Department of Cell Biology, University of Texas Southwestern Medical Center at Dallas, USA.
Cell Death Differ. 2012 Oct;19(10):1655-63. doi: 10.1038/cdd.2012.47. Epub 2012 Apr 27.
Heavy alcohol consumption provokes an array of degenerative pathologies but the signals that couple alcohol exposure to regulated forms of cell death are poorly understood. Using Drosophila as a model, we genetically establish that the severity of ethanol challenge dictates the type of death that occurs. In contrast to responses seen under acute exposure, cytotoxic responses to milder challenges required gene encoding components of the apoptosome, Dronc and Dark. We conducted a genome-wide RNAi screen to capture targets that specifically mediate ethanol-induced cell death. One effector, Drat, encodes a novel protein that contains an ADH domain but lacks essential residues in the catalytic site. In cultured cells and neurons in vivo, depletion of Drat conferred protection from alcohol-induced apoptosis. Adults mutated for Drat showed both improved survival and enhanced propensities toward sedation after alcohol challenge. Together, these findings highlight novel effectors that support regulated cell death incited by alcohol stress in vitro and in vivo.
大量饮酒会引发一系列退行性病变,但将酒精暴露与受调控的细胞死亡形式联系起来的信号机制还知之甚少。我们利用果蝇作为模型,从遗传学角度证实了乙醇刺激的严重程度决定了发生的死亡类型。与急性暴露时观察到的反应相反,对轻度刺激的细胞毒性反应需要编码凋亡体、Dronc 和 Dark 的基因成分。我们进行了全基因组 RNAi 筛选,以捕获专门介导乙醇诱导细胞死亡的靶标。其中一个效应物 Drat 编码一种新型蛋白,该蛋白含有 ADH 结构域,但催化位点缺少必需残基。在培养的细胞和体内神经元中,耗尽 Drat 可防止酒精诱导的细胞凋亡。突变 Drat 的成虫在酒精刺激后不仅存活率提高,而且镇静倾向增强。这些发现共同强调了新型效应物在体外和体内支持由酒精应激引发的受调控细胞死亡。