Crystal Structures of Human SIRT3 Displaying Substrate-induced Conformational Changes
Crystal Structures of Human SIRT3 Displaying Substrate-induced Conformational Changes
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DOI：
10.1074/jbc.m109.014928
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发表时间：
2009-09-04
影响因子：
4.8
通讯作者：
Perni, Robert B.
中科院分区：
文献类型：
--
作者：
Jin, Lei;Wei, Wentao;Perni, Robert B.
SIRT3是一种主要的线粒体NAD（+）依赖蛋白去乙酰化酶，在调节线粒体代谢和能量产生中起重要作用，并与运动和热量限制的有益作用有关。SIRT3正在成为治疗代谢和神经疾病的潜在治疗靶点。我们报道了人类SIRT3的第一组晶体结构，一个无底物的载脂蛋白结构，一个含有天然底物乙酰辅酶a合成酶2的乙酰赖氨酸的肽的结构，一个被硫乙酰基肽捕获的反应中间结构，以及一个与去硫乙酰化肽结合的结构。这些结构提供了对反应所需的两种底物，乙酰化底物肽和nad（+）引起的构象变化的见解。此外，等温滴定量热法的结合研究表明，乙酰化肽是第一个与SIRT3结合的底物，在NAD（+）之前。这些结构和生物物理研究为了解SIRT3去乙酰化活性的结构和功能关系提供了关键的见解。
SIRT3 is a major mitochondrial NAD(+)-dependent protein deacetylase playing important roles in regulating mitochondrial metabolism and energy production and has been linked to the beneficial effects of exercise and caloric restriction. SIRT3 is emerging as a potential therapeutic target to treat metabolic and neurological diseases. We report the first sets of crystal structures of human SIRT3, an apo-structure with no substrate, a structure with a peptide containing acetyl lysine of its natural substrate acetyl-CoA synthetase 2, a reaction intermediate structure trapped by a thioacetyl peptide, and a structure with the dethioacetylated peptide bound. These structures provide insights into the conformational changes induced by the two substrates required for the reaction, the acetylated substrate peptide andNAD(+). In addition, the binding study by isothermal titration calorimetry suggests that the acetylated peptide is the first substrate to bind to SIRT3, before NAD(+). These structures and biophysical studies provide key insight into the structural and functional relationship of the SIRT3 deacetylation activity.