RAD52 prevents accumulation of Polα-dependent replication gaps at perturbed replication forks in human cells.
RAD52 prevents accumulation of Polα-dependent replication gaps at perturbed replication forks in human cells.
复制标题
RAD52 可防止人类细胞中受干扰的复制叉处 Polα 依赖性复制间隙的积累。
DOI：
10.1101/2023.04.12.536536
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发表时间：
2023
期刊：
影响因子：
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通讯作者：
Pichierri,Pietro
中科院分区：
文献类型：
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作者：
DiBiagi,Ludovica;Malacaria,Eva;Aiello,FrancescaAntonella;Valenzisi,Pasquale;Marozzi,Giorgia;Franchitto,Annapaola;Pichierri,Pietro
复制间隙可能是 DNA 复制受到干扰的结果，它们的积累可能会破坏基因组的稳定性。 RAD52（一种参与叉逆转调节的蛋白质）的缺失会促进复制扰动期间亲本 ssDNA 间隙的积累。在这里，我们证明这是由于 Polα 参与了受干扰的复制叉逆转后广泛降解的下游，并且不依赖于 PrimPol。在 RAD52 不存在的情况下，Polα 在亲本 ssDNA 上过度招募，并且这种招募依赖于叉逆转酶和 RAD51。值得注意的是，我们报告说，RAD52 抑制刺激了 Polα 和 RAD51 之间的相互作用，并且 Polα 依赖性间隙积累需要 RAD51 成核，表明它发生下游链入侵。总而言之，我们的数据表明，当 RAD52 功能被禁用时，RAD51-Polα 依赖性重新启动对于促进分叉重新启动和限制 DNA 损伤积累至关重要。
Replication gaps can arise as a consequence of perturbed DNA replication and their accumulation might undermine the stability of the genome. Loss of RAD52, a protein involved in the regulation of fork reversal, promotes accumulation of parental ssDNA gaps during replication perturbation. Here, we demonstrate that this is due to the engagement of Polα downstream of the extensive degradation of perturbed replication forks after their reversal, and is not dependent on PrimPol. Polα is hyper-recruited at parental ssDNA in the absence of RAD52, and this recruitment is dependent on fork reversal enzymes and RAD51. Of note, we report that the interaction between Polα and RAD51 is stimulated by RAD52 inhibition, and Polα-dependent gap accumulation requires nucleation of RAD51 suggesting that it occurs downstream strand invasion. Altogether, our data indicate that RAD51-Polα-dependent repriming is essential to promote fork restart and limit DNA damage accumulation when RAD52 function is disabled.