Induction of apolipoprotein E expression by TR4 orphan nuclear receptor via 5' proximal promoter region.
Publication/Presentation Date
3-4-2005
Abstract
While other plasma lipoproteins are exclusively expressed in liver and intestine, apoliprotein E (apoE) is ubiquitously synthesized in many tissues. To understand the molecular mechanism of non-tissue-specific apoE expression, we tested the testicular orphan receptor 4 (TR4) effect on apoE expression in different cell lines, such as HepG2, COS-1, and H1299 cells. Gel shift assay and 5' promoter activity analyses identified one distinct hormone response element (TR4RE-DR0-apoE at -303 to -292 bp) that binds to TR4 and results in full induction of apoE gene transcription. TR4 also forms a complex with Sp1 to synergistically induce apoE expression via a region containing the TR4RE-DR0-apoE and the Sp1 binding site (-169 to -140 bp). Induction of apoE expression by TR4 was also confirmed at the mRNA and protein levels in H1299 cells. Together, our data demonstrate that TR4 can enhance apoE gene expression via binding to TR4RE-DR0 in apoE 5' promoter and this TR4 binding is essential for synergistic interaction with another transcription factor, Sp1.
Volume
328
Issue
1
First Page
85
Last Page
90
ISSN
0006-291X
Published In/Presented At
Kim, E., Yang, Z., Liu, N. C., & Chang, C. (2005). Induction of apolipoprotein E expression by TR4 orphan nuclear receptor via 5' proximal promoter region. Biochemical and biophysical research communications, 328(1), 85–90. https://doi.org/10.1016/j.bbrc.2004.12.146
Disciplines
Medicine and Health Sciences
PubMedID
15670754
Department(s)
Department of Pathology and Laboratory Medicine
Document Type
Article