AD pathology.

4.6 kb deletion including entire exon 9 and extending into flanking intronic sequences; results in skipping of exon 9 and S290C substitution at the splice junction of exons 8 and 10. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Crook et al., 1998;
Prihar et al., 1999
PSEN1 S290_S319delinsC G>A
(ΔE9, Δ9, c.869-1G>A)		 AD : Pathogenic Substitution Splicing Alteration | Deletion-Insertion Both Intron 8, Exon 9

Cotton-wool plaques are common, in addition to classic neuritic, amyloid plaques. Tangles, neuronal loss, atrophy typical of AD.

Point mutation in splice acceptor site in intron 8 resulting in skipping of exon 9 and S290C change at the splice junction of exons 8 and 10. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Sato et al., 1998
PSEN1 S290_S319delinsC G>T
(ΔE9, Δ9)		 AD : Pathogenic Substitution Splicing Alteration | Deletion-Insertion Both Intron 8, Exon 9

Cotton-wool plaques throughout the neocortex. Less frequent cored plaques. Neurofibrillary tangles, some neuronal loss, gliosis, and cerebral amyloid angiopathy.

Point mutation in a splice acceptor site in intron 8 resulting in in-frame skipping of exon 9 and S290C change at the splice junction of exon 8 and 10. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Perez-Tur et al., 1995;
Hutton et al., 1996
PSEN1 S290_S319delinsC A>G
(ΔE9, Δ9, c.869-2A>G)		 AD : Pathogenic Substitution Splicing Alteration | Deletion-Insertion Both Intron 8, Exon 9

Unknown; in one patient, MRI showed supratentorial atrophy, particularly of parietal and occipital cortex. Also, reduced Aβ42 in CSF.

Point mutation in splice acceptor site in intron 8 resulting in skipping of exon 9 and S290C change at the splice junction of exons 8 and 10. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Rovelet-Lecrux et al., 2015
PSEN1 c.869-22_869-23ins18
(ΔE9, Δ9, deltaE9)		 AD : Not Classified Insertion Splicing Alteration | Deletion Both Intron 8, Exon 9

Cotton-wool plaques in addition to widespread neurofibrillary tangles and neuritic plaques more typical of AD. Marked cerebral amyloid angiopathy.

Insertion of 18 nucleotides in intron 8 upstream of exon 9, resulting in exon 9 skipping. Δ9 mutations generally result in increased Aβ42/Aβ40 ratio and decreased Aβ (37 + 38 + 40) / (42 + 43) and Aβ37/Aβ42 ratios. They also disrupt multiple cellular functions.

 Dumanchin et al., 2006

The PSEN1 ΔE9 mutations include three deletion mutations, one insertion mutation, and three splice-site mutations within intron 8. Despite their heterogeneity, they all result in the absence of exon 9 from transcripts and the production of presenilin protein lacking a region of about 30 amino acids. Many, but not all, of the ΔE9 kindreds have a clinical phenotype that involves spastic paraparesis, although heterogeneity exists even within a family. The ΔE9 mutations are also frequently associated with neuropathological features atypical for AD, notably large deposits of Aβ known as "cotton-wool plaques," which lack an amyloid core. These plaques were first described in the Finnish pedigree with exon 9 deletion and subsequently have been observed in the brains of patients with ΔE9 mutations, as well as some missense mutations.

Biological Effects

Multiple in vitro and in vivo assays have shown that PSEN1 ΔE9 impairs endoproteolytic processing of PSEN1 (Thinakaran et al., 1996, Lee et al., 1997) and alters the production of Aβ42 and Aβ40 peptides resulting in an increased Aβ42/Aβ40 ratio (Borchelt et al., 1996, Steiner et al., 1999, Dumanchin et al., 2006; Kumar-Singh et al., 2006, Bentahir et al., 2006, Woodruff et al., 2013, Cacquevel et al., 2012, Sun et al., 2017). Moreover, studies surveying the production of Aβ peptides of different lengths have indicated that these mutations result in increased levels of longer Aβ peptides, and decreased levels of shorter peptides (Chávez-Gutiérrez et al., 2012; Svedružić et al., 2012; Kakuda et al., 2021). Chávez-Gutiérrez and colleagues proposed this is the result of impairment of the fourth γ-secretase cleavage in the two Aβ production lines that sequentially digest Aβ49 and Aβ48 into shorter peptides (Chávez-Gutiérrez et al., 2012).

Consistent with these findings, more recent studies revealed PSEN1ΔE9 mutants decrease the Aβ (37 + 38 + 40) / (42 + 43) ratio and the Aβ37/Aβ42 ratio, both of which reflect γ-processivity, compared with cells expressing wildtype PSEN1 (Apr 2022 news; Petit et al., 2022; Liu et al., 2022). The two ratios were reported to outperform the Aβ42/Aβ40 ratio as indicators of AD pathogenicity, with the former correlating with AD age at onset. Moreover, a follow-up study reported in a preprint, combined the Aβ (37 + 38 + 40) / (42 + 43) ratio with the commonly used Aβ42/Aβ40 ratio (a measure of the relative production of aggregation-prone Aβ) to yield a composite measure which reflects γ-secretase function as a percentage of wildtype activity (Schulz et al., 2023). This composite score (36.87 for PSEN1ΔE9) was strongly associated, not only with age at onset, but with biomarker and cognitive trajectories.

Exon 9 deletion mutations may also affect PSEN1 transcription. In a bacterial artificial chromosome (BAC)-based expression model, PSEN1ΔE9-expressing cells exhibited reduced PSEN1 gene expression and partial loss of function relative to cells expressing wild-type PSEN1 (Ahmadi et al., 2014).

The absence of exon 9 may impair Notch processing as well. Although one study found no effect of the mutation on this substrate (Chávez-Gutiérrez et al., 2012), others have reported impaired Notch S3 cleavage and corresponding alterations in the differentiation and self-renewal of neural progenitor cells in the adult mouse brain (Bentahir et al., 2006; Veeraraghavalu et al., 2010; May 2010 news).

PSEN1ΔE9 mutations have also been implicated in the disruption of several intracellular functions. For example, by lowering PIP2 levels, PSEN1ΔE9 appears to block a cation channel that mediates capacitive calcium entry (Landman et al., 2006; Dec 2006 news). In addition, impairments in endocytosis, cholesterol homeostasis, autophagy, and APP intracellular localization have been reported (Woodruff et al., 2016; Oct 2016 news; Cho et al., 2019; Oh and Chung, 2017). In addition, alterations in tight and adherens junction protein expression, as well as in efflux properties, were found in iPSC-derived brain endothelial cells, a model of blood-brain barrier function (Oikari et al., 2020).

Interestingly, PSEN1 was reported to play a key role in ApoE secretion and cytoplasmic localization. In experiments with PSEN-deficient fibroblasts, PSEN1ΔE9 transfection was less able to rescue these functions compared with transfection of wildtype PSEN1 (Islam et al., 2022).

PSEN1ΔE9 had little effect on microglia, a cell type that normally expresses very low levels of PSEN1, although it appeared to weaken the cells’ inflammatory response (Konttinen et al., 2019, Sep 2019 news). In a non-human primate model, transcriptomic and proteomic analyses of blood suggested early inflammatory and immune alterations (Li et al., 2024).

Research Models

Multiple mouse models that express PSEN1 lacking exon 9 have been developed. One line, referred to as S-9 (Lee et al., 1997), was subsequently bred to an APP transgenic line to generate APPSwe/PSEN1dE9, which has a more severe phenotype than either of the parental lines. Another double-transgenic model was made by co-injecting vectors expressing PSEN1ΔE9 and APP with the Swedish mutation (APPswe/PSEN1dE9 (Borchelt mice)). Although cotton-wool plaques are sometimes prominent in the brains of AD patients with ΔE9 mutations, this pathology has not been observed in ΔE9 mouse models.

In addition, induced pluripotent stem cell lines derived from patients have been used to generate neurons (Woodruff et al., 2013), astrocytes (Oksanen et al., 2017), and brain endothelial cells (Oikari et al., 2020) which display several features of AD pathology.

Cynomolgus monkeys lacking PSEN1 exon 9 have also been generated (Li et al., 2024). Initial characterization of proteins in blood and cerebrospinal fluid were reported, as well as transcriptomic analysis of blood, in heterozygote and homozygote juveniles.

Last Updated: 08 Jul 2024

References

News Citations

  1. Ratio of Short to Long Aβ Peptides: Better Handle on Alzheimer's than Aβ42/40?
  2. Notch Your Average Joe—Grounds for PS1 Neurogenesis Inhibition?
  3. Beyond γ-Secretase: FAD Mutations Affect Calcium Channel via Lipid Messenger
  4. Cholesterol Trafficking Takes a Hit in Alzheimer’s Neurons
  5. Among AD Mutations, Only ApoE4 Seems to Hobble Microglia

Paper Citations

  1. Thinakaran G, Borchelt DR, Lee MK, Slunt HH, Spitzer L, Kim G, Ratovitsky T, Davenport F, Nordstedt C, Seeger M, Hardy J, Levey AI, Gandy SE, Jenkins NA, Copeland NG, Price DL, Sisodia SS. Endoproteolysis of presenilin 1 and accumulation of processed derivatives in vivo. Neuron. 1996 Jul;17(1):181-90. PubMed.
  2. Lee MK, Borchelt DR, Kim G, Thinakaran G, Slunt HH, Ratovitski T, Martin LJ, Kittur A, Gandy S, Levey AI, Jenkins N, Copeland N, Price DL, Sisodia SS. Hyperaccumulation of FAD-linked presenilin 1 variants in vivo. Nat Med. 1997 Jul;3(7):756-60. PubMed.
  3. Borchelt DR, Thinakaran G, Eckman CB, Lee MK, Davenport F, Ratovitsky T, Prada CM, Kim G, Seekins S, Yager D, Slunt HH, Wang R, Seeger M, Levey AI, Gandy SE, Copeland NG, Jenkins NA, Price DL, Younkin SG, Sisodia SS. Familial Alzheimer's disease-linked presenilin 1 variants elevate Abeta1-42/1-40 ratio in vitro and in vivo. Neuron. 1996 Nov;17(5):1005-13. PubMed.
  4. Steiner H, Romig H, Grim MG, Philipp U, Pesold B, Citron M, Baumeister R, Haass C. The biological and pathological function of the presenilin-1 Deltaexon 9 mutation is independent of its defect to undergo proteolytic processing. J Biol Chem. 1999 Mar 19;274(12):7615-8. PubMed.
  5. Dumanchin C, Tournier I, Martin C, Didic M, Belliard S, Carlander B, Rouhart F, Duyckaerts C, Pellissier JF, Latouche JB, Hannequin D, Frebourg T, Tosi M, Campion D. Biological effects of four PSEN1 gene mutations causing Alzheimer disease with spastic paraparesis and cotton wool plaques. Hum Mutat. 2006 Oct;27(10):1063. PubMed.
  6. Kumar-Singh S, Theuns J, Van Broeck B, Pirici D, Vennekens K, Corsmit E, Cruts M, Dermaut B, Wang R, Van Broeckhoven C. Mean age-of-onset of familial alzheimer disease caused by presenilin mutations correlates with both increased Abeta42 and decreased Abeta40. Hum Mutat. 2006 Jul;27(7):686-95. PubMed.
  7. Bentahir M, Nyabi O, Verhamme J, Tolia A, Horré K, Wiltfang J, Esselmann H, De Strooper B. Presenilin clinical mutations can affect gamma-secretase activity by different mechanisms. J Neurochem. 2006 Feb;96(3):732-42. PubMed.
  8. Woodruff G, Young JE, Martinez FJ, Buen F, Gore A, Kinaga J, Li Z, Yuan SH, Zhang K, Goldstein LS. The presenilin-1 ΔE9 mutation results in reduced γ-secretase activity, but not total loss of PS1 function, in isogenic human stem cells. Cell Rep. 2013 Nov 27;5(4):974-85. Epub 2013 Nov 14 PubMed.
  9. Cacquevel M, Aeschbach L, Houacine J, Fraering PC. Alzheimer's disease-linked mutations in presenilin-1 result in a drastic loss of activity in purified γ-secretase complexes. PLoS One. 2012;7(4):e35133. PubMed.
  10. Sun L, Zhou R, Yang G, Shi Y. Analysis of 138 pathogenic mutations in presenilin-1 on the in vitro production of Aβ42 and Aβ40 peptides by γ-secretase. Proc Natl Acad Sci U S A. 2017 Jan 24;114(4):E476-E485. Epub 2016 Dec 5 PubMed.
  11. Chávez-Gutiérrez L, Bammens L, Benilova I, Vandersteen A, Benurwar M, Borgers M, Lismont S, Zhou L, Van Cleynenbreugel S, Esselmann H, Wiltfang J, Serneels L, Karran E, Gijsen H, Schymkowitz J, Rousseau F, Broersen K, De Strooper B. The mechanism of γ-Secretase dysfunction in familial Alzheimer disease. EMBO J. 2012 May 16;31(10):2261-74. Epub 2012 Apr 13 PubMed.
  12. Svedružić ZM, Popović K, Smoljan I, Sendula-Jengić V. Modulation of γ-secretase activity by multiple enzyme-substrate interactions: implications in pathogenesis of Alzheimer's disease. PLoS One. 2012;7(3):e32293. PubMed.
  13. Kakuda N, Takami M, Okochi M, Kasuga K, Ihara Y, Ikeuchi T. Switched Aβ43 generation in familial Alzheimer's disease with presenilin 1 mutation. Transl Psychiatry. 2021 Nov 3;11(1):558. PubMed.
  14. Petit D, Fernández SG, Zoltowska KM, Enzlein T, Ryan NS, O'Connor A, Szaruga M, Hill E, Vandenberghe R, Fox NC, Chávez-Gutiérrez L. Aβ profiles generated by Alzheimer's disease causing PSEN1 variants determine the pathogenicity of the mutation and predict age at disease onset. Mol Psychiatry. 2022 Jun;27(6):2821-2832. Epub 2022 Apr 1 PubMed.
  15. Liu L, Lauro BM, He A, Lee H, Bhattarai S, Wolfe MS, Bennett DA, Karch CM, Young-Pearse T, Dominantly Inherited Alzheimer Network (DIAN), Selkoe DJ. Identification of the Aβ37/42 peptide ratio in CSF as an improved Aβ biomarker for Alzheimer's disease. Alzheimers Dement. 2022 Mar 12; PubMed.
  16. Schultz S, Liu L, Schultz A, Fitzpatrick C, Levin R, Bellier J-P, Shirzadi Z, Mathurin N, Chen C, Benzinger T, Day G, Farlow M, Gordon B, Hassenstab J, Jack C, Jucker M, Karch C, Lee J, Levin J, Perrin R, Schofield P, Xiong C, Johnson K, McDade E, Bateman R, Sperling R, Selkoe D, Chhatwal J, theDominantlyInheritedAlzheimer'sNetworkInvestigators. Functional variations in gamma-secretase activity are critical determinants of the clinical, biomarker, and cognitive progression of autosomal dominant Alzheimer's disease. 2023 Jul 25 10.1101/2023.07.04.547688 (version 2) bioRxiv.
  17. Ahmadi S, Wade-Martins R. Familial Alzheimer's disease coding mutations reduce Presenilin-1 expression in a novel genomic locus reporter model. Neurobiol Aging. 2014 Feb;35(2):443.e5-443.e16. PubMed.
  18. Veeraraghavalu K, Choi SH, Zhang X, Sisodia SS. Presenilin 1 mutants impair the self-renewal and differentiation of adult murine subventricular zone-neuronal progenitors via cell-autonomous mechanisms involving notch signaling. J Neurosci. 2010 May 19;30(20):6903-15. PubMed.
  19. Landman N, Jeong SY, Shin SY, Voronov SV, Serban G, Kang MS, Park MK, Di Paolo G, Chung S, Kim TW. Presenilin mutations linked to familial Alzheimer's disease cause an imbalance in phosphatidylinositol 4,5-bisphosphate metabolism. Proc Natl Acad Sci U S A. 2006 Dec 19;103(51):19524-9. PubMed.
  20. Woodruff G, Reyna SM, Dunlap M, Van Der Kant R, Callender JA, Young JE, Roberts EA, Goldstein LS. Defective Transcytosis of APP and Lipoproteins in Human iPSC-Derived Neurons with Familial Alzheimer's Disease Mutations. Cell Rep. 2016 Oct 11;17(3):759-773. PubMed.
  21. Cho YY, Kwon OH, Park MK, Kim TW, Chung S. Elevated cellular cholesterol in Familial Alzheimer's presenilin 1 mutation is associated with lipid raft localization of β-amyloid precursor protein. PLoS One. 2019;14(1):e0210535. Epub 2019 Jan 25 PubMed.
  22. Oh HG, Chung S. Activation of transient receptor potential melastatin 7 (TRPM7) channel increases basal autophagy and reduces amyloid β-peptide. Biochem Biophys Res Commun. 2017 Nov 4;493(1):494-499. Epub 2017 Sep 1 PubMed.
  23. Oikari LE, Pandit R, Stewart R, Cuní-López C, Quek H, Sutharsan R, Rantanen LM, Oksanen M, Lehtonen S, de Boer CM, Polo JM, Götz J, Koistinaho J, White AR. Altered Brain Endothelial Cell Phenotype from a Familial Alzheimer Mutation and Its Potential Implications for Amyloid Clearance and Drug Delivery. Stem Cell Reports. 2020 May 12;14(5):924-939. Epub 2020 Apr 9 PubMed.
  24. Islam S, Sun Y, Gao Y, Nakamura T, Noorani AA, Li T, Wong PC, Kimura N, Matsubara E, Kasuga K, Ikeuchi T, Tomita T, Zou K, Michikawa M. Presenilin Is Essential for ApoE Secretion, a Novel Role of Presenilin Involved in Alzheimer's Disease Pathogenesis. J Neurosci. 2022 Feb 23;42(8):1574-1586. Epub 2022 Jan 5 PubMed.
  25. Konttinen H, Cabral-da-Silva ME, Ohtonen S, Wojciechowski S, Shakirzyanova A, Caligola S, Giugno R, Ishchenko Y, Hernández D, Fazaludeen MF, Eamen S, Budia MG, Fagerlund I, Scoyni F, Korhonen P, Huber N, Haapasalo A, Hewitt AW, Vickers J, Smith GC, Oksanen M, Graff C, Kanninen KM, Lehtonen S, Propson N, Schwartz MP, Pébay A, Koistinaho J, Ooi L, Malm T. PSEN1ΔE9, APPswe, and APOE4 Confer Disparate Phenotypes in Human iPSC-Derived Microglia. Stem Cell Reports. 2019 Oct 8;13(4):669-683. Epub 2019 Sep 12 PubMed.
  26. Li M, Guan M, Lin J, Zhu K, Zhu J, Guo M, Li Y, Chen Y, Chen Y, Zou Y, Wu D, Xu J, Yi W, Fan Y, Ma S, Chen Y, Xu J, Yang L, Dai J, Ye T, Lu Z, Chen Y. Early blood immune molecular alterations in cynomolgus monkeys with a PSEN1 mutation causing familial Alzheimer's disease. Alzheimers Dement. 2024 Jul 7; PubMed.
  27. Oksanen M, Petersen AJ, Naumenko N, Puttonen K, Lehtonen Š, Gubert Olivé M, Shakirzyanova A, Leskelä S, Sarajärvi T, Viitanen M, Rinne JO, Hiltunen M, Haapasalo A, Giniatullin R, Tavi P, Zhang SC, Kanninen KM, Hämäläinen RH, Koistinaho J. PSEN1 Mutant iPSC-Derived Model Reveals Severe Astrocyte Pathology in Alzheimer's Disease. Stem Cell Reports. 2017 Dec 12;9(6):1885-1897. Epub 2017 Nov 16 PubMed.

Other Citations

  1. APPSwe/PSEN1dE9

Disclaimer: Alzforum does not provide medical advice. The Content is for informational, educational, research and reference purposes only and is not intended to substitute for professional medical advice, diagnosis or treatment. Always seek advice from a qualified physician or health care professional about any medical concern, and do not disregard professional medical advice because of anything you may read on Alzforum.