echinus, required for interommatidial cell sorting and cell death in the Drosophila pupal retina, encodes a protein with homology to ubiquitin-specific proteases.
echinus, required for interommatidial cell sorting and cell death in the Drosophila pupal retina, encodes a protein with homology to ubiquitin-specific proteases.
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DOI：
10.1186/1471-213x-7-82
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发表时间：
2007-07-05
影响因子：
--
通讯作者：
Hay BA
中科院分区：
文献类型：
--
作者：
Copeland JM;Bosdet I;Freeman JD;Guo M;Gorski SM;Hay BA
细胞程序性死亡是用来清除果蝇幼虫视网膜小眼之间的多余细胞。这种死亡是建立结晶性的六角形小眼填充所必需的，这是成年苍蝇眼的特征。在先前描述的棘球绦虫突变体中，细胞死亡之前的细胞间细胞分离发生得相对正常。球间细胞死亡被部分抑制，导致成人眼含有过多的色素细胞，并且小眼轻度紊乱。这些结果表明，棘球蛋白在幼虫视网膜中的作用主要是促进室间细胞死亡。我们产生了一些新的棘球绦虫等位基因，其中一些可能是零突变。对这些等位基因的分析为棘球蛋白在细胞分选和细胞死亡中发挥作用提供了证据。棘球绦虫编码一种与泛素特异性蛋白酶同源的蛋白质。这些蛋白质在泛素C末端裂解泛素结合蛋白。棘球蛋白基因座编码多种剪接形式，包括两种缺乏残基的蛋白质，这些残基被认为是脱泛素化活性的关键。令人惊讶的是，在缺乏泛素特异性蛋白酶活性关键残基的版本以及预测具有功能的版本中，眼睛中普遍存在的表达挽救了棘球绦虫功能丧失的表型。最后，没有检测到棘球蛋白的丧失和功能获得与一些已知的凋亡调节因子之间的遗传交互作用。这些基因包括Notch、EGFR、caspase Dronc、Drice、DCP-1、Dream、caspase激活剂、RPR、HID和GRIM、caspase抑制因子DIAP1和Lozenger或Klumpfuss。棘球蛋白基因座编码一种蛋白质的多种剪接形式，与泛素特定的蛋白酶同源，但至少在棘球蛋白过度表达时，蛋白水解酶活性不太可能是棘球蛋白功能所必需的。对可能的棘球绦虫零等位基因和遗传交互作用的描述表明，棘球棘球绦虫在一个新的点(S)调节苍蝇眼的胞间细胞分类和/或细胞死亡。
Programmed cell death is used to remove excess cells between ommatidia in the Drosophila pupal retina. This death is required to establish the crystalline, hexagonal packing of ommatidia that characterizes the adult fly eye. In previously described echinus mutants, interommatidial cell sorting, which precedes cell death, occurred relatively normally. Interommatidial cell death was partially suppressed, resulting in adult eyes that contained excess pigment cells, and in which ommatidia were mildly disordered. These results have suggested that echinus functions in the pupal retina primarily to promote interommatidial cell death. We generated a number of new echinus alleles, some likely null mutants. Analysis of these alleles provides evidence that echinus has roles in cell sorting as well as cell death. echinus encodes a protein with homology to ubiquitin-specific proteases. These proteins cleave ubiquitin-conjugated proteins at the ubiquitin C-terminus. The echinus locus encodes multiple splice forms, including two proteins that lack residues thought to be critical for deubiquitination activity. Surprisingly, ubiquitous expression in the eye of versions of Echinus that lack residues critical for ubiquitin specific protease activity, as well as a version predicted to be functional, rescue the echinus loss-of-function phenotype. Finally, genetic interactions were not detected between echinus loss and gain-of-function and a number of known apoptotic regulators. These include Notch, EGFR, the caspases Dronc, Drice, Dcp-1, Dream, the caspase activators, Rpr, Hid, and Grim, the caspase inhibitor DIAP1, and Lozenge or Klumpfuss. The echinus locus encodes multiple splice forms of a protein with homology to ubiquitin-specific proteases, but protease activity is unlikely to be required for echinus function, at least when echinus is overexpressed. Characterization of likely echinus null alleles and genetic interactions suggests that echinus acts at a novel point(s) to regulate interommatidial cell sorting and/or cell death in the fly eye.