PCNA dependent cellular activities tolerate dramatic perturbations in PCNA client interactions.
PCNA dependent cellular activities tolerate dramatic perturbations in PCNA client interactions.
复制标题
PCNA依赖性细胞活性在PCNA客户端相互作用中耐受剧烈扰动。
DOI：
10.1016/j.dnarep.2016.12.003
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发表时间：
2017-02
期刊：
影响因子：
3.8
通讯作者：
Green CM
中科院分区：
文献类型：
--
作者：
Wilson RH;Biasutto AJ;Wang L;Fischer R;Baple EL;Crosby AH;Mancini EJ;Green CM
我们评估了导致PARD的突变（PCNAS 228 I）的细胞效应。受影响个体的细胞对T2 AA和T3敏感。PCNAS 228 I破坏PCNA与Cdt 1、DNMT 1、PolD 3和PolD 4之间的相互作用。p21的PIP盒保留与PCNAS 228 I的结合。PCNA依赖性降解和细胞周期仅被PCNAS 228 I微妙地改变。增殖细胞核抗原（PCNA）是DNA复制和修复的重要辅助因子，将多种蛋白质募集到其作用位点。我们研究了导致PCNA相关DNA修复障碍（PARD）的PCNAS 228 I突变的影响。PARD患者的细胞对PCNA抑制剂T3和T2 AA敏感，这表明S228 I突变对未受损细胞有影响。PCNA和PCNA相互作用蛋白（PIP）之间的结合分析表明，S228 I的变化显着削弱了大多数这些相互作用，包括Cdt 1，DNMT 1，PolD 3 p66和PolD 4p 12。相反，p21在很大程度上保留了结合PCNA 228 I的能力。这种性质是由p21 PIP盒序列本身赋予的，这对于PCNAS 228 I结合是必要的和充分的。PCNA的泛素化不受S228 I改变的影响，这间接改变了结构域间连接环的结构。尽管PARD突变在体外对PIP-降解决定子结合有显著影响，但在受影响个体的细胞中，p21和Cdt 1的稳定性仅有微小改变。总的来说，我们的数据表明，减少的亲和力的PCNAS 228 I的特定客户端导致微妙的细胞缺陷，在未受损的细胞，这可能有助于PARD的病因。
We assess the cellular effects of the mutation that causes PARD (PCNAS228I). Cells from affected individuals are sensitive to T2AA and T3. PCNAS228I impairs interactions between PCNA and Cdt1, DNMT1, PolD3 and PolD4. The PIP-box of p21 retains binding to PCNAS228I. PCNA-dependent degradation and the cell cycle are only subtly altered by PCNAS228I. Proliferating cell nuclear antigen (PCNA) is an essential cofactor for DNA replication and repair, recruiting multiple proteins to their sites of action. We examined the effects of the PCNAS228I mutation that causes PCNA-associated DNA repair disorder (PARD). Cells from individuals affected by PARD are sensitive to the PCNA inhibitors T3 and T2AA, showing that the S228I mutation has consequences for undamaged cells. Analysis of the binding between PCNA and PCNA-interacting proteins (PIPs) shows that the S228I change dramatically impairs the majority of these interactions, including that of Cdt1, DNMT1, PolD3p66 and PolD4p12. In contrast p21 largely retains the ability to bind PCNAS228I. This property is conferred by the p21 PIP box sequence itself, which is both necessary and sufficient for PCNAS228I binding. Ubiquitination of PCNA is unaffected by the S228I change, which indirectly alters the structure of the inter-domain connecting loop. Despite the dramatic in vitro effects of the PARD mutation on PIP-degron binding, there are only minor alterations to the stability of p21 and Cdt1 in cells from affected individuals. Overall our data suggests that reduced affinity of PCNAS228I for specific clients causes subtle cellular defects in undamaged cells which likely contribute to the etiology of PARD.