Molecular architecture of a eukaryotic DNA transposase
Molecular architecture of a eukaryotic DNA transposase
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DOI：
10.1038/nsmb970
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发表时间：
2005-08-01
影响因子：
16.8
通讯作者：
Dyda, F
中科院分区：
文献类型：
--
作者：
Hickman, AB;Perez, ZN;Dyda, F
移动的元件和它们的非活性残余物在大多数真核生物基因组中占很大比例，它们在基因组进化中起着核心作用。50多年前，McClintock报道了玉米中一种胁迫诱导的基因组不稳定性，其中离散的DNA片段在染色体位置之间移动。我们目前对酶催化转座的机理理解主要限于原核转座酶。来自家蝇的爱马仕转座子是真核hAT超家族的一部分，该超家族包括来自果蝇的流浪汉、麦克林托克的玉米激活剂和来自金鱼草的Tam3。我们在这里报告的三维结构的功能活性形式的转座酶从爱马仕在2.1埃的分辨率。爱马仕蛋白具有原核转座酶的一些结构特征，包括具有逆转录病毒整合酶折叠的结构域。然而，该结构域通过插入另外的结构域而被破坏。最后，只有当爱马仕组装成六聚体时才能观察到转座。
Mobile elements and their inactive remnants account for large proportions of most eukaryotic genomes, where they have had central roles in genome evolution. Over 50 years ago, McClintock reported a form of stress-induced genome instability in maize in which discrete DNA segments move between chromosomal locations. Our current mechanistic understanding of enzymes catalyzing transposition is largely limited to prokaryotic transposases. The Hermes transposon from the housefly is part of the eukaryotic hAT superfamily that includes hobo from Drosophila, McClintock's maize Activator and Tam3 from snapdragon. We report here the three-dimensional structure of a functionally active form of the transposase from Hermes at 2.1-angstrom resolution. The Hermes protein has some structural features of prokaryotic transposases, including a domain with a retroviral integrase fold. However, this domain is disrupted by the insertion of an additional domain. Finally, transposition is observed only when Hermes assembles into a hexamer.