Cholesterol 7 alpha-hydroxylase
| cytochrome P450, family 7, subfamily A, polypeptide 1
|
| Identifiers
|
| Symbol
| CYP7A1
|
| Alt. Symbols
| CYP7
|
| Entrez
| 1581
|
| HUGO
| 2651
|
| OMIM
| 118455
|
| RefSeq
| NM_000780
|
| UniProt
| P22680
|
| Other data
|
| EC number
| 1.14.13.17
|
| Locus
| Chr. 8 q11-q12
|
Cholesterol 7 alpha-hydroxylase (CYP7A1), the rate-limiting enzyme in the synthesis of bile acid from cholesterol, catalyzing the formation of 7-alpha-hydroxycholesterol.
It is downregulated by Sterol regulatory element binding proteins (SREBP) when plasma cholesterol levels are low. It is upregulated by the nuclear receptor LXR (liver X receptor) when cholesterol (specifically - oxysterol) levels are high.[1] The effect of this upregulation is to increase the production of bile acids and reduce the level of cholesterol in hepatocytes.
References
- ^ Chawla A, Saez E, Evans RM (2000). "Don't know much bile-ology". Cell 103: 1–4.
| Oxidoreductases: dioxygenases, including steroid hydroxylases (EC 1.14) |
|---|
| 1.14.11 - 2-oxoglutarate | Prolyl hydroxylase - Lysyl hydroxylase |
|---|
| 1.14.13 - NADH or NADPH | Flavin-containing monooxygenase - Nitric oxide synthase - Cholesterol 7 alpha-hydroxylase - Methane monooxygenase - 3A4 -51A1 |
|---|
| 1.14.14 - reduced flavin or flavoprotein | 19A1 - 2D6 - 2E1 |
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| 1.14.15 - reduced iron-sulfur protein | 11B1 - 11B2 - 11A1 |
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| 1.14.16 - reduced pteridine | Phenylalanine hydroxylase - Tyrosine hydroxylase - Tryptophan hydroxylase |
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| 1.14.17 - reduced ascorbate | Dopamine beta hydroxylase |
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| 1.14.18-19 - other | Tyrosinase - Stearoyl-CoA desaturase-1 |
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| 1.14.99 - miscellaneous | Cyclooxygenase - Heme oxygenase (HMOX1) - Squalene monooxygenase - 17A1 - 21A2 |
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| Cytochromes, oxygenases: cytochrome P450 (EC 1.14) |
|---|
| CYP1 | A1, A2, B1 |
|---|
| CYP2 | A6, A7, A13, B6, C8, C9, C18, C19, D6, E1, F1, J2, R1, S1, U1, W1 |
|---|
| CYP3 | A4, A5, A7, A43 |
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| CYP4 | A11, A22, B1, F2, F3, F8, F11, F12, F22, V2, X1, Z1 |
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| CYP5-20 | CYP5 (A1) - CYP7 (A1, B1) - CYP8 (A1, B1) - CYP11 (A1, B1, B2) - CYP17 (A1) - CYP19 (A1) - CYP20 (A1) |
|---|
| CYP21-51 | CYP21 (A2) - CYP24 (A1) - CYP26 (A1, B1, C1) - CYP27 (A1, B1, C1) - CYP39 (A1) - CYP46 (A1) - CYP51 (A1) |
|---|
| Metabolism: lipid metabolism |
|---|
| Lipid production | Acetyl-CoA carboxylase - Fatty acid synthesis: Beta-ketoacyl-ACP synthase - Β-Ketoacyl ACP reductase - 3-Hydroxyacyl ACP dehydrase - Enoyl ACP reductase unsaturated (Enoyl CoA isomerase, 2,4 Dienoyl-CoA reductase) - odd chain (Propionyl-CoA carboxylase) - Fatty acid synthase - Long fatty acyl CoA synthetase |
|---|
| Lipid degradation | Acyl transport: Carnitine palmitoyltransferase I - Carnitine-acylcarnitine translocase - Carnitine palmitoyltransferase II Beta oxidation: Acyl CoA dehydrogenase (ACADL, ACADM, ACADS, ACADVL) - Enoyl-CoA hydratase - 3-Hydroxyacyl CoA dehydrogenase - Acetyl-CoA C-acyltransferase - Mitochondrial trifunctional protein Ketogenesis: HMG-CoA synthase - HMG-CoA lyase - Other: Malonyl-CoA decarboxylase |
|---|
| Phospholipids | Diacylglycerol kinase |
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| Steroids | HMG-CoA reductase - Farnesyl-diphosphate farnesyltransferase - Squalene monooxygenase - Lanosterol synthase - CYP51A1 |
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| Prostanoids | Cyclooxygenase - Thromboxane-A synthase - Prostacyclin synthase - Prostaglandin E synthase - Prostaglandin D2 synthase |
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| Leukotrienes | Arachidonate 5-lipoxygenase - 5-Lipoxygenase activating protein - Leukotriene A4 hydrolase - Leukotriene C4 synthase |
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| Bile acids | Cholesterol 7 alpha-hydroxylase |
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