Excision of the Drosophila mariner transposon Mos1:: Comparison with bacterial transposition and V(D)J recombination
Excision of the Drosophila mariner transposon Mos1:: Comparison with bacterial transposition and V(D)J recombination
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DOI：
10.1016/s1097-2765(02)00798-0
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发表时间：
2003-01-01
期刊：
影响因子：
16
通讯作者：
Finnegan, DJ
中科院分区：
文献类型：
--
作者：
Dawson, A;Finnegan, DJ
有人提出，现代免疫系统是从古代脊椎动物的转座子进化而来的。虽然人们对细菌转座因子催化双链末端断裂的机制了解甚多，但对真核生物转座因子如何进行这些反应知之甚少。我们研究了真核转座因子mariner进行DNA切割的机制。我们发现非转移链首先被切割，不像原核转座子首先切割转移链。第一链切割与第二链切割不紧密耦合，可以独立于突触发生，如在V(D)J重组中发生，而不是在原核转座子的转座中发生。然而，与V(D)J重组不同，mariner的第二链切割不是通过发夹中间体发生的。
It has been proposed that the modern immune system has evolved from a transposon in an ancient vertebrate. While much is known about the mechanism by which bacterial transposable elements catalyze double-strand breaks at their ends, less is known about how eukaryotic transposable elements carry out these reactions. We have examined the mechanism by which mariner, a eukaryotic transposable element, performs DNA cleavage. We show that the nontransferred strand is cleaved initially, unlike prokaryotic transposons which cleave the transferred strand first. First strand cleavage is not tightly coupled to second strand cleavage and can occur independently of synapsis, as happens in V(D)J recombination but not in transposition of prokaryotic transposons. Unlike V(D)J recombination, however, second strand cleavage of mariner does not occur via a hairpin intermediate.