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miR-199a-5p inhibits the expression of ABCB11 in obstructive cholestasis
- Source :
- The Journal of Biological Chemistry
- Publication Year :
- 2021
-
Abstract
- ATP-binding cassette, sub-family B member 11 (ABCB11) is an efflux transporter for bile acids on the liver canalicular membrane. The expression of this transporter is reduced in cholestasis; however, the mechanisms contributing to this reduction are unclear. In this study, we sought to determine whether miR-199a-5p contributes to the depletion of ABCB11/Abcb11 in cholestasis in mice. In a microRNA (miRNA) screen of mouse liver after common bile duct ligation (CBDL), we found that miR-199a-5p was significantly upregulated by approximately 4-fold. In silico analysis predicted that miR-199a-5p would target the 3'-untranslated region (3'-UTR) of ABCB11/Abcb11 mRNA. The expression of ABCB11-3'-UTR luciferase construct in Huh-7 cells was markedly inhibited by cotransfection of a miRNA-199a-5p mimic, which was reversed by a miRNA-199a-5p mimic inhibitor. We also show treatment of mice after CBDL with the potent nuclear receptor FXR agonist obeticholic acid (OCA) significantly increased Abcb11 mRNA and protein and decreased miR-199a-5p expression. Computational mapping revealed a well-conserved FXR-binding site (FXRE) in the promoter of the gene encoding miR-199a-5, termed miR199a-2. Electromobility shift, chromatin immunoprecipitation, and miR199a-2 promoter-luciferase assays confirmed that this binding site was functional. Finally, CBDL in mice led to depletion of nuclear repressor NcoR1 binding at the miR199a-2 promoter, which facilitates transcription of miR199a-2. In CBDL mice treated with OCA, NcoR1 recruitment to the miR199a-2 FXRE was maintained at levels found in sham operated mice. In conclusion, we demonstrate that miR-199a-5p is involved in regulating ABCB11/Abcb11 expression, is aberrantly upregulated in obstructive cholestasis, and is downregulated by the FXR agonist obeticholic acid.
- Subjects :
- Male
ABCC2, ATP-binding cassette sub-family C member 2
RXR, retinoid X receptor
Repressor
Retinoid X receptor
Chenodeoxycholic Acid
ATP-dependent efflux transporter
Biochemistry
FXR, arnesoid X receptor
miR, microRNA
chemistry.chemical_compound
Mice
Cholestasis
MRP2, multidrug resistance-associated protein 2
medicine
Animals
Nuclear Receptor Co-Repressor 1
canalicular
SMRT, silencing mediator of retinoic acid and thyroid hormone receptor
ABCB11
Molecular Biology
Nuclear receptor co-repressor 1
ATP Binding Cassette Transporter, Subfamily B, Member 11
BSEP, bile salt export pump
Mice, Knockout
bile acids
microRNA
Multidrug resistance-associated protein 2
NCOR1, nuclear receptor corepressor 1
Obeticholic acid
Cell Biology
ABCB11, ATP-binding cassette sub-family B member 11
medicine.disease
Molecular biology
Disease Models, Animal
MicroRNAs
Nr1h4, nuclear receptor subfamily 1, group H, member 4
chemistry
Gene Expression Regulation
OCA, obeticholic acid
Farnesoid X receptor
Research Article
biliary
Subjects
Details
- ISSN :
- 1083351X
- Volume :
- 297
- Issue :
- 6
- Database :
- OpenAIRE
- Journal :
- The Journal of biological chemistry
- Accession number :
- edsair.doi.dedup.....e1a013e773a28d1858652b76631c178c