中文摘要：

Sir2（silence information regulator）基因家族是一种保守的从古细菌到哺乳动物都存在的NAD^＋依赖的组蛋白／非组蛋白去乙酰化酶。在酵母中，Sir2连同与它相互作用的几个蛋白质在基因沉默、基因组稳定性、细胞寿命以及代谢调节上起着不可缺少的作用。其主要的作用机制是：热量限制降低了抑制物烟酰胺的浓度，从而激活了Sir2的组蛋白去乙酰化功能。在哺乳动物中，有7个Sir2同源基因，分别命名为SIRT1到SIRT7。其中SIRT1研究的最多，它在DNA损伤修复、细胞周期控制、抑制细胞凋亡、抵抗氧化逆境和延长细胞寿命方面起着重要作用。它的这些功能是通过和p53、FOX03、Ku70和PGC-1α等蛋白质之间的相互作用而实现的。

英文摘要：

The Sir2 （silence information regulator） gene family is an NAD^＋ dependent protein deacetylase which is conserved from archaebacteria to humans. In yeast, it has been implicated to play roles in gene silencing, genome stability, longevity and metabolism through histone deacetylase activity during calorie restriction. Mammals have seven homologies of Sir2, namely SIRT1 to SIRTT. The SIRT1 gene has been proven to play a pivotal role in the regulation of DNA repair, metabolism, apoptosis and extend life span. This function is achieved via the interaction between SIRT1 and p53, FOXO3, Ku70 and PGC-1α .