Abstract
Abstract: :
Purpose:To establish a comparative expression profile of the mouse cytochrome P450 gene family and analyze the temporal relationships in the expression of the CYP1 genes. Methods: Expression profiles were developed by PCR based screening of Mouse I panel (Clontech) containing normalized cDNA samples from four embryonic stages (G.D. 7, 11, 15 and 17) and eight adult tissues: heart, brain, spleen, lung, liver, skeletal muscle, kidney and testis. The individual gene-specific PCR assays were uniform with respect to the primer Tm, amplicon size, reaction conditions and the number of cycles used. Densitometry analysis was performed with Scion Image software program. The level of expression of each gene was translated into ng of RT-PCR product. Results: Expression profiles for 40 genes representing all known cytochrome P450 families in mouse were developed. Cytochrome P450s were detected in the gastrulation phase. Number of expressed genes steadily increases during somitogenesis and organogenesis phase of development. In adult tissues, the largest number of P450s were detected in the liver (31) followed by kidney (30), testis (26) and lung (24). Heart had the fewest number (13). Of special interest was the expression profile of P450 genes belonging to sub-family Cyp1 because the mutant forms of the human ortholog of Cyp1b1 cause primary congenital glaucoma. Cyp1a1 and Cyp1b1 demonstrated a complex non-overlapping pattern of expression during embryonic development. Cyp1a1 was detected only at embryonic day 7 while Cyp1b1 was detected on days 11, 15 and 17. In adult tissues, the highest Cyp1a1 expression was in the lung and liver. Cyp1b1 was not detected in the liver but was present in all other tissues. Cyp1a2 was detected only in the adult liver. Conclusions: Our data indicates that Cyp1a1 and Cyp1a2 can not compensate for Cyp1b1 deficiency during embryonic development since the latter is absent and the former appears at different temporal points in development. Supported by AHAF National Glaucoma Research grant to I.S. and NIH (EY-11095) to M.S.
Keywords: gene/expression • molecular biology