Sarno Roberta, Vicq Yoan, Uematsu Norio, Luka Marine, Lapierre Clement, Carroll Dana, Bastianelli Giacomo, Serero Alexandre, Nicolas Alain
Institut Curie, PSL Research University, CNRS UMR3244, Recombination and Genetic Instability, Paris F-75005, France.
Sorbonne Universités, UPMC Université Paris 06, CNRS UMR3244, Paris F-75005, France.
Nucleic Acids Res. 2017 Nov 2;45(19):e164. doi: 10.1093/nar/gkx739.
Meiotic recombination shapes the genetic diversity transmitted upon sexual reproduction. However, its non-random distribution along the chromosomes constrains the landscape of potential genetic combinations. For a variety of purposes, it is desirable to expand the natural repertoire by changing the distribution of crossovers in a wide range of eukaryotes. Toward this end, we report the local stimulation of meiotic recombination at a number of chromosomal sites by tethering the natural Spo11 protein to various DNA-binding modules: full-length DNA binding proteins, zinc fingers (ZFs), transcription activator-like effector (TALE) modules, and the CRISPR-Cas9 system. In the yeast Saccharomyces cerevisiae, each strategy is able to stimulate crossover frequencies in naturally recombination-cold regions. The binding and cleavage efficiency of the targeting Spo11 fusions (TSF) are variable, being dependent on the chromosomal regions and potential competition with endogenous factors. TSF-mediated genome interrogation distinguishes naturally recombination-cold regions that are flexible and can be warmed-up (gene promoters and coding sequences), from those that remain refractory (gene terminators and centromeres). These results describe new generic experimental strategies to increase the genetic diversity of gametes, which should prove useful in plant breeding and other applications.
减数分裂重组塑造了有性生殖过程中传递的遗传多样性。然而，其在染色体上的非随机分布限制了潜在遗传组合的格局。出于各种目的，通过改变广泛真核生物中交叉的分布来扩展自然库是很有必要的。为此，我们报告了通过将天然Spo11蛋白与各种DNA结合模块连接，在多个染色体位点局部刺激减数分裂重组：全长DNA结合蛋白、锌指（ZFs）、转录激活样效应因子（TALE）模块和CRISPR-Cas9系统。在酿酒酵母中，每种策略都能够刺激自然重组冷区的交叉频率。靶向Spo11融合蛋白（TSF）的结合和切割效率各不相同，这取决于染色体区域以及与内源性因子的潜在竞争。TSF介导的基因组检测区分了灵活且可以被“加热”的自然重组冷区（基因启动子和编码序列）和那些仍然顽固的区域（基因终止子和着丝粒）。这些结果描述了增加配子遗传多样性的新通用实验策略，这在植物育种和其他应用中应该会很有用。
