DNA binding is required for the apoptogenic action of apoptosis inducing factor
DNA binding is required for the apoptogenic action of apoptosis inducing factor
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DOI：
10.1038/nsb836
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发表时间：
2002-09-01
期刊：
影响因子：
--
通讯作者：
Wu, H
中科院分区：
文献类型：
--
作者：
Ye, H;Cande, C;Wu, H
细胞凋亡或程序性细胞死亡的执行包括半胱天冬酶依赖性和半胱天冬酶非依赖性过程。凋亡诱导因子（AIF）被认为是半胱天冬酶非依赖性细胞死亡的主要参与者。它通过未知的分子机制诱导染色质凝聚和初始DNA切割。在这里，我们报告了1.8埃分辨率的人类AIF的晶体结构。该结构揭示了在AIF表面存在强的正静电势，尽管整个蛋白质的计算等电点是中性的。我们表明，重组AIF与DNA相互作用的序列独立的方式。此外，在用凋亡刺激物处理的细胞中，内源性AIF在核形态变化的早期阶段与DNA共定位。基于结构的诱变表明，DNA结合缺陷的AIF突变体不能诱导细胞死亡，同时保留核转位。从诱变鉴定的潜在DNA结合位点也与DNA双链体的计算对接相一致。这些观察结果表明，AIF诱导的细胞核凋亡需要与DNA的直接相互作用。
The execution of apoptosis or programmed cell death comprises both caspase-dependent and caspase-independent processes. Apoptosis inducing factor (AIF) was identified as a major player in caspase-independent cell death. It induces chromatin condensation and initial DNA cleavage via an unknown molecular mechanism. Here we report the crystal structure of human AIF at 1.8 Angstrom resolution. The structure reveals the presence of a strong positive electrostatic potential at the AIF surface, although the calculated isoelectric point for the entire protein is neutral. We show that recombinant AIF interacts with DNA in a sequence-independent manner. In addition, in cells treated with an apoptotic stimulus, endogenous AIF becomes co-localized with DNA at an early stage of nuclear morphological changes. Structure-based mutagenesis shows that DNA-binding defective mutants of AIF fail to induce cell death while retaining nuclear translocation. The potential DNA-binding site identified from mutagenesis also coincides with computational docking of a DNA duplex. These observations suggest that AIF-induced nuclear apoptosis requires a direct interaction with DNA.