Complementation between HIV integrase proteins mutated in different domains.
Complementation between HIV integrase proteins mutated in different domains.
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不同域中突变的 HIV 整合酶蛋白之间的互补。
DOI：
10.1002/j.1460-2075.1993.tb05995.x
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Ronald H. A. Plasterk
中科院分区：
文献类型：
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作者：
D. V. Gent;Cornelis Vink;A. A. M. O. Groeneger;Ronald H. A. Plasterk
人类免疫缺陷病毒（HIV）整合酶（IN）从病毒DNA的3′端切割下两个核苷酸，并将病毒DNA整合到目标DNA中。此前，已在HIV整合酶蛋白中鉴定出三个功能结构域：（i）中央催化结构域，（ii）C - 末端DNA结合结构域，以及（iii）N - 末端区域，该区域对活性也是必需的。我们现在已经研究了在不同结构域发生突变的整合酶蛋白是否能够相互补充。突变体D116I不含有完整的活性位点，但能结合DNA，而C - 末端缺失突变体CΔ73不结合DNA，但具有完整的活性位点。这两种突变蛋白都不能介导位点特异性切割或整合。然而，两种蛋白的混合物具有活性，这表明整合酶作为一个寡聚体发挥作用，并且两个亚基可以具有不同的功能；一个亚基结合（病毒）DNA，另一个亚基提供活性位点。我们发现了三类突变体，与上述三个结构域相对应。来自不同类别的突变体（而非来自同一类别）能够相互补充。然而，当N - 末端和C - 末端存在于同一分子上时，互补作用最为有效。
HIV integrase (IN) cleaves two nucleotides off the 3′ end of viral DNA and integrates viral DNA into target DNA. Previously, three functional domains in the HIV IN protein have been identified: (i) the central catalytic domain, (ii) the C‐terminal DNA binding domain, and (iii) the N‐terminal region, which is also necessary for activity. We have now investigated whether IN proteins mutated in different domains can complement each other. Mutant D116I does not contain an intact active site, but does bind DNA, whereas the C‐terminal deletion mutant C delta 73 does not bind DNA, but does have an intact active site. Neither mutant protein mediates site‐specific cleavage or integration. However, a mixture of both proteins is active, suggesting that IN functions as an oligomer, and that two subunits can have different functions; one subunit binds the (viral) DNA and another subunit provides the active site. We found three classes of mutants, corresponding to the three domains mentioned above. Mutants from different classes, but not from the same class, can complement each other. However, complementation is most efficient when the N‐ and C‐termini are present on the same molecule.