The murine double minute 2 (mdm2) gene encodes a negative regulator of the p53 tumor suppressor. Amplification of mdm2 or increased expression by unknown mechanisms occurs in many tumors. Thus, increased levels of MDM2 would inactivate the apoptotic and cell cycle arrest functions of p53, as do deletion or mutation of p53, common events in the genesis of many kinds of tumors. MDM2 functions as an E3 ubiquitin ligase to degrade p53. MDM2 also binds another tumor suppressor, ARF. This interaction sequesters MDM2 in the nucleolus away from p53, thus activating p53. Many additional MDM2 interacting proteins have been identified. Functions of MDM2 independent of p53 have also been identified. This article is an introduction to MDM2, its structure and biological functions, as well as its relationship to its binding partners.

中文翻译：

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MDM2，简介。

鼠双分2（mdm2）基因编码p53肿瘤抑制因子的负调控因子。mdm2的扩增或通过未知机制增加的表达发生在许多肿瘤中。因此，增加水平的MDM2将使p53的凋亡和细胞周期阻滞功能失活，而p53的缺失或突变也将失活，这是多种肿瘤发生中的常见事件。MDM2充当E3泛素连接酶以降解p53。MDM2还与另一种肿瘤抑制因子ARF结合。这种相互作用使核仁中的MDM2远离p53，从而激活p53。已经鉴定出许多其他的MDM2相互作用蛋白。还确定了独立于p53的MDM2功能。本文是对MDM2，其结构和生物学功能及其与结合伴侣的关系的介绍。