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Polymorphisms in the Promoter of the Human APP Gene
Functional Evaluation and Allele Frequencies in Alzheimer Disease
Eleni S. Athan, PhD;
Joseph H. Lee, PhD;
Alex Arriaga, BA;
Richard P. Mayeux, MD,MPH;
Benjamin Tycko, MD,PhD
Arch Neurol. 2002;59:1793-1799.
ABSTRACT
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Background Missense mutations in the amyloid precursor protein (APP) gene cause early-onset Alzheimer disease (AD). However, little is known regarding the effects of polymorphisms in regulatory sequences of APP on AD susceptibility.
Objectives To identify polymorphisms in the APP promoter, to test these for associations with AD, and to assess their influence on APP promoter activity in transfected cells.
Setting Community study of 1013 people of white, African American, or Caribbean Hispanic ethnicity, 65 years and older, residing in northern Manhattan.
Main Outcome Measures The diagnosis of AD was established by stringent criteria, with multiple follow-up examinations over 7 years.
Results We identified 2 polymorphisms in the APP promoter: a rare G C variant at –9 and a frequent GC variant at +37 relative to the transcription start site. The +37C allele was most frequent in African American patients (18% frequency), followed by Caribbean Hispanic patients (10%) and white patients of European descent (3%). This allele was overrepresented among patients with AD compared with elderly controls (odds ratio [OR], 1.57; 95% confidence interval [CI], 1.08-2.27 in the combined ethnic groups), but this was not significant after adjusting for age, sex, and education (OR, 1.41; 95% CI, 0.93-2.12). A stronger association was found in participants lacking any apolipoprotein-E  4 allele (OR, 2.12; 95% CI, 1.36-3.32 [univariate analysis]; OR, 2.08; 95% CI, 1.26-3.45 after adjusting for age, sex, and education). The –9C allele was not frequent enough to be evaluated for a disease association. Both variants were tested in promoter-reporter assays in U-87 glioma cells, and no differences in promoter activity were detected.
Conclusions The –9G/C and +37G/C APP promoter polymorphisms are unlikely to contribute strongly to AD susceptibility or to cause major differences in APP expression, but the +37C allele warrants further study for association with AD in larger population samples.
INTRODUCTION
THE NEUROTOXIC and amyloidogenic peptide A is generated by proteolytic cleavage of the amyloid precursor protein (APP).1 Genetic and functional studies have assigned a pivotal role for increased A production in the neuropathologic characteristics of Alzheimer disease (AD). Several factors account for the increased secretion of A and the accelerated aggregation of this peptide in AD. These include missense mutations in the APP gene and in the genes encoding presenilin-1 and presenilin-2, which increase the proteolytic conversion of APP into the fibrillogenic A42 peptide and lead to early-onset AD.2-4 A coding change in a third locus, the apolipoprotein-E (APOE) 4 variant, acts to increase A aggregation and is a significant risk factor for late-onset AD.5-6
Since the production of A is predicted to depend both on the amount of APP protein and on factors involved in its processing, a link between increased APP gene expression and AD has been examined. Increased expression of the APP gene correlates with A accumulation in severe head injury in humans, and overexpression, but not low-level expression, of APP missense alleles in transgenic mice mimics some aspects of AD.7-9 Perhaps most convincingly, APP gene duplication in trisomy 21 leads to elevated levels of circulating A peptide10 and to premature accumulation of A in amyloid plaques in the brain,11-12 a process that likely contributes to the observed approximately 40-year decrease in age of onset of AD in people with Down syndrome.13-14
Although the molecular mechanisms governing APP gene expression are not fully understood, the APP promoter is an essential regulatory element that is highly conserved between species. It resembles promoters of housekeeping genes in that the proximal region has a high GC content and lacks typical CAAT and TATA boxes. The APP promoter contains consensus binding sites for several transcription factors that respond to signals from extracellular ligands and cell stress and an initiator sequence that is essential for start site selection.15-26 Little information is available concerning genetic variation in APP regulatory sequences. To date, the screening for variants in the APP promoter identified a CG substitution at position -209 relative to the transcription start site, which was stated as not associating with AD, although data on allele frequencies were not shown.27-28 Another polymorphic marker, a microsatellite sequence in the first intron of APP, showed weak association with AD in a recent sibling study,29 but a tetranucleotide repeat in intron 7 did not associate with AD.30 To address this issue more fully, we have screened for APP promoter variants in a large tri-ethnic population sample of elderly Caribbean Hispanic, African American, and white participants. We report functional and genetic association data for 2 APP promoter polymorphisms found in this population.
METHODS
PARTICIPANTS AND DIAGNOSIS
Participants were individuals older than 65 years residing in the Washington Heights–Inwood neighborhood of Manhattan. For those who agreed to participate, an in-person interview and a standardized assessment, including a medical history, physical and neurological examination, and neuropsychological battery,31 were completed. Individuals who qualified for initial inclusion in the community study (n = 1401) all had at least one subsequent follow-up evaluation. Participants included 282 (20%) non-Hispanic whites, 462 (33%) African Americans, 646 (46%) Caribbean Hispanics, and 11 (1%) from other ethnic groups. For this study we excluded individuals with other forms of dementia or Parkinson disease. We also excluded individuals with questionable dementia (possible AD). This left 1077 eligible individuals, of whom 169 (16%) had a history of stroke. Of these, DNA from 1013 people was used for genotyping. For patients with AD, the diagnosis was established at a consensus conference of physicians and neuropsychologists and required evidence of cognitive deficit on the neuropsychological battery and evidence of impairment in social or occupational function. When available, all medical records and imaging studies were used in the evaluation, as were data from the initial and follow-up examinations. Patients with AD included individuals with probable AD and those with a Clinical Dementia Rating Scale score of 1.0 or higher.32
POLYMERASE CHAIN REACTION, DNA SEQUENCING, AND GENOTYPING
Oligonucleotide primers for polymerase chain reaction (PCR) amplification of the APP promoter were based on GenBank (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Md) accession D87675 (Table 1 and Figure 1). Fragments were amplified from genomic DNAs using Platinum Taq DNA Polymerase (Invitrogen, Carlsbad, Calif), with cycling parameters of denaturation at 94°C for 30 seconds, annealing at a specific temperature for 45 seconds (primer sequences and temperatures in Table 1), and extension at 72°C for 1 minute. Direct sequencing of the PCR products was performed with dye terminators (ABI PRISM 377 DNA Sequencer; Applied Biosystems, Foster City, Calif). To improve accuracy, the polymorphisms were scored by multiple partially redundant methods. For denaturing high-performance liquid chromatography (DHPLC), sequences were amplified as described herein using primers 2F and 2R, except the final extension in the PCR was followed by denaturation and reannealing to allow heteroduplex formation. Of the PCR product, 15 µL was injected into the WAVE (Transgenomics, Omaha, Neb) DNA fragment analysis system. The DHPLC parameters were calculated using a predictive algorithm supplied by the manufacturer. The +37G/C polymorphism in the heterozygous configuration produced a common DHPLC variant, while heterozygosity for the –9G/C polymorphism produced a rare DHPLC variant. For confirming heterozygotes and detecting homozygotes at the +37G/C polymorphism, the PCR products were resolved on duplicate 1% agarose gels, blotted, and hybridized with 32P end-labeled, allele-specific oligonucleotides ACGCGGAGCAGCGTGCG and ACGCGGAGGAGCGTGCG. End labeling of probes was conducted with  [32P]adenosine triphosphate using T4 polynucleotide kinase (Promega, Madison, Wis), and hybridization conditions have been described.33 For definitive genotyping of the –9G/C polymorphism, the region flanking the polymorphism was amplified by PCR with primers 3F and 3R to generate a 95 base pair (bp) product. This was digested with 2 U of the restriction enzyme AvaI (Roche, Indianapolis, Ind) at 37°C overnight and resolved on 3% Metaphor (BioWhittaker Molecular Applications, Rockland, Md) agarose gels stained with ethidium bromide. The G allele is cleaved to fragments of 57 and 39 bp, distinguishable from the 96 bp fragment representing the C allele.
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Table 1. Oligonucleotidic Sequences and Primer Annealing Conditions*
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Figure 1. Segments of the amyloid precursor protein (APP) promoter examined in this study. Numbering is relative to the transcription start site (TSS). Arrows indicate polymerase chain reaction primers (see Table 1).
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CELL CULTURE AND PROMOTER-REPORTER ASSAYS
A 750-bp promoter fragment, spanning from –573 to +177 relative to the transcription start site, was amplified from templates corresponding to homozygotes for each allele using primers 4F and 4R into which SacI and BglII restriction sites were introduced. The PCR products from individuals with –9G;+37G, –9G;+37C, and –9C;+37G haplotypes were directionally cloned between SacI and BglII sites of the pGL3-Basic vector (Promega) upstream of the luciferase reporter gene. Negative and positive control constructs were pGL3-Basic, lacking any promoter sequences, and pGL3-Control, containing the SV40 promoter and enhancer sequences. A -galactosidase expression plasmid (pSV-beta-galactosidase; Promega) was co-transfected to allow normalization for transfection efficiency. U-87 MG glioma cells (American Type Culture Collection, Rockville, Md) were grown in EMEM medium with Earle's balanced salt solution and 2mM L-glutamine containing 10% heat-inactivated fetal calf serum. The cells were transfected at 70% confluence using FuGene 6 reagent (Roche) according to the manufacturer's specifications. When decreasing amounts of the experimental reporter constructs were used, the total amount of transfected DNA per well was kept constant by adding pGL3-Basic plasmid to achieve a final DNA amount of 1 µg per 35 mm2 plate. The transfected U87 cells were washed with phosphate-buffered isotonic sodium chloride solution and lysed in the plate using 250 µL of Reporter Lysis Buffer (-Galactosidase Enzyme Assay System; Promega). The cell extract was centrifuged for 5 minutes at 10 000g, and the supernatant was collected. An aliquot (20 µL) was used for determining luciferase activity with 100 µL of Luciferase Assay Buffer (Promega) in a Berthold luminometer. -Galactosidase assays (-Galactosidase Assay System; Promega) were performed according to the manufacturer's protocol using 10 to 20 µL of the cell lysate. Luciferase values were then normalized to -galactosidase activity.
STATISTICAL ANALYSIS
Allele frequencies were determined by counting each allele and by calculating sample proportions. For comparison of cases and controls within and across ethnic groups, allele frequencies were calculated for all participants and compared using  2 analysis. Logistic regression was used to compute the odds ratio for the association between AD and the APP promoter polymorphisms. Data were stratified by the presence or absence of an APOE 4 allele and by adjusting for differences in age and education. Logistic regression analyses were conducted separately for each ethnic group. We tested for Hardy-Weinberg equilibrium using a 2 analysis. Multivariate logistic regression was used to compute the odds ratio for the association between AD and APP promoter polymorphisms, adjusting for age, sex, and education.
RESULTS
SEQUENCE POLYMORPHISMS IN THE APP PROMOTER
To screen for APP promoter variants in a tri-ethnic population, the proximal promoter region, from –573 to +125 relative to the transcriptional initiation site, was amplified from genomic DNA of 20 individuals, approximately equally divided among African American, Caribbean Hispanic, and white ethnic groups. We focused on this region since functional analysis and deletion mapping of the human and murine APP promoters have shown it to be sufficient for high level expression in various cell types.18, 20, 22-23 The initial PCR strategy generated overlapping amplicons with primers 1F and 1R and 2F and 2R (Table 1 and Figure 1). Sequencing revealed a single polymorphism: a GC substitution in the first (nontranslated) exon, at position +37. To extend this search to detect rare variants, the amplicon from –308 to +124 (primers 2F and 2R; Table 1 and Figure 1) was generated from genomic DNAs of 1019 individuals, including patients with AD and elderly controls, from the tri-ethnic population sample. These PCR products were analyzed by DHPLC, a highly sensitive method that we have previously employed for detecting allelic variants without a prior knowledge of sequence variation.34 Sequencing of PCR products that produced rare DHPLC variants revealed a second polymorphism, a GC substitution at position –9. No other variants were found. The DHPLC analysis also provided preliminary scoring of heterozygosity at the +37G/C site. For definitive genotyping of the +37G/C polymorphism, the PCR products generated with primers 2F and 2R (Table 1 and Figure 1) were analyzed by Southern blottings followed by hybridization with allele-specific oligonucleotides. Since the –9G/C polymorphism fell within an AvaI restriction site, definitive genotyping of this marker was performed by AvaI digestion of the PCR products made with primers 3F and 3R (Table 1 and Figure 1).
ALLELE FREQUENCIES IN PATIENTS WITH AD AND CONTROLS
Overall allele frequencies for the +37G/C and –9G/C polymorphisms in the combined ethnic groups did not deviate significantly from Hardy-Weinberg equilibrium. The genotype distributions for the +37G/C and –9G/C polymorphisms in patients with AD and controls are given in Table 2 and Table 3. While the –9C allele was not frequent enough to allow statistical conclusions (Table 3), the +37C allele was overrepresented among AD cases overall. This trend was significant only in the univariate analysis of the combined ethnic groups and was not significant after correcting for age, sex, and education (Table 2). Since the frequency of the +37C allele was highest in African Americans, we also analyzed this group separately. This showed a similar trend, but again, the results were not significant in the multivariate analysis (Table 3). Of interest, in both the combined ethnic groups and in the African American group, homozygosity for the +37C allele was more common among patients with AD, and, while the number of participants with this genotype was small, there was an apparent allele dosage effect (Table 3). Also of interest is that the +37C allele was significantly associated with AD in participants lacking an APOE 4 allele (combined ethnic groups), and this remained significant in the multivariate analysis (Table 3). Although the numbers were small, a significant association was not seen in participants with one or more APOE 4 alleles (Table 3).
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Table 2. Allele Frequencies of the -9G/C and +37G/C Polymorphisms and Rates of AD in 3 Ethnic Groups*
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Table 3. Distributions of +37G/C and -9G/C Genotypes in Patients With Alzheimer Disease and Controls*
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Since the allele frequencies differed by ethnicity, we considered the possibility that the observed association of the +37C allele with AD might be trivially explained by genetic admixture in the 3 ethnic groups. Such confounding effects would be expected if the frequencies of AD differed by ethnicity. As given in Table 2, the white group had the lowest rate of AD, but the rates of AD did not differ between the African American and Caribbean Hispanic groups. Since most of the +37C genotypes occurred in the latter 2 groups, genetic admixture is not a likely explanation for the AD associations seen with this marker.
ASSAYS FOR FUNCTIONAL EFFECTS OF THE -9G/C AND +37G/C POLYMORPHISMS
The location of the 2 polymorphisms within regulatory elements in the proximal 5'-flanking region of APP, which accounts for most of the basal transcriptional activity of the promoter,35 suggests that they might influence transcription. Moreover, alignment of human and mouse sequences shows that these polymorphisms were embedded in strongly conserved sequences (Figure 2). A search of the TRANSFAC36 (http://www.gene-regulation.com) and TESS37 (http://www.cbil.upenn.edu/tess/) databases using a 100-nucleotide sequence centered on these changes was performed to determine if the polymorphisms affected predicted transcription factor binding sites. As expected, several potential transcription factor binding sites were altered: 276 sites were detected by TESS with the -9G;+37G sequence, and 266 sites were detected with the -9C;+37C sequence; the TRANSFAC search returned fewer sites and showed a loss of 2 SP1 sites with the -9C;+37C sequence compared with the -9G;+37G sequence. In addition, the -9G/C polymorphism is located 1 bp downstream of the sequences comprising the initiator box, which can determine transcription initiation sites and transcription efficiency.38
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Figure 2. Alignment of the human amyloid precursor protein (APP) promoter sequence spanning the -9G/C and +37G/C polymorphisms with the corresponding murine sequence. Both polymorphisms (bold uppercase letters) are embedded in well-conserved sequences. TSS indicates transcription start site (bold lowercase letters). The murine sequence is from GenBank (National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, Md) accession D10603.
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To test whether these sequence variants could cause differences in APP transcription, we cloned a series of matched 750 bp promoter fragments, containing the common -9G;+37G allele, or each of the 2 variant alleles (-9C;+37G and -9G;+37C), upstream of the luciferase reporter gene. These were transfected into human U-87 astrocytoma cells, a cell type that, like neurons, expresses the APP gene.39-40 The minimal promoter region strongly stimulated expression of the luciferase reporter gene, but luciferase activity was not significantly altered by either of the sequence variants (Figure 3). The fact that linear changes in luciferase were observed paralleling the amount of transfected plasmid DNA confirmed that this assay was not in the saturating range and was therefore giving a valid readout of promoter activity (Figure 3).
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Figure 3. Activity of the amyloid precursor protein (APP) promoter containing the variant alleles in promoter-reporter assays. Plasmid constructs and the amounts of specific plasmid DNA transfected are indicated on the x-axis. The -9C and +37C constructs differ from the control (-9G;+37G) constructs only at these single positions. Although the activity of the -9C allele is slightly higher than the other constructs at the highest plasmid concentration tested, this difference is not observed at lower concentrations. LUC indicates luciferase-catalyzed luminescence; b-gal, the optical density obtained from the -galactosidase reactions.
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COMMENT
In principle, variations in promoter sequences can alter gene expression directly by altering a transcription factor binding site or indirectly by changing the organization of chromatin. Promoter variants with effects on the transcriptional activity of certain human genes have been identified, and genetic association studies have suggested that some of these variants may be disease risk factors. Examples include promoter polymorphisms in the tumor necrosis factor  gene, with effects on transcription that are associated with increased morbidity in infections, including malaria and leishmaniasis41; in the interleukin 6 gene, which is associated with risk of coronary heart disease and systolic blood pressure42-43; in the interferon regulatory factor 1 gene, which can affect allergy and responses to interferons44-45; in the beta-fibrinogen gene, which contributes to regulation of plasma fibrinogen concentration46; and in the insulin gene, which is associated with type I diabetes mellitus.47 In PS1 and APOE, genes that have strong effects on the risk of AD when they contain coding changes, several promoter variants have also been identified. Although consistent findings have yet to emerge from multiple studies, at least one APOE polymorphism, -219G/T, may be associated with altered promoter activity and an altered risk for AD.48-50 Screening of the PS1 upstream region has identified several polymorphisms. Notably, promoter-reporter analysis demonstrated a decrease in promoter activity for 2 of the variant alleles, and 1 of these variants, -48C/T, was associated with early-onset AD.51-52 In another study, polymorphisms in the PS1 promoter and intron 8 were not associated with late-onset AD.53
In the current study, we have identified and characterized 2 genetic variants, a common +37G/C polymorphism and a rare -9G/C variant, in the core sequences of the proximal APP promoter. The +37C allele was weakly associated with AD in a univariate analysis, and there was a suggestion of an allele-dosage effect. However, that association became nonsignificant in the multivariate analysis. A significant association, in the univariate and multivariate analyses, was observed in participants lacking any APOE 4 allele. Although both promoter polymorphisms were embedded in highly conserved sequences, neither the -9G/C nor the +37G/C variants affected basal promoter activity.
Future studies might include expanding the genetic studies to larger cohorts and assessing the functional effect of these polymorphisms on inducible, as opposed to basal, expression of APP messenger RNA. Functional characterization has shown that the region that we examined accounts for the bulk of the basal promoter activity.18-19,35, 38 This region also accounts for inducible expression of APP messenger RNA in response to stimuli and cell stress.15, 54 However, physiological regulation of the APP gene is also influenced by sequences situated more distally. The "APPB" sites, in the more distal promoter region at -1837/-1822 and -2250/-2241, were shown to interact with a complex containing the p50 subunit of NF- B, which is constitutively expressed in neurons and acts as a positive regulator of gene expression.55-56 The distal APP promoter also harbors at least one negative regulatory element, the upstream regulatory element between -2257 and -2234. This binds to an unknown transcription factor present in neural lineage cell lines and in brain extracts.25 These regions may warrant genetic analysis in future studies.
AUTHOR INFORMATION
Accepted for publication June 28, 2002.
Author contributions: Study concept and design (Drs Athan, Lee, Mayeux, and Tycko); acquisition of data (Drs Athan, Mayeux, and Tycko); analysis and interpretation of data (Drs Lee, Mayeux, and Tycko and Mr Arriaga); drafting of the manuscript (Drs Athan, Lee, Mayeux, and Tycko); critical revision of the manuscript for important intellectual content (Drs Athan, Lee, Mayeux, and Tycko); statistical expertise (Drs Lee and Mayeux and Mr Arriaga); obtained funding (Dr Mayeux).
We thank Alejandra Ciappa, MD, and Martha Posada for DNA preparations.
This study was supported by federal grants AG07232 and AG08702 from the National Institutes of Health (Bethesda), the Charles S. Robertson Memorial Gift for Alzheimer's Disease Research from the Banbury Fund, and the Blanchette Hooker Rockefeller Foundation.
Corresponding author and reprints: Richard P. Mayeux, MD, MPH, Gertrude H. Sergievsky Center, 630 W 168th St, Columbia University, New York, NY 10032 (e-mail: rpm2{at}columbia.edu).
From the Taub Institute for Research on Alzheimer's Disease and the Aging Brain (Drs Athan, Mayeux, and Tycko), Gertrude H. Sergievsky Center (Drs Lee and Mayeux and Mr Arriaga), and Departments of Neurology (Dr Mayeux) and Pathology (Dr Tycko), Columbia University College of Physicians and Surgeons, New York, NY.
REFERENCES
| |
1. Selkoe DJ. Presenilin, Notch, and the genesis and treatment of Alzheimer's disease. Proc Natl Acad Sci U S A. 2001;98:11039-11041.
FREE FULL TEXT
2. Ashall F, Goate AM. Role of the beta-amyloid precursor protein in Alzheimer's disease. Trends Biochem Sci. 1994;19:42-46.
FULL TEXT
|
ISI
| PUBMED
3. Borchelt DR, Thinakaran G, Eckman CB, et al. Familial Alzheimer's disease-linked presenilin 1 variants elevate A1-42/1-40 ratio in vitro and in vivo. Neuron. 1996;17:1005-1013.
FULL TEXT
|
ISI
| PUBMED
4. St George-Hyslop PH. Genetic factors in the genesis of Alzheimer's disease. Ann N Y Acad Sci. 2000;924:1-7.
FULL TEXT
|
ISI
| PUBMED
5. Roses AD. Apolipoprotein E, a gene with complex biological interactions in the aging brain. Neurobiol Dis. 1997;4:170-185.
FULL TEXT
|
ISI
| PUBMED
6. Gandy S, Petanceska S. Regulation of Alzheimer -amyloid precursor trafficking and metabolism. Biochim Biophys Acta. 2000;1502:44-52.
PUBMED
7. Gentleman SM, Nash MJ, Sweeting CJ, et al. Beta-amyloid precursor protein (beta APP) as a marker for axonal injury after head injury. Neurosci Lett. 1993;160:139-144.
FULL TEXT
|
ISI
| PUBMED
8. Malherbe P, Richards JG, Martin JR, et al. Lack of -amyloidosis in transgenic mice expressing low levels of familial Alzheimer's disease missense mutations. Neurobiol Aging. 1996;17:205-214.
FULL TEXT
|
ISI
| PUBMED
9. van Leuven F. Single and multiple transgenic mice as models for Alzheimer's disease. Prog Neurobiol. 2000;61:305-312.
FULL TEXT
|
ISI
| PUBMED
10. Schupf N, Patel B, Silverman W, et al. Elevated plasma amyloid -peptide 1-42 and onset of dementia in adults with Down syndrome. Neurosci Lett. 2001;301:199-203.
FULL TEXT
|
ISI
| PUBMED
11. Wisniewski KE, Wisniewski HM, Wen GY. Occurrence of neuropathological changes and dementia of Alzheimer's disease in Down's syndrome. Ann Neurol. 1985;17:278-282.
FULL TEXT
|
ISI
| PUBMED
12. Kida E, Choi-Miura NH, Wisniewski KE. Deposition of apolipoproteins E and J in senile plaques is topographically determined in both Alzheimer's disease and Down's syndrome brain. Brain Res. 1995;685:211-216.
FULL TEXT
|
ISI
| PUBMED
13. Hyman BT. Down syndrome and Alzheimer disease. Prog Clin Biol Res. 1992;379:123-142.
PUBMED
14. Zigman WB, Schupf N, Sersen E, Silverman W. Prevalence of dementia in adults with and without Down syndrome. Am J Ment Retard. 1996;100:403-412.
ISI
| PUBMED
15. Goldgaber D, Harris HW, Hla T, et al. Interleukin 1 regulates synthesis of amyloid beta-protein precursor mRNA in human endothelial cells. Proc Natl Acad Sci U S A. 1989;86:7606-7610.
FREE FULL TEXT
16. Lahiri DK, Robakis NK. The promoter activity of the gene encoding Alzheimer beta-amyloid precursor protein (APP) is regulated by two blocks of upstream sequences. Brain Res Mol Brain Res. 1991;9:253-257.
PUBMED
17. Izumi R, Yamada T, Yoshikai S, et al. Positive and negative regulatory elements for the expression of the Alzheimer's disease amyloid precursor-encoding gene in mouse. Gene. 1992;112:189-195.
FULL TEXT
|
ISI
| PUBMED
18. Quitschke WW, Goldgaber D. The amyloid beta-protein precursor promoter: a region essential for transcriptional activity contains a nuclear factor binding domain. J Biol Chem. 1992;267:17362-17368.
FREE FULL TEXT
19. Quitschke WW. Two nuclear factor binding domains activate expression from the human amyloid beta-protein precursor promoter. J Biol Chem. 1994;269:21229-21233.
FREE FULL TEXT
20. Trejo J, Massamiri T, Deng T, et al. A direct role for protein kinase C and the transcription factor Jun/AP-1 in the regulation of the Alzheimer's beta-amyloid precursor protein gene. J Biol Chem. 1994;269:21682-21690.
FREE FULL TEXT
21. Dewji NN, Do C, Bayney RM. Transcriptional activation of Alzheimer's -amyloid precursor protein gene by stress. Brain Res Mol Brain Res. 1995;33:245-253.
PUBMED
22. Lahiri DK, Nall C. Promoter activity of the gene encoding the beta-amyloid precursor protein is up-regulated by growth factors, phorbol ester, retinoic acid and interleukin-1. Brain Res Mol Brain Res. 1995;32:233-240.
PUBMED
23. Bourbonniere M, Nalbantoglu J. The helix-loop-helix transcription factor USF interacts with the basal promoter of human amyloid precursor protein. Brain Res Mol Brain Res. 1996;35:304-308.
PUBMED
24. Ringheim GE, Szczepanik AM, Petko W, et al. Enhancement of beta-amyloid precursor protein transcription and expression by the soluble interleukin-6 receptor/interleukin-6 complex. Brain Res Mol Brain Res. 1998;55:35-44.
PUBMED
25. Lahiri DK, Nall C, Ge YW. Promoter activity of the beta-amyloid precursor protein gene is negatively modulated by an upstream regulatory element. Brain Res Mol Brain Res. 1999;71:32-41.
PUBMED
26. Ruiz-Leon Y, Pascual A. Brain-derived neurotrophic factor stimulates -amyloid gene promoter activity by a Ras-dependent/AP-1-independent mechanism in SH-SY5Y neuroblastoma cells. J Neurochem. 2001;79:278-285.
FULL TEXT
|
ISI
| PUBMED
27. Liddell MB, Bayer AJ, Owen MJ. No evidence that common allelic variation in the amyloid precursor protein (APP) gene confers susceptibility to Alzheimer's disease. Hum Mol Genet. 1995;4:853-858.
FREE FULL TEXT
28. Theuns J, Van Broeckhoven C. Transcriptional regulation of Alzheimer's disease genes: implications for susceptibility. Hum Mol Genet. 2000;9:2383-2394.
FREE FULL TEXT
29. Wavrant-De Vrieze F, Crook R, Holmans P, et al. Genetic variability at the amyloid- precursor protein locus may contribute to the risk of late-onset Alzheimer's disease. Neurosci Lett. 1999;269:67-70.
FULL TEXT
|
ISI
| PUBMED
30. Li L, Perry R, Wu J, et al. Polymorphic tetranucleotide repeat site within intron 7 of the -amyloid precursor protein gene and its lack of association with Alzheimer's disease. Hum Genet. 1998;103:86-89.
FULL TEXT
|
ISI
| PUBMED
31. Stern Y, Andrews H, Pittman J, et al. Diagnosis of dementia in a heterogeneous population: development of a neuropsychological paradigm-based diagnosis of dementia and quantified correction for the effects of education. Arch Neurol. 1992;49:453-460.
FREE FULL TEXT
32. Hughes CP, Berg L, Danziger WL, Coben LA, Martin RL. A new clinical scale for the staging of dementia. Br J Psychiatry. 1982;140:566-572.
FREE FULL TEXT
33. Tycko B, Feng L, Nguyen L, et al. Polymorphisms in the human apolipoprotein-J/clusterin gene: ethnic variation and distribution in Alzheimer's disease. Hum Genet. 1996;98:430-436.
FULL TEXT
|
ISI
| PUBMED
34. Athan ES, Williamson J, Ciappa A, et al. A founder mutation in presenilin 1 causing early-onset Alzheimer disease in unrelated Caribbean Hispanic families. JAMA. 2001;286:2257-2263.
FREE FULL TEXT
35. Lahiri DK, Song W, Ge YW. Analysis of the 5'-flanking region of the -amyloid precursor protein gene that contributes to increased promoter activity in differentiated neuronal cells. Molecular Brain Res. 2000;77:185-198.
PUBMED
36. Wingender E, Chen X, Hehl R, et al. TRANSFAC: an integrated system for gene expression regulation. Nucleic Acids Res. 2000;28:316-319.
FREE FULL TEXT
37. Schug J, Overton GC. TESS: transcription elementsearch software on the WWW: technical report CBIL-TR-1997-1001-V0.0 of the Computational Biology and Informatics Laboratory. Philadelphia: University of Pennsylvania; 1997.
38. Quitschke WW, Matthews JP, Kraus RJ, Vostrov AA. The initiator element and proximal upstream sequences affect transcriptional activity and start site selection in the amyloid -protein precursor promoter. J Biol Chem. 1996;271:22231-22239.
FREE FULL TEXT
39. Nakagawa T, Kabuto M, Kubota T, et al. Production of amyloid beta protein precursor as a proteinase inhibitor by human astrocytic tumors. Anticancer Res. 1999;19:2963-2968.
ISI
| PUBMED
40. Carlson CD, Czilli DL, Gitter BD. Regulation of amyloid precursor protein processing by A in human glioma cells. Neurobiol Aging. 2000;21:747-756.
FULL TEXT
|
ISI
| PUBMED
41. Wilson AG, Symons JA, McDowell TL, et al. Effects of a polymorphism in the human tumor necrosis factor promoter on transcriptional activation. Proc Natl Acad Sci U S A. 1997;94:3195-3199.
FREE FULL TEXT
42. Rauramaa R, Vaisanen SB, Luong LA, et al. Stromelysin-1 and interleukin-6 gene promoter polymorphisms are determinants of asymptomatic carotid artery atherosclerosis. Arterioscler Thromb Vasc Biol. 2000;20:2657-2662.
FREE FULL TEXT
43. Humphries SE, Luong LA, Ogg MS, et al. The interleukin-6-174 G/C promoter polymorphism is associated with risk of coronary heart disease and systolic blood pressure in healthy men. Eur Heart J. 2001;22:2243-2252.
FREE FULL TEXT
44. Nakao F, Ihara K, Kusuhara K, et al. Association of IFN- and IFN regulatory factor 1 polymorphisms with childhood atopic asthma. J Allergy Clin Immunol. 2001;107:499-504.
FULL TEXT
|
ISI
| PUBMED
45. Saito H, Tada S, Ebinuma H, et al. Interferon regulatory factor 1 promoter polymorphism and response to type 1 interferon. J Cell Biochem. 2001;81(suppl):191-200.
46. van ‘t Hooft FM, von Bahr SJ, Silveira A, et al. Two common, functional polymorphisms in the promoter region of the beta-fibrinogen gene contribute to regulation of plasma fibrinogen concentration. Arterioscler Thromb Vasc Biol. 1999;19:3063-3070.
FREE FULL TEXT
47. Bennett ST, Wilson AJ, Esposito L, et al. Insulin VNTR allele-specific effect in type 1 diabetes depends on identity of untransmitted paternal allele: the IMDIAB Group. Nat Genet. 1997;17:350-352.
FULL TEXT
|
ISI
| PUBMED
48. Lambert JC, Berr C, Pasquier F, et al. Pronounced impact of Th1/E47cs mutation compared with -491 AT mutation on neural APOE gene expression and risk of developing Alzheimer's disease. Hum Mol Genet. 1998;7:1511-1516.
FREE FULL TEXT
49. Rebeck GW, Cheung BS, Growdon WB, et al. Lack of independent associations of apolipoprotein E promoter and intron 1 polymorphisms with Alzheimer's disease. Neurosci Lett. 1999;272:155-158.
FULL TEXT
|
ISI
| PUBMED
50. Heijmans BT, Slagboom PE, Gussekloo J, et al. Association of APOE varepsilon2/varepsilon3/varepsilon4 and promoter gene variants with dementia but not cardiovascular mortality in old age. Am J Med Genet. 2002;107:201-208.
FULL TEXT
|
ISI
| PUBMED
51. van Duijn CM, Cruts M, Theuns J, et al. Genetic association of the presenilin-1 regulatory region with early-onset Alzheimer's disease in a population-based sample. Eur J Hum Genet. 1999;7:801-806.
FULL TEXT
|
ISI
| PUBMED
52. Theuns J, Del-Favero J, Dermaut B, et al. Genetic variability in the regulatory region of presenilin 1 associated with risk for Alzheimer's disease and variable expression. Hum Mol Genet. 2000;9:325-331.
FREE FULL TEXT
53. Dermaut B, Roks G, Theuns J, et al. Variable expression of presenilin 1 is not a major determinant of risk for late-onset Alzheimer's disease. J Neurol. 2001;248:935-939.
FULL TEXT
|
ISI
| PUBMED
54. Querfurth HW, Jiang J, Xia W, Selkoe DJ. Enhancer function and novel DNA binding protein activity in the near upstream APP gene promoter. Gene. 1999;232:125-141.
FULL TEXT
|
ISI
| PUBMED
55. Grilli M, Goffi F, Memo M, Spano P. Interleukin-1 and glutamate activate the NF-B/Rel binding site from the regulatory region of the amyloid precursor protein gene in primary neuronal cultures. J Biol Chem. 1996;271:15002-15007.
FREE FULL TEXT
56. Grilli M, Ribola M, Alberici A, et al. Identification and characterization of a B/Rel binding site in the regulatory region of the amyloid precursor protein gene. J Biol Chem. 1995;270:26774-26777.
FREE FULL TEXT
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