Abstract
BACE1, which cleaves the amyloid precursor protein, is the rate-limiting enzyme for β-amyloid peptide production, leading to the pathogenesis of Alzheimer's disease (AD). A high plasma level of homocysteine, acting as a potent methyltransferase inhibitor, is assumed to be a risk factor for AD onset. Using the demethylating drug 5-aza-2'-deoxycytidine (5-Aza), we tested whether and how BACE1 expression is regulated in mouse BV-2 microglial cells. 5-Aza increased both BACE1 mRNA and protein levels in a dose-dependent manner. Bisulfite-sequencing analysis revealed that two CpG sites at positions +298 and +351 in the 5'-untranslated region (5'-UTR) of the BACE1 gene were specifically demethylated in BV-2 cells treated with 5-Aza. In silico analysis showed that the +351 site is the STAT3/CTCF-binding site; the function of the +298 site has not been identified. To assess whether these two CpG sites play an important role in 5-Aza-induced transcriptional activation of BACE1, we constructed a BACE1 gene promoter including the 5'-UTR (-1136 to +500) fused to a CpG-free luciferase gene (pCpGL-BACE1) and its mutant pCpGL-BACE1-AA, which has substituted CG dinucleotides at the two CpG sites of pCpGL-BACE1 to AA. Promoter analysis showed a significant decrease (~30%) in the activity of pCpGL-BACE1-AA compared with that of pCpGL-BACE1. Furthermore, in vitro methylation of these two reporter constructs showed a complete silencing of their promoter activities. Our data demonstrate that BACE1 gene expression is regulated by DNA methylation of at least two CpG sites at positions +298 and +351 in the 5'-UTR in BV-2 microglial cells.
| Original language | English |
|---|---|
| Pages (from-to) | 387-392 |
| Number of pages | 6 |
| Journal | Biochemical and Biophysical Research Communications |
| Volume | 417 |
| Issue number | 1 |
| DOIs | |
| Publication status | Published - 2012 Jan 6 |
Fingerprint
Keywords
- 5′-Untranslated region
- Alzheimer's disease
- BACE1
- DNA methylation
- Microglial cells
ASJC Scopus subject areas
- Biophysics
- Biochemistry
- Molecular Biology
- Cell Biology
Cite this
DNA methylation of the 5′-untranslated region at +298 and +351 represses BACE1 expression in mouse BV-2 microglial cells. / Byun, Catherine Jeonghae; Seo, Jungwon; Jo, Sangmee Ahn; Park, Yoon Jung; Klug, Maja; Rehli, Michael; Park, Moon Ho; Jo, Inho.
In: Biochemical and Biophysical Research Communications, Vol. 417, No. 1, 06.01.2012, p. 387-392.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - DNA methylation of the 5′-untranslated region at +298 and +351 represses BACE1 expression in mouse BV-2 microglial cells
AU - Byun, Catherine Jeonghae
AU - Seo, Jungwon
AU - Jo, Sangmee Ahn
AU - Park, Yoon Jung
AU - Klug, Maja
AU - Rehli, Michael
AU - Park, Moon Ho
AU - Jo, Inho
PY - 2012/1/6
Y1 - 2012/1/6
N2 - BACE1, which cleaves the amyloid precursor protein, is the rate-limiting enzyme for β-amyloid peptide production, leading to the pathogenesis of Alzheimer's disease (AD). A high plasma level of homocysteine, acting as a potent methyltransferase inhibitor, is assumed to be a risk factor for AD onset. Using the demethylating drug 5-aza-2'-deoxycytidine (5-Aza), we tested whether and how BACE1 expression is regulated in mouse BV-2 microglial cells. 5-Aza increased both BACE1 mRNA and protein levels in a dose-dependent manner. Bisulfite-sequencing analysis revealed that two CpG sites at positions +298 and +351 in the 5'-untranslated region (5'-UTR) of the BACE1 gene were specifically demethylated in BV-2 cells treated with 5-Aza. In silico analysis showed that the +351 site is the STAT3/CTCF-binding site; the function of the +298 site has not been identified. To assess whether these two CpG sites play an important role in 5-Aza-induced transcriptional activation of BACE1, we constructed a BACE1 gene promoter including the 5'-UTR (-1136 to +500) fused to a CpG-free luciferase gene (pCpGL-BACE1) and its mutant pCpGL-BACE1-AA, which has substituted CG dinucleotides at the two CpG sites of pCpGL-BACE1 to AA. Promoter analysis showed a significant decrease (~30%) in the activity of pCpGL-BACE1-AA compared with that of pCpGL-BACE1. Furthermore, in vitro methylation of these two reporter constructs showed a complete silencing of their promoter activities. Our data demonstrate that BACE1 gene expression is regulated by DNA methylation of at least two CpG sites at positions +298 and +351 in the 5'-UTR in BV-2 microglial cells.
AB - BACE1, which cleaves the amyloid precursor protein, is the rate-limiting enzyme for β-amyloid peptide production, leading to the pathogenesis of Alzheimer's disease (AD). A high plasma level of homocysteine, acting as a potent methyltransferase inhibitor, is assumed to be a risk factor for AD onset. Using the demethylating drug 5-aza-2'-deoxycytidine (5-Aza), we tested whether and how BACE1 expression is regulated in mouse BV-2 microglial cells. 5-Aza increased both BACE1 mRNA and protein levels in a dose-dependent manner. Bisulfite-sequencing analysis revealed that two CpG sites at positions +298 and +351 in the 5'-untranslated region (5'-UTR) of the BACE1 gene were specifically demethylated in BV-2 cells treated with 5-Aza. In silico analysis showed that the +351 site is the STAT3/CTCF-binding site; the function of the +298 site has not been identified. To assess whether these two CpG sites play an important role in 5-Aza-induced transcriptional activation of BACE1, we constructed a BACE1 gene promoter including the 5'-UTR (-1136 to +500) fused to a CpG-free luciferase gene (pCpGL-BACE1) and its mutant pCpGL-BACE1-AA, which has substituted CG dinucleotides at the two CpG sites of pCpGL-BACE1 to AA. Promoter analysis showed a significant decrease (~30%) in the activity of pCpGL-BACE1-AA compared with that of pCpGL-BACE1. Furthermore, in vitro methylation of these two reporter constructs showed a complete silencing of their promoter activities. Our data demonstrate that BACE1 gene expression is regulated by DNA methylation of at least two CpG sites at positions +298 and +351 in the 5'-UTR in BV-2 microglial cells.
KW - 5′-Untranslated region
KW - Alzheimer's disease
KW - BACE1
KW - DNA methylation
KW - Microglial cells
UR - http://www.scopus.com/inward/record.url?scp=84855762409&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84855762409&partnerID=8YFLogxK
U2 - 10.1016/j.bbrc.2011.11.123
DO - 10.1016/j.bbrc.2011.11.123
M3 - Article
C2 - 22166205
AN - SCOPUS:84855762409
VL - 417
SP - 387
EP - 392
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 1
ER -