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From Proteopedia
A Chemical, Genetic, and Structural Analysis of the nuclear bile acid receptor FXR
Structural highlights
Function[NR1H4_HUMAN] Ligand-activated transcription factor. Receptor for bile acids such as chenodeoxycholic acid, lithocholic acid and deoxycholic acid. Represses the transcription of the cholesterol 7-alpha-hydroxylase gene (CYP7A1) through the induction of NR0B2 or FGF19 expression, via two distinct mechanisms. Activates the intestinal bile acid-binding protein (IBABP). Activates the transcription of bile salt export pump ABCB11 by directly recruiting histone methyltransferase CARM1 to this locus.[1] [2] [3] [4] [5] [6] [7] [8] Evolutionary Conservation Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf. Publication Abstract from PubMedThe farnesoid X receptor (FXR) functions as a bile acid (BA) sensor coordinating cholesterol metabolism, lipid homeostasis, and absorption of dietary fats and vitamins. However, BAs are poor reagents for characterizing FXR functions due to multiple receptor independent properties. Accordingly, using combinatorial chemistry we evolved a small molecule agonist termed fexaramine with 100-fold increased affinity relative to natural compounds. Gene-profiling experiments conducted in hepatocytes with FXR-specific fexaramine versus the primary BA chenodeoxycholic acid (CDCA) produced remarkably distinct genomic targets. Highly diffracting cocrystals (1.78 A) of fexaramine bound to the ligand binding domain of FXR revealed the agonist sequestered in a 726 A(3) hydrophobic cavity and suggest a mechanistic basis for the initial step in the BA signaling pathway. The discovery of fexaramine will allow us to unravel the FXR genetic network from the BA network and selectively manipulate components of the cholesterol pathway that may be useful in treating cholesterol-related human diseases. A chemical, genetic, and structural analysis of the nuclear bile acid receptor FXR.,Downes M, Verdecia MA, Roecker AJ, Hughes R, Hogenesch JB, Kast-Woelbern HR, Bowman ME, Ferrer JL, Anisfeld AM, Edwards PA, Rosenfeld JM, Alvarez JG, Noel JP, Nicolaou KC, Evans RM Mol Cell. 2003 Apr;11(4):1079-92. PMID:12718892[9] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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Categories: Human | Alvarez, J G.A | Anisfeld, A M | Bowman, M E | Downes, M | Edwards, P A | Evans, R M | Ferrer, J L | Hogenesch, J B | Hughes, R | Kast-Woelbern, H R | Nicolaou, K C | Noel, J P | Roecker, A J | Rosenfeld, J M | Verdecia, M A | Ligand binding domain | Nuclear receptor | Transcription
