The yeast Pif1p DNA helicase preferentially unwinds RNA DNA substrates.
The yeast Pif1p DNA helicase preferentially unwinds RNA DNA substrates.
复制标题
酵母PIF1P DNA解旋酶优先放出RNA DNA底物。
DOI：
10.1093/nar/gkm613
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发表时间：
2007
影响因子：
14.9
通讯作者：
Zakian, Virginia A.
中科院分区：
文献类型：
--
作者：
Boule, Jean-Baptiste;Zakian, Virginia A.
Pif 1 p是DNA解旋酶的PIF 1家族的原型成员，该家族是从酵母到人类保守的SFI解旋酶的亚家族。面包酵母Pif 1 p参与线粒体、核糖体和端粒DNA的维持，也可能通过影响冈崎片段成熟在染色体复制中发挥一般作用。在这里，我们调查Pif 1 p的底物偏好。该酶优先在RNA-DNA杂交体上具有活性，如通过与DNA-DNA杂交体相比RNA-DNA杂交体上更快的解旋速率所看到的。当使用叉状底物时，Pif 1 p表现出对RNA-DNA杂交体的偏好。这种优先解旋不能与优先结合的Pif 1 p的底物是最容易解旋。虽然单链DNA结合蛋白复制蛋白A（RPA）的加入刺激了所有底物上的解旋酶反应，但它并没有减少Pif 1 p对RNA-DNA底物的偏好。因此，分叉的RNA-DNA底物是Pif 1 p在体外的有利底物。我们讨论这些发现的酶的已知生物学作用。
Pif1p is the prototypical member of the PIF1 family of DNA helicases, a subfamily of SFI helicases conserved from yeast to humans. Baker's yeast Pif1p is involved in the maintenance of mitochondrial, ribosomal and telomeric DNA and may also have a general role in chromosomal replication by affecting Okazaki fragment maturation. Here we investigate the substrate preferences for Pif1p. The enzyme was preferentially active on RNA–DNA hybrids, as seen by faster unwinding rates on RNA–DNA hybrids compared to DNA–DNA hybrids. When using forked substrates, which have been shown previously to stimulate the enzyme, Pif1p demonstrated a preference for RNA–DNA hybrids. This preferential unwinding could not be correlated to preferential binding of Pif1p to the substrates that were the most readily unwound. Although the addition of the single-strand DNA-binding protein replication protein A (RPA) stimulated the helicase reaction on all substrates, it did not diminish the preference of Pif1p for RNA–DNA substrates. Thus, forked RNA–DNA substrates are the favored substrates for Pif1p in vitro. We discuss these findings in terms of the known biological roles of the enzyme.
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影响因子：
4.8
作者：
Doherty, KM;Sommers, JA;Brosh, RM
通讯作者：
Brosh, RM
影响因子：
64.8
作者：
Boulé, JB;Vega, LR;Zakian, VA
通讯作者：
Zakian, VA
DOI：
10.1073/pnas.80.17.5345
发表时间：
1983-01-01
期刊：
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA-BIOLOGICAL SCIENCES
影响因子：
--
作者：
FOURY, F;KOLODYNSKI, J
通讯作者：
KOLODYNSKI, J
PIF1样解旋酶在维持基因组稳定性中的作用。
影响因子：
14.9
作者：
Boulé JB;Zakian VA
通讯作者：
Zakian VA
影响因子：
4.8
作者：
Brosh, RM;Orren, DK;Bohr, VA
通讯作者：
Bohr, VA