Koehn Demelza R, Haring Stuart J, Williams Jaime M, Malone Robert E
Department of Biology, University of Iowa, Iowa City, Iowa 52242-1324.
Genetics. 2009 Jun;182(2):447-58. doi: 10.1534/genetics.109.102640. Epub 2009 Mar 30.
Meiotic recombination in Saccharomyces cerevisiae is initiated by the creation of DNA double strand breaks (DSBs), an event requiring 10 recombination initiation proteins. Published data indicate that these 10 proteins form three main interaction subgroups [(Spo11-Rec102-Rec104-Ski8), (Rec114-Rec107-Mei4), and (Mre11-Rad50-Xrs2)], but certain components from each subgroup may also interact. Although several of the protein-protein interactions have been defined, the mechanism for DSB formation has been challenging to define. Using a variation of the approach pioneered by others, we have tethered 8 of the 10 initiation proteins to a recombination coldspot and discovered that in addition to Spo11, 6 others (Rec102, Rec104, Ski8, Rec114, Rec107, and Mei4) promote DSB formation at the coldspot, albeit with different frequencies. Of the 8 proteins tested, only Mre11 was unable to cause DSBs even though it binds to UAS(GAL) at GAL2. Our results suggest there may be several ways that the recombination initiation proteins can associate to form a functional initiation complex that can create DSBs.
酿酒酵母中的减数分裂重组是由DNA双链断裂（DSB）的产生引发的，这一事件需要10种重组起始蛋白。已发表的数据表明，这10种蛋白形成了三个主要的相互作用亚组[（Spo11-Rec102-Rec104-Ski8）、（Rec114-Rec107-Mei4）和（Mre11-Rad50-Xrs2）]，但每个亚组中的某些成分也可能相互作用。尽管已经确定了几种蛋白质-蛋白质相互作用，但DSB形成的机制一直难以确定。我们采用了其他人开创的方法的一种变体，将10种起始蛋白中的8种与一个重组冷点相连，发现除了Spo11之外，其他6种蛋白（Rec102、Rec104、Ski8、Rec114、Rec107和Mei4）也能促进冷点处的DSB形成，尽管频率不同。在测试的8种蛋白中，只有Mre11即使与GAL2处的UAS（GAL）结合也无法导致DSB形成。我们的结果表明，重组起始蛋白可能有几种方式相互关联形成一个能够产生DSB的功能性起始复合物。
