Scientific background: |
CYP7A1 (Cytochrome P450 Subfamily VIIA Polypeptide 1), also called CYP7 or CHOLESTEROL 7-ALPHA-HYDROXYLASE, is an enzyme that in humans is encoded by the CYP7A1 gene. Using both mouse-human somatic cell hybrids and in situ chromosomal hybridization, Cohen et al. (1992) mapped the CYP7 gene to 8q11-q12. By transfection of reporter constructs, mutation analysis, and DNase footprinting, Molowa et al. (1992) identified areas of the CYP7A1 promoter region that showed hepatocyte-specific activation. They found HNF3 to be an activator of CYP7A1 activity. Agellon et al. (2002) found that wildtype mice and mice transgenic for human CYP7A1 respond differently to cholesterol feeding. Cholesterol feeding stimulated Cyp7a1 mRNA abundance and enzymatic activity in wildtype mice, but repressed human CYP7A1 mRNA and activity in transgenic mice. |
References: |
1. Agellon, L. B., Drover, V. A. B., Cheema, S. K., Gbaguidi, G. F., Walsh, A. Dietary cholesterol fails to stimulate the human cholesterol 7-alpha-hydroxylase gene (CYP7A1) in transgenic mice. J. Biol. Chem. 277: 20131-20134, 2002.
2. Cohen, J. C., Cali, J. J., Jelinek, D. F., Mehrabian, M., Sparkes, R. S., Lusis, A. J., Russell, D. W., Hobbs, H. H. Cloning of the human cholesterol 7-alpha-hydroxylase gene (CYP7) and localization to chromosome 8q11-q12. Genomics 14: 153-161, 1992.
3. Molowa, D. T., Chen, W. S., Cimis, G. M., Tan, C. P. Transcriptional regulation of the human cholesterol 7 alpha-hydroxylase gene. Biochemistry 31: 2539-2544, 1992.
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