Halloween genes encode P450 enzymes that mediate steroid hormone biosynthesis in Drosophila melanogaster
Halloween genes encode P450 enzymes that mediate steroid hormone biosynthesis in Drosophila melanogaster
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DOI：
10.1016/j.mce.2003.11.003
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发表时间：
2004-02-27
影响因子：
4.1
通讯作者：
Gilbert, LI
中科院分区：
文献类型：
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作者：
Gilbert, LI
万圣节基因家族成员的突变导致胚胎死亡。我们已经证明，这些基因中的两个编码负责蜕皮激素合成中特定步骤的酶，蜕皮激素是一种多羟基甾醇，是所有节肢动物主要蜕皮激素20-羟基蜕皮激素的前体。这两种线粒体P450酶，由非实体（dib）（CYP 302 A1）和阴影（sad）（CYP 315 A1）编码，分别是C22和C2羟化酶，如通过将基因转染到S2细胞中和随后的生化分析所示。这是蜕皮激素生物合成途径中的最后两种酶。第三种酶是蜕皮激素转化为20-羟基蜕皮激素所必需的，即20-单加氧酶，由shade（shd）（CYP 314 A1）编码。所有三种酶都是线粒体的，尽管阴影具有暗示线粒体和微粒体位置的基序。通过标记这些酶，它们的亚细胞位置已被共聚焦显微镜证实。正如预期的那样，阴影存在于多个组织中，而脱离实体和阴影仅限于环腺。所使用的范例应使我们能够定义酶介导的整个蜕皮甾类生物合成途径。(C)2003爱思唯尔爱尔兰有限公司保留所有权利。
Mutation of members of the Halloween gene family results in embryonic lethality. We have shown that two of these genes code for enzymes responsible for specific steps in the synthesis of ecdysone, a polyhydroxylated sterol that is the precursor of the major molting hormone of all arthropods, 20-hydroxyecdysone. These two mitochondrial P450 enzymes, coded for by disembodied (dib) (CYP302A1) and shadow (sad) (CYP315A1), are the C22 and C2 hydroxylases, respectively, as shown by transfection of the gene into S2 cells and subsequent biochemical analysis. These are the last two enzymes in the ecdysone biosynthetic pathway. A third enzyme, necessary for the critical conversion of ecdysone to 20-hydroxyecdysone, the 20-monooxygenase, is encoded by shade (shd) (CYP314A1). All three enzymes are mitochondrial although shade has motifs suggesting both mitochondrial and microsomal locations. By tagging these enzymes, their subcellular location has been confirmed by confocal microscopy. Shade is present in several tissues as expected while disembodied and shadow are restricted to the ring gland. The paradigm used should allow us to define the enzymes mediating the entire ecdysteroid biosynthetic pathway. (C) 2003 Elsevier Ireland Ltd. All rights reserved.