甾体激素受体超家族的基因调控机制

Mechanism of Gene Expression Regulated by Steroid Hormone Receptor Superfamily.

甾体激素受体超家族是一类基因反式作用因子，对ＲＮＡ聚合酶Ⅱ转录的某些蛋白质基因和ＲＮＡ聚合酶Ⅰ转录的核糖体ＲＮＡ基因均有正或负的转录调节作用．超家族对ＲＮＡｐｏｌⅡ转录的基因调控的机理包括受体激活，相关蛋白解离，磷酸化，同源／异源二聚化，核转位，与正／负激素应答元件及相应转录蛋白作用，最终激活或抑制特异靶基因的转录．甾体激素对ＲＮＡｐｏｌⅠ转录的基因的调节作用以及超家族中的经典受体和孤儿受体非配合的激活机制是目前研究的热点．

Steroid hormone receptor super-family is a kind of gene trans-acting factorsand modulates both RNA pol -directedrRNA transcription and RNA pol Ⅱ-directedtranscription. The melocular pathway of RNApol Ⅱ-directed transcription regulated by thesuperfamily includes the binding of ligand,dissociation of relative proteins,receptorphosphorylation,homo/hetero-dimerization,nuclear localization and interaction with posi-tive or negative hormone response elementsand related transcriptional proteins. As a re-sult,the specific target gene is activated or re-pressed.Now more studies focus on the acti-vating mechanism of some classic receptorsand orphan receptors with or without ligand,as well as their regulations on specific genetranscription.