Center for Bioinformatics
Oxidoreductases | Transferases | Hydrolases | Lyases | Isomerases | Ligases

Basic Information

Enzyme Number

1.14.13.17

Official Name

cholesterol 7alpha-monooxygenase

Name from literature

7alpha-hydroxylase

Pathway from literature

bile acid synthesis/the synthesis of the cofactor for PAH(phenylalanine hydroxylase )

Pathway from KEGG

Lipid Metabolism; Bile acid biosynthesis; map00120

Cellular Processes; Endocrine System; PPAR signaling pathway; map03320

Organisms

Mouse (10090)

Genome localization

4 A1[13122 ],

Comments

A heme-thiolate protein (P-450).

Rate-limiting Description

"Intriguingly, while the expression of Cyp8b1 is almost extinguished in the livers of mice that lack LRH-1, the expression of the rate-limiting enzyme of BA synthesis, i.e., Cyp7a1, remains unchanged." (17908794)

"This study aimed to evaluate the expression pattern within the liver architecture of the rate-limiting enzyme of the neutral pathway, cholesterol 7alpha-hydroxylase (Cyp7a1), and sterol 12alpha-hydroxylase (Cyp8b1), the enzyme necessary for the synthesis of cholic acid." (17237956)

Regulatory Information

Upstream transcription factor

19017;15378;20181

Regulatory type

Detail

feedback;

"Feedback regulation of the rate-limiting biosynthetic enzyme CYP7A1 is lost in Cyp8b1(-/-) mice, causing expansion of the bile acid pool and alterations in cholesterol metabolism." (12393855)

transcriptional factor;PGC-1alpha(19017)

"CYP7A1 is activated by PGC-1alpha" (14522988)

transcriptional factor;"HNF-4(15378),PGC-1alpha(19017)"

"SREBP-1c functions as a non-DNA-binding inhibitor and mediates, in part, suppression of Cyp7a1 by blocking functional interaction of HNF-4 and PGC-1alpha" (17636037)

transcriptional factor;PGC-1alpha(19017)

"PGC-1alpha is an important co-activator for LRH-1 and that SHP targets the interaction between LRH-1 and PGC-1alpha to inhibit CYP7A1 expression." (18385139)

transcriptional factor;"Thyroid hormone receptors(21833,21834),retinoid X receptor(20181) "

"One site is a DR-0, which is an unusual type of TR response element, and the other consists of only a single recognizable half site that is required for TR/retinoid X receptor (RXR) binding. These two independent TR-binding sites are closely spaced and both are required for full induction of the CYP7A1 promoter by thyroid hormone, although the DR-0 site was more crucial." (16899449)

Gene ontology

Gene ontology

GO:0006707 (P) cholesterol catabolic process [Q64505 ];
GO:0020037 (F) heme binding [Q64505 ];
GO:0008123 (F) cholesterol 7-alpha-monooxygenase activity [Q64505 ];
GO:0005506 (F) iron ion binding [Q64505 ];
GO:0005789 (C) endoplasmic reticulum membrane [Q64505 ];
GO:0009055 (F) electron carrier activity [Q64505 ];
GO:0005792 (C) microsome [Q64505 ];
GO:0055114 (P) oxidation reduction [Q64505 ];

Subcellular localization

Localization

endoplasmic reticulum [Q64505 ];

microsome [Q64505 ];

membrane [Q64505 ];

Links

SwissProt

Q64505

Entrez Gene

13122



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  Last Modified: 2009-03-24  
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