Cytochrome P450 1A2 (abbreviated CYP1A2), a member of the cytochrome P450 mixed-function oxidase system, is involved in the metabolism of xenobiotics in the body. In humans, the CYP1A2 enzyme is encoded by the CYP1A2gene.
CYP1A2 is a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. CYP1A2 localizes to the endoplasmic reticulum and its expression is induced by some polycyclic aromatic hydrocarbons (PAHs), some of which are found in cigarette smoke. The enzyme's endogenous substrate is unknown; however, it is able to metabolize some PAHs to carcinogenic intermediates. Other xenobiotic substrates for this enzyme include caffeine, aflatoxin B1, and acetaminophen. The transcript from this gene contains four Alu sequences flanked by direct repeats in the 3' untranslated region.
Expression of CYP1A2 appears to be induced by various dietary constituents. Vegetables such as cabbages, cauliflower and broccoli are known to increase levels of CYP1A2. Lower activity of CYP1A2 in South Asians appears to be due to cooking these vegetables in curries using ingredients such as cumin and turmeric, ingredients known to inhibit the enzyme.
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