Research on the role of a new hormone-inducible transcription factor GIOT for the ovarian function.

本研究采用减法克隆的方法，在大鼠卵巢中克隆并鉴定了PMSG快速诱导的新型含锌指基因。结构分析表明，它们是C2H2锌指类转录因子的成员。锌指重复序列首先在爪蟾转录因子TFIIIA中被发现，随后在大量真核生物调控蛋白中被发现。因此我们将其命名为促性腺激素诱导转录因子（GIOTs）。GIOTs由两个密切相关的基因组成，分别被命名为GIOT-1和GIOT-2。GIOT-1仅在类固醇组织和垂体中表达，而GIOT-2在大鼠组织中广泛分布。GIOT-1受大鼠卵巢促性腺激素的强烈诱导，可以抑制具有异源启动子结构的基因的转录。因此，GIOT实际上在卵巢中具有抑制基因表达的活性。

In this study, by using the subtraction cloning method, we have cloned and characterized novel zinc-finger containing genes, that were rapidly induced by PMSG in the rat ovary. Structural analysis of the genes revealed that they are members of C2H2 zinc-finger class of transcription factors. The zinc-finger repeat is first found in Xenopus transcription factor TFIIIA and subsequently found in a large number of eukaryotic regulatory proteins. Therefore we named them Gonadotropin Inducible Transcription Factors (GIOTs). GIOTs constitute a gene family of two closely related genes, which are designated GIOT-1 and GIOT-2. GIOT-1 is expressed solely in steroidogenic tissues and pituitary, whereas GIOT-2 distributes widely in rat tissues. GIOT-1 is strongly induced by gonadotropins in the rat ovary and can suppress transcription of genes having a heterologous promoter construct. Therefore GIOT is actually active in the ovary to suppress gene expression.