Genetic recombination arises during meiosis through the repair of DNA double-strand breaks (DSBs) that are created by Spo11, a topoisomerase-like protein^1,2. Spo11 DSBs form preferentially in nucleosome-depleted regions termed hotspots^3,4, yet how Spo11 engages with its DNA substrate to catalyse DNA cleavage is poorly understood. Although most recombination events are initiated by a single Spo11 cut, here we show in Saccharomyces cerevisiae that hyperlocalized, concerted Spo11 DSBs separated by 33 to more than 100 base pairs also form, which we term ‘double cuts’. Notably, the lengths of double cuts vary with a periodicity of 10.5 base pairs, which is conserved in yeast and mice. This finding suggests a model in which the orientation of adjacent Spo11 molecules is fixed relative to the DNA helix—a proposal supported by the in vitro DNA-binding properties of the Spo11 core complex. Deep sequencing of meiotic progeny identifies recombination scars that are consistent with repair initiated from gaps generated by adjacent Spo11 DSBs. Collectively, these results revise our present understanding of the mechanics of Spo11-DSB formation and expand on the original concepts of gap repair during meiosis to include DNA gaps that are generated by Spo11 itself.

减数分裂过程中，通过修复由 Spo11（一种拓扑异构酶样蛋白^{1,2 ）}产生的 DNA 双链断裂 (DSB)，发生基因重组。 Spo11 DSB 优先在被称为热点的核小体耗尽区域形成^3,4 ，但 Spo11 如何与其 DNA 底物结合以催化 DNA 裂解尚不清楚。尽管大多数重组事件是由单次 Spo11 切割引发的，但在这里我们在酿酒酵母中发现，也形成了由 33 到 100 多个碱基对分隔的超定位、一致的 Spo11 DSB，我们将其称为“双切割”。值得注意的是，双切割的长度以 10.5 个碱基对的周期变化，这在酵母和小鼠中是保守的。这一发现提出了一种模型，其中相邻 Spo11 分子的方向相对于 DNA 螺旋是固定的——这一提议得到了 Spo11 核心复合物的体外 DNA 结合特性的支持。减数分裂后代的深度测序识别出重组疤痕，这与相邻 Spo11 DSB 产生的间隙启动的修复一致。总的来说，这些结果修正了我们目前对 Spo11-DSB 形成机制的理解，并扩展了减数分裂过程中间隙修复的原始概念，将 Spo11 本身产生的 DNA 间隙包括在内。