Characterization of the Drosophila caspase, DAMM
Characterization of the Drosophila caspase, DAMM
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DOI：
10.1074/jbc.m009444200
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发表时间：
2001-07-06
影响因子：
4.8
通讯作者：
Kumar, S
中科院分区：
文献类型：
--
作者：
Harvey, NL;Daish, T;Kumar, S
Caspase酶是后生动物细胞凋亡的主要效应因子，基因组分析表明果蝇中有7种Caspase酶，其中6种已被鉴定。在这里，我们描述了最后的果蝇caspase，DAMM的克隆和表征。与哺乳动物效应子半胱天冬酶相似，DAMM缺乏一个长的前结构域。我们发现DAMM前体，沿着半胱天冬酶DRONC和DECAY，在经历凋亡的细胞中被部分加工。低水平的damm mRNA在果蝇胚胎发育的早期阶段普遍表达。在幼虫唾液腺和中肠以及成虫卵室中检测到相对高水平的damm mRNA。DAMM在培养细胞中的异位表达诱导细胞凋亡，同样，转基因DAMM的过度表达，但不是一个催化失活的DAMM突变体，在果蝇中的结果在粗糙的眼睛表型。我们证明，催化失活的DAMM突变体蛋白的表达显着抑制粗糙的眼睛表型由于过度表达HID，这表明DAMM可能需要在HID介导的细胞死亡途径。
Caspases are main effecters of apoptosis in metazoans, Genome analysis indicates that there are seven caspases in Drosophila, six of which have been previously characterized. Here we describe the cloning and characterization of the last Drosophila caspase, DAMM. Similar to mammalian effector caspases, DAMM lacks a long prodomain, We show that the DAMM precursor, along with the caspases DRONC and DECAY, is partially processed in cells undergoing apoptosis, Recombinant DAMM produced in Escherichia coli shows significant catalytic activity on a pentapeptide caspase substrate. Low levels of damm mRNA are ubiquitously expressed in Drosophila embryos during early stages of development. Relatively high levels of damm mRNA are detected in larval salivary glands and midgut, and in adult egg chambers. Ectopic expression of DAMM in cultured cells induces apoptosis, and similarly, transgenic overexpression of DAMM, but not of a catalytically inactive DAMM mutant, in Drosophila results in a rough eye phenotype, We demonstrate that expression of the catalytically inactive DAMM mutant protein significantly suppresses the rough eye phenotype due to the overexpression of HID, suggesting that DAMM may be required in a hid-mediated cell death pathway.