TRANSCRIPTIONAL REGULATION OF CYTOCHROME P-450 GENES

大多数P-450基因在转录水平上受到调控。 水平。在发育的不同阶段，P-450基因成为 转录激活。我们正在研究其中的几个P- 在发育过程中被激活的450个基因。这些基因有 被克隆并完全测序及其启动子区域 已经被确认了。正在检测的基因是IIAI、IIA2、 IIC7和IIEI。IIAI和IIEI被转录激活 无论是男性还是女性，出生后都会立即死亡。然而，IIAI， 在青春期的男性身上会受到特别的抑制。IIA2变成了 男性在青春期时被激活，从来没有表达过 在雌性身上。IIC7在男性和女性中都处于激活状态 青春期。研究顺式和反式作用元件 对于这些基因的激活，我们使用了一种无细胞的体外 源自大鼠肝脏的转录系统。启动子区域 上面的每个基因都在细胞中被忠实地转录- 自由系统。目前正在努力确定DNA序列的特征 负责激活的元素和蛋白质因子 这些基因的转录。

The majority of P-450 genes are regulated at the transcriptional level. During distinct stages of development, P-450 genes became transcriptionally activated. We are studying several of these P- 450 genes that are activated during development. The genes have been cloned and completely sequenced and their promoter regions have been identified. The genes being examined are IIAI, IIA2, IIC7, and IIEI. IIAI and IIEI became transcriptionally activated immediately after birth in both males and females. IIAI, however, becomes specifically suppressed in males at puberty. IIA2 becomes activated in males when they reach puberty and is never expressed in females. IIC7 is activated in both males and females at puberty. To study the cis- and trans-acting elements responsible for these gene activations, we are using a cell-free in vitro transcription system derived from rat liver. Promotor regions of each of the above genes were faithfully transcribed in the cell- free system. Efforts are under way to characterize DNA sequence elements and protein factors responsible for activating transcription of these genes.